movement physiology

yogabook / movement physiology

This separate glossary explains many terms and facts about the way our musculoskeletal system works in principle and in the field of gravity. The scope of the topic is difficult to narrow down and is multidisciplinary. The lever law and mass inertia are just as much a part of this chapter as the sine function and the algorithm, an elementary discussion of the behavior of muscles in monoarticular, biarticular and polyarticular cases, the resulting partial tendency to active insufficiency or passive insufficiency, the force-length relationship (which is indeed a polygonal function) or basic principles of movement physiology such as tension belts and rein systems. Elementary principles of training theory must be explained as well as the types of muscle contraction and the types and phases of muscle failure. The multitude of terms and related disciplines may be an indication that an interdisciplinary approach is indispensable for a conscientious consideration of the asanas. We call this multidisciplinary field: movement physiology.

A _ B _ C _ D _ E _ F _ G _ H _ I _ J _ K _ L _ M _ N
O _ P _ q _ R _ S _ T _ U _ V _ W _ x _ y _ z



See the own page.

Abduction (leg / hip joint)

the lateral abduction of a leg (without rotation and movement forwards/backwards), i.e. a movement in the frontal plane. The degree of possible abduction is a function of the degree of external rotation: In zero degree rotation, as in standard anatomical position, abduction is limited to a good 20°. With each degree of exorotation of the leg in the hip joint, the abduction capability increases and reaches its maximum at 90° or even higher, whereby it is then mainly limited by the monoarticular and biarticular extensors of the hip joint. Unfortunately, this fact is not consistently taken into account in the anatomical literature. It is highly relevant for poses such as trikonasana and warrior 2 pose.

Abduction, dorsal (arm / shoulder joint)

increasing the dorsal angle of the arm to the trunk, i.e. in standard anatomical position, lifting the arm backwards and upwards, generally referred to as retroversion in the shoulder joint. Reversing this movement to standard anatomical position is called dorsal adduction.

Abduction, frontal (arm / shoulder joint)

The increase in the angle of the arm in front of the body in relation to the trunk as a movement of the humerus in the glenohumeral joint, i.e. in standard anatomical position the lifting of the arm in the sagittal plane forwards and upwards. Synonym: anteversion in the shoulder joint.

Abduction, lateral (arm / shoulder joint)

Movement in the glenohumeral joint in which the lateral angle (in the fontal plane) of the arm to the trunk is increased. In the internally rotated state, the arm can hardly be abducted laterally by more than 90° before a firm-elastic or hard-elastic movement limit restricts the abduction, but if it is turned out, the abduction even with slightly above-average flexibility is only restricted by a soft-elastic movement limit, and more than 180° is possible with good flexibility.

Abductors (leg / hip joint)

Term for the group of muscles whose function (not necessarily exclusively) is to abduct the leg, i.e. to spread it to the side. The abductors of the leg include the gluteus medius, gluteus minimus, gluteus maximus, tensor fasciae latae, piriformis and obturator internus muscles.

Achilles tendon

the robust tendon into which the triceps surae (soleus and gastrocnemius) opens in order to bring the dorsal calcaneus closer to the popliteal region during its concentric contraction, which is referred to as plantar flexion or extension of the ankle. The Achilles tendon receives most of its arterial supply proximally and distally. It is most vulnerable in the area between the proximal and dorsal supply. In the case of a dorsal heel spur, the attachment area of the Achilles tendon to the calcaneus calcifies and ossifies. In contrast, Haglund’s heel is a ganglion on the dorsal cranial calcaneus, which presses on the Achilles tendon in a space-occupying manner. Both can irritate the Achilles tendon and trigger bursitis (inflammation of the bursa). Triggers can be mechanical irritation (heel cap of a new shoe), sporting overload (overuse) or a shortening of the gastrocnemius.

Active insufficiency

State of complete contraction of a muscle, i.e. complete interlocking of actin and myosin filaments, which does not allow any further active concentric contraction and thus movement caused by this muscle itself in a joint which this muscle spans, although the covered joint or the spanned joints themselves are not yet in the end position (reaching a soft-elastic, firm-elastic or hard-elastic limit of movement), i.e. the joint can be moved further by another muscle or passively (from outside, externally).


Adduction means moving towards. In the yoga book, the term is not used for the shoulder joint without a further designation (lateral adduction, frontal adduction), but it is used for the hip joint for the medial movement of the leg (also beyond standard anatomical position), as well as for the small and large fingers and toes (hallux, pollex). The conceptual opposite, abduction, is used for the movement away from the midline of the body, midline of the hand or midline of the foot.

Adduction (leg / hip joint)

the movement of the leg from a laterally abducted position to the medial, back to standard anatomical position or its movement beyond standard anatomical position further to the contralateral, i.e. this is a movement in the frontal plane.

Adduction, dorsal (arm / shoulder joint)

the reduction of the angle of the back of the arm to the trunk as a movement of the humerus in the glenohumeral joint, i.e. a movement in the sagittal plane: the movement of the arm from a raised backwards and upwards position back to standard anatomical position. The common term is retroversion.

Adduction, frontal (arm / shoulder joint)

the reduction of the angle of the arm in front of the body in relation to the trunk as a movement of the humerus in the glenohumeral joint, i.e. the movement of the arm from the forward-upward raised state in direction of standard anatomical position.

Adduction, lateral (arm / shoulder joint)

Movement of the arm in the glenohumeral joint, in which the lateral angle (in the fontal plane) of the arm to the trunk is reduced towards standard anatomical position.

Adductors (leg / hip joint)

Term for the group of muscles whose function is (not necessarily exclusively) the adduction of the leg, i.e. bringing the leg in from the side. They mainly originate in the area of the lower and lower lateral pubic bone. All monoarticular adductor muscles attach to different areas of the inner thigh bone, only the monoarticular adductor magnus muscle has an additional origin on the ischium and the biarticular gracilis muscle attaches below the knee joint on the inner upper tibia (on the pes anserinus superficialis). In addition to the gracilis, the adductor muscles of the leg include the adductor brevis, adductor minimus, adductor magnus, adductor longus and pectineus muscles and – in the pelvitrochanteric group of muscles, also caled the dorsal hip musculature – the obturator externus and the quadratus femoris muscles, which originate at locations other than those described above and attach at the trochanter major of the femur. The adductor magnus muscle is the only one that also attaches to the ischium and therefore has a internally rotating and extending effect on the thigh. The adductor compartment of the thigh is divided into:

  1. superficial: M. pectineus, M. gracilis and M. adductor longus
  2. middle: M. adductor brevis
  3. deep: M. adductor magnus and M. adductor minimus


An aerobic metabolism is one in which the supply of energy from carbohydrates (glucose circulating in the blood and stored in muscles) and fats is covered exclusively by oxygen consumption. The opposite of aerobic is where the oxygen supply is not sufficient to cover the energy requirement. Aerobic performance can be sustained over longer periods of time than anaerobic.

Aerobic threshold

The aerobic threshold is the level of performance demand from which the lactate level in the blood rises from rest (approx. 1.2 mmol/l) to approx. 2 mmol/l. When the aerobic threshold is reached, the energy supply ist no longer purely base on oxygen consumption and therefore more lactate is produced than at rest, but this can be broken down in real time as long as the anaerobic threshold has not yet been reached. The aerobic threshold is highly dependent on the level of training and can be around 60% of the maximum heart rate for people with little endurance training or around 85% for trained people. Training above the aerobic threshold but below the anaerobic threshold improves the vascularization of the muscles as well as the fat metabolism.


literally the „actor“, the muscle that performs a movement. Opposing muscles, i.e. muscles that perform the opposite movement, are called antagonists.


An algorithm is a rule for solving a task or a class of tasks. It can refer to a mathematical problem, a technical operation such as installing an operating system or program on a computer, making an object with a machine, or an everyday operation such as tying shoelaces or an apron or a Windsor knot on a tie. The algorithm can be more or less general, but in any case it must consist of a finite number of well-defined steps and should deliver the desired correct result in the usual application cases (termination). Typical algorithms used in practice are both determined (always deliver the same result with the same starting values) and deterministic (always deliver the result in the same, predictable way). There is more than one correct algorithm for many problems. Even if all correct algorithms lead to the same goal, they can do so with different resources (e.g. time or main memory). Getting by with few resources is called efficiency.

Ideally, taking a yoga pose is also described by an algorithm. This does not have to be linear but can contain conditions and branches, such as „IF the contralateral hand does not reach the floor, THEN use a block“ in the example of parivrtta trikonasana. In programming languages, conditional commands of the type IF CONDITION THEN STATEMENT1 (ELSE STATEMENT2) can be found in abundance, whereby an optional substitute statement STATEMENT2 can be specified, which is executed if the condition CONDITION is not fulfilled. In the case of parivrtta trikonasana, for example, the condition could also query whether there are any blocks left and specify support on the lower leg as a substitute instruction. The instruction „use a block“ can in turn represent a control loop of the type „repeat the increase in support by adding a block to the existing blocks until the fingers reach the block“. Such instructions are realized by control structures of the type REPEAT STATEMENT UNTIL CONDITION or WHILE CONDITION DO STATEMENT. Experienced teachers usually have these algorithms in their heads, even if they would not necessarily regard them as such or be able to write them down in every detail. In special cases that involve conditions that are not covered by his algorithm, he needs creativity and has to invent something new. This then enhances his algorithm. Algorithms can be represented in a flow chart, which graphically depicts the conditions, instructions and structures. In the case of asanas, the starting pose would be at the beginning, for example tadasana, and the target pose at the end.

Allochthonous back muscles

all back muscles that are not autochthonous. The allochthonous muscles are migrated limb muscles and are not primarily ones that move the spine but the limbs.


Anaerobic metabolism is a metabolism in which the energy supply is not exclusively covered by oxygen consumption but also partly without oxygen consumption, so that lactate is produced in larger quantities. In principle, a small amount of lactate is also produced at rest (up to approx. 1.2 mmol/l), but this can be disposed of without any problems, even far beyond the aerobic threshold of approx. 2 mmol/l lactate can be disposed of in realtime. The point at which this is no longer possible, but lactate accumulates in the blood, muscles and interstitium, is called the anaerobic threshold. It is around 4 mmol/l. Performance above the anaerobic threshold cannot be sustained over a longer period of time. In contrast to glucose, fats cannot be metabolized without an oxygen supply.

Anaerobic threshold

The degree of exertion or performance demand above which the body can no longer supply the muscles with sufficient oxygen, so that more lactate is formed during metabolism than can be broken down. Exceeding the anaerobic threshold leads to an increase in the concentration of lactate in the muscle, blood and interstitium. The lactate concentration is typically determined invasively by means of a blood test (capillary earlobe blood). The anaerobic threshold is approx. 4 mmol/l for most people, but can vary between 2.3 and 6.8 mmol/l depending on the individual. Lactate is also formed without physical exertion up to a concentration of approx. 1.2 mmol/l, increasing with the intensity of physical exertion. In addition to the anaerobic threshold, there is also the (now not uncontroversial) aerobic threshold, which is defined by the fact that the lactate concentration in the blood rises for the first time (with regard to increasing exercise intensity) compared to the resting concentration. For most people, this is around 2 mmol/l.

Endurance performance cannot be sustained above the anaerobic threshold for long periods of time. The anaerobic threshold can be exceeded for a short time (attack in a cycling race, sprint in soccer, etc.) without a drop in performance. It is closely related to a certain heart rate, speed (running, cycling) and power output. There is also a correlation with oxygen uptake: in untrained people, the lactate curve rises approximately parabolically from around 50% of maximum oxygen uptake; in top endurance athletes, this threshold is around 90%. The anaerobic threshold can be recognized simply and non-invasively in ergometry at approximately the point at which the heart rate, which previously rose linearly with the performance requirement, begins to rise non-linearly.

Irrespective of the anaerobic threshold at which continuous endurance performance can still be achieved, the glycogen reserves are exhausted after around 60 – 90 minutes (depending on the level of training), so that performance collapses even without the anaerobic threshold being exceeded. Appropriate food intake during performance cannot usually fully compensate for this effect.


Complete stiffening of a joint. This is usually caused by ossification of the joint space or increasing stiffening of the joint capsule, usually due to scarring.


Muscular opponent that performs a movement that is at least partially opposite to the muscle under consideration (agonist).


denotes a direction and means „in front of or towards the front“ and is identical to the term frontal or ventral. The conceptual opposite is posterior, which in turn corresponds to the term dorsal.

Anteversion (arm / shoulder joint)

Synonym: frontal abduction, lifting the arm forward.


flat connective tissue structure that serves as a muscle insertion, including the palmar aponeurosis, the plantar aponeurosis, the retinaculum patellae or the rectus sheath.


Bony attachments of tendons and ligaments with their own ossification center, which usually fuses with the main core of the epiphysis. Occasionally, however, it also remains independent. The apophyses at the muscle insertions of the rectus femoris, the adductors and the hamstrings are sometimes affected by damage. This ranges from minor changes to bony avulsion of the tendons. Depending on the muscles affected, pain often radiates towards the groin or buttocks. These disorders are easy to find radiologically, but their appearance is not uniform. Osteolytic processes and tumors must be clarified in the differential diagnosis

Arch of the foot

– Longitudinal arch of the foot

The concave cavity of the foot seen from the plantar side in the longitudinal direction of the foot. In addition to the passive bracing (tension belt) consisting of the plantar long ligament, the plantar calcaneonavicular ligament and the plantar fascia, which act as a tension belt to prevent the longitudinal arch from collapsing, several muscles are also involved in maintaining this as active bracing: In the lower leg, the deep flexors:

  1. Flexor hallucis longus
  2. Flexor digitorum longus

In the foot:

  1. Abductor hallucis
  2. Flexor hallucis brevis
  3. Flexor digitorum brevis
  4. Quadratus plantae
  5. Abductor digiti minimi pedis

In addition to the pronounced medial longitudinal arch, there is a very slightly pronounced, relatively rigid lateral longitudinal arch, which is supported by the muscles

  1. Flexor digiti minimi
  2. Opponens digiti minimi
  3. Abductor digiti minimi

When walking and running, the longitudinal arch flattens (the foot extends) in the standing leg in order to rebuild itself during and after pushing off through the use of the plantar foot muscles. A reduction or collapse of the longitudinal arch results in a flat foot. See also the overview map of the dorsal foot muscles.

– Transverse arch of the foot

The concave cavity of the midfoot and forefoot seen from the plantar side in the transverse direction of the foot. The passive tension consists of the transverse metatarsal ligament and the plantar cuboideonavicular ligament as well as the plantar aponeurosis, the active tension consists of the lower leg muscles

  1. Posterior tibialis
  2. Fibularis longus

and among the intrinsic foot muscles, especially the:

  1. Caput transversum of the Adductor hallucis

A reduction or collapse of the transverse arch can be seen in a splayfoot, which is usually easily recognized by the formation of calluses in the area of the metatarsophalangeal joints 2-3. See also the overview map of the dorsal foot muscles.

Arm flexors

All muscles that perform or support flexion in the elbow joint. These are primarily the biceps, brachialis and brachioradialis. Of the muscles that attach to the medial humeral epicondyle, only the palmaris longus is still considered a weak flexor of the elbow joint. The other muscles that attach there, such as the superficial and profound finger flexors, flexor carpi radialis and flexor carpi ulnaris, are not considered as such, although they cover the elbow joint. The muscles attached to the lateral epicondyle of the humerus also do not support flexion.

Arm stretchers

all muscles that perform or support an extension in the elbow joint. The only muscle to which this applies is the triceps. The anconeus, which is also located on the dorsal side of the elbow joint, is so weakly effective as an extensor that most authors only consider it to tense the joint capsule.


Arthrodesis usually refers to the irreversible surgical stiffening of joints in the sense of permanent invasive stiffening using an inflexible technical material. This is used, for example, after destruction of the joint due to trauma, severe infections, rheumatoid arthritis or osteoarthritis (arthrosis). In the latter case, the permanent pain of activated osteoarthritis is relieved and the instability eliminated. However, arthrodesis may also be indicated for other conditions, for example if a joint has become unacceptably unstable and no other treatment option is available. Arthrodesis may also be necessary if an artificial joint (endoprosthesis) has become unstable and cannot be replaced.

Where an endoprosthesis is available that technically largely reproduces the joint function, this option is generally preferred. While TEP is commonly used for the hip and knee joints, (permanent) arthrodeses are used for the hand and wrist, the joints of the foot and the spine if indicated. The cartilage of the joint surfaces is removed and, if necessary, autologous bone substance (e.g. from the iliac crest spongiosa) is inserted to improve the result. Nails, screws and plates are available for fixation. Temporary arthrodeses are usually K-wires (Kirschner wires). In the area of the spine, arthrodeses are called spondylodeses. Arthrodeses cause a change in movement patterns and shift the motion to neighboring joints, which are exposed to additional stress as a result. Depending on the stiffened joint, the loss of joint function can be compensated for to a greater or lesser extent.

Aseptic bone necrosis

ischemic bone necrosis (caused by a lack of supply), as occurs in the following diseases:

  1. Scheuermann’s disease: top and bottom plates of the vertebrae
  2. Perthes‘ disease: head and neck of the femur
  3. Osgood-Schlatter disease: tibial tuberosity
  4. Osteochondrosis dissecans: Femoral condyles (articular mice/articular calculus)
  5. Kienböck’s disease: Os lunatum (hand)
  6. Köhler’s disease I: Os naviculare (foot)
  7. Morbus (Freiberg-)Köhler II: Heads of the metatarsal bones


Physiological (e.g. by ageing or involutional atrophy: degeneration of organs that are no longer required, such as the thymus) or pathological reduction in the number (hypoplasia) or size (hypotrophy) of cells, which is associated with a loss of efficiency of the cell structure, furthermore with increased susceptibility and premature wear. There can be many different forms depending on the causes:

  • Pressure atrophy: prolonged exposure to pressure
  • Inactivity atrophy: prolonged non-use or immobilization
  • Trophic and nervous atrophy: supply problems or lack of nerve impulses
  • Endocrine atrophy: hormonal causes that lead to atrophy
  • Skin atrophy: various causes
  • Malnutrition (marasmus), emaciation (cachexia) in consumptive diseases such as tumors, TB


One of the methods of physical examination: listening. In connection with asanas, there is no auscultation in the strict sense, but acoustic perception does have a place, for example when the teacher perceives the presence of breathing, its intensity, its even flow or deviations from it and hears whether throat obstructions or constrictions occur. The cracking/crunching of joints, such as the knee joint, also provides information about the condition of the joints. Tendons can also make rubbing noises, also with a palpatory equivalent, which usually indicates tendovaginitis. When subluxations occur or a subluxation is repositioned, both perceptible phenomena regularly take place, palpatory which can be described as jumping, and acoustic phenomena, which correspond to them. In the case of noises emanating from joints, palpation can often give an idea of whether and which disorder is present, and whether medical clarification is required. The acoustic perception is also decisive in the impression of how smoothly a jump to the feet is achieved.

Autochthonous back muscles

the evolutionarily oldest and only „original“ back muscles that covers all dimensions of movement (but not directions: flexion is missing) of the spine (extension, rotation, lateral flexion). It is present in a very similar form in many mammals and vertebrates and is innervated by the dorsal rami of the spinal nerves. In contrast, all other dorsal muscles are innervated muscles of the extremities and are innervated by the ventral rami of the spinal nerves. The Mm. levatores costarum can be counted as autochthonous back muscles as they are also supplied by the rames dorsales of the spinal nerves, but one can also take a different view as they are also supplied by the rames ventrales.

The autochthonous back muscles can be divided into a lateral tract (also: superficial tract) and a medial tract (also: profound tract). The lateral tract consists of:

  1. Intertransversal system: Intertransversarii mediales lumborum (mediales and laterales), thoracis, cervicis (anteriores and posteriores). Innervated on one side: lateral flexion; bilateral: extension
  2. Spinotransversal system: splenius cervicis and capitis.
    Unilateral innervation: rotation of the head/spine; bilateral: lateral flexion
  3. Sacrospinal system: longissimus thoracis, cervicis, capitis and iliocostales lumborum, thoracis, cervicis.
    Innervated on one side: lateral flexion; bilateral: extension
  4. Rib lifting muscles: levatores costarum (breves et longes): Innervated on one side: lateral flexion; on both sides: extension

The medial tract of:

  1. Interspinal system: interspinalis (lumborum, thoracis, cervicis), spinalis (thoracis, cervicis, capitis)
  2. Transversospinal system: rotatores breves et longi (lumborum, thoracis et cervicis), multifidi (lumbales, thoracici, cervicis), Semispinalis (thoracis, cervicis, capitis)

There are also the suboccipital muscles („short“ or „deep“ neck muscles):

  1. M. rectus capitis posterior major
  2. M. rectus capitis posterior minor
  3. M. obliquus capitis inferior
  4. M. obliquus capitis superior

The rectus capitis lateralis and rectus capitis anterior muscles are not autochthonous. The part of the autochthonous back muscles that rotate and simultaneously extend the spine is sometimes referred to as the oblique system; these are the transversospinal system and the sacrospinal system. The oblique system is particularly relevant, firstly because it supports other rotatory muscles of the trunk such as the oblique abdominal muscles during rotation and thus prevents the oblique abdominal muscles from having to work excessively and possibly developing excessive tone, which could make inhalation more difficult since it flexes the trunk, and secondly because many more or less pronounced combinations of flexion of the spine and rotation can be found in everyday life, starting with tying shoelaces, for example.


Bony avulsion of a tendon, i.e. under load the tendon tears out a piece of bone at the insertion site. This occurs in particular when the bone structure is damaged, but sometimes also due to extreme (usually eccentric) load without pre-existing damage to the bone.

Avulsion fracture

Synonym for avulsion.

Axial misalignment

Axial misalignment is a deviation from the norm, usually of the extremities. The most common and best known are axial malalignments of the knee joint in the frontal plane: knock knees and bow legs. In addition, malalignments occur in the sagittal plane as genu recurvatum (extremely hyperextensible knee joint) and very rarely as genu procurvatum (extension deficit, for example due to arthrofibrosis, cyclops after cruciate ligament plastic surgery, meniscus entrapment) as well as in the transverse plane as internal and external torsion. Physiologically, the hip joint, the knee joint and the ankle joint lie on the same line, the Mikulicz line, the weight-bearing line of the lower limb. Physiologically, the knee joint has an external angle of 173° – 175°, which is caused by the angle in the femur (the CCD angle between shaft and neck). A deviation of the lower leg from its expected and physiological course towards the medial side, i.e. a varus position, is referred to as bow leg or genu varum. If the lower leg deviates outwards, i.e. there is a valgus position, this is known as a knock-knee or genu valgum. In the lower extremity in particular, axial misalignments usually lead to damage to the musculoskeletal system over time, not least depending on the intensity of use. Similar axial misalignments are occasionally found in the upper extremity, but with a few exceptions these often remain asymptomatic for longer due to the much less heavy use compared to the lower extremity (standing, walking, running). In the elbow joint, a small valgus position is physiological; up to 10° is considered physiological in men and up to 15° in women. Angles beyond this are considered cubitus valgus. Cubitus valgus and its varus counterpart cubitus varus usually have a traumatic background or result from a chronic tendency to dislocate. In asanas, care must be taken to ensure that the misalignments do not become more pronounced. Depending on the construction of the pose, the effect of gravity tends to further express an existing valgus or varus position, as the line of support does not run in a straight line through the joint, but results in a valgus or varus torque from the existing malposition. This can impair the ligament and cartilage structure and thus cause joint instability and arthrosis (osteoarthritis). As in the case of the knee joint, a realignment osteotomy would be considered after completion of longitudinal growth in the case of pronounced malalignment. If the function of the joint is impaired or nerves are affected, the decision may have to be made earlier. When performing asanas, an appropriate force must be built up in the respective joints of the trunk (shoulder joint or hip joint) in such a way that it neutralizes the damaging torque as well as possible. For example, if there is a clear valgus position of the elbow joint in purvottanasana with the hands pointing backwards, a force in the direction of lateral abduction must be built up in the shoulder joint; in the case of a varus position lateral adduction, of course. The same applies to the upface dog and downface dog. In general, when feet oder hands are punctum fixum, the force must be exerted in the opposite direction in which the limb mid joint (elbow joint, knee joint) deviates from the expected line, that is in the direction in which the limb end joint (wrist or ankle) deviates from the expected path. With the foot or hand as a punctum fixum a relieving moment in the limb mid joint is created. The rotational situation of the limb in the pose must be carefully observed. In the downface dog and all other overhead poses of the arms, external rotation is less possible, which slightly changes the direction in which pressure would ideally be applied.


Ball joint

see under joint shapes

Bankart lesion

Partial or complete avulsion of the lower glenoid labrum in the shoulder joint due to anterior dislocation of the shoulder joint. The Bankart lesion is a cause of recurrent dislocations. If the labrum alone is torn off, it is referred to as a soft lesion; if the bone is also affected, as in the case of an avulsion, it is referred to as a hard lesion.


Two-jointedness of a muscle, i.e. the property of a muscle to span exactly two joints and cause a movement in these. The movement can be the same in both joints (flexion or extension) as e.g. in finger joints or the spine, or flexion in one joint and extension in the neighboring joint (example: rectus femoris muscle). In addition to biarticular muscles, there are also monoarticular (covering one joint) and polyarticular (covering more than two joints) muscles.

Biceps anchor

The origin of the tendon of the long head of the biceps at the superior cartilage lip of the glenoid is referred to as the biceps anchor. The origin on a cartilage is naturally less resilient than a bony origin. Extraordinary tensile stress in particular can therefore cause this area of the cartilage to tear, which is referred to as a SLAP lesion.
There are already three variants for the superior labrum; the anchoring of the tendon to it shows another four types, depending on how the fibres are distributed between the anterior and posterior labrum

Body mass

Body mass refers to the physical mass of the body. In application, however, the weight of this mass in the Earth’s gravitational field is usually more relevant. Various authors have given slightly different values for the parts of the body based on different samples, here are just a few examples.

Men / Women
Head6,72 / 8,127,068,1
Trunk46,30 / 43,9042,7049,7
Upper arm2,65 / 2,603,362,8
Forearm1,82 / 1,822,281,6
Hand0,70 / 0,550,840,6
Thigh12,21 / 12,8911,589,9
Lower leg4,65 / 4,345,274,0
Foot1,46 / 1,291,791,4

The centers of gravity of the partial body weights of these body parts lie relatively exactly on the lines connecting the joint rotation centers. In the case of the extremities, they can be specified as proximal proportions of the total distance between the rotation centers of the joints as follows:
upper arm: 47%,
forearm 42%,
thigh 44%,
lower leg 42%,
foot 44%.
This reflects the fact that the limbs of the extremities narrow distally. The center of gravity of the head is approximately midway between the auditory canals, that of the torso at about 44% of its length cranially.

Brachial plexus

As part of the PNS, the brachial plexus is a nerve plexus consisting of the ventral branches of the spinal nerves of the last four cervical spine segments and the first thoracic spine segment (C5-Th1) as well as smaller bundles of C4 and Th2. Compression of the brachial plexus can lead to thoracic outlet syndrome.


reduced heart rate. Bradycardia is present in a few diseases, and also physiologically in endurance athletes. Strictly speaking, a heart rate below 60 bpm is a bradycardia, but the resting heart rate of well-trained endurance athletes is often well below 50 beats, in some cases even below 40. The Spanish professional cyclist Miguel Indurain had the lowest resting heart rate ever measured in a healthy person at 28 bpm. See also tachycardia.


Bradypnoea refers to a reduced breathing rate at rest, in adults less than 8 breaths per minute. In the physiological case, the respiratory rate depends on the oxygen demand of the tissues, i.e. it is increased during physical activity. At rest, it is usually between 12 and 16 breaths per minute, in newborns between 30 and 50, in premature babies up to 80. During meditation and relaxation procedures, it can fall well below 12, but also in some pathological cases. A breathing rate that is too fast is called tachypnoea.


Bradytrophic means slow-metabolizing. This describes a property of tissues and reflects their metabolic rate and their turn over. Tissues with a slow metabolism often take more than a year to completely regenerate; in the case of cartilage, this can no longer take place at all due to the very slow metabolism. As a result, they heal very slowly after injury and regenerate very slowly after stress. Many of the bradytrophic tissues are not supplied by arteries and are therefore not permeated with capillaries, but are only supplied by diffusion through changing pressure in movement. This applies to cartilage and parts of the bones, for example. However, there are also mixed forms, such as the meniscus of the knee, which is capillarized on the outside and not on the inside. With their slow metabolism, slow healing and slow regeneration, they are preferentially affected by overuse syndromes. The conceptual opposite of bradytrophic is tachytrophic.


The bursae are fluid-filled cushions, usually in the course of muscles or tendons, to keep local pressure peaks away from them. For example, the iliopectineal bursa buffers the course of the iliopsoas tendon via the eminentia iliopubica. When the hip joint is extended, the line connecting attachment and origin of the iliopsoas lies behind the eminentia iliopubica, so that there must be significant pressure on the tendon. Without a bursa, the tendon would quickly become irritated and degenerate.
Bursae can be connected to a regional joint and are then described as communicating with it. Bursae can also communicate with each other.
A distinction is also made between bursae that are present at birth (constant) and bursae that have developed as a result of triggers (inconstant).

– Structure of the bursa

Bursae consist of two layers:

  • Membrana fibrosa (outer layer, also known as stratum fibrosum): consists mainly of collagen fibers
  • Membrana synovialis (inner layer): produces and, if necessary, reabsorbs synovial fluid and thus enables smooth, pain-free movement.

– Classification according to buffer function

  • Bursa subcutanea, especially where skin lies directly on bone
  • Tendon bursa (bursa subtendinea) between tendons and bone
  • Intervertebral bursa (subligamentousbursa) between ligaments and bone
  • Muscle bursa (submuscularbursa) between muscles and tendons or bones
  • Fascial bursa (subfascialbursa) between a fascia and the underlying bone

– Classification according to occurrence

  • constant / congenital: occurring in the same place in all people
  • inconstant / reactive: acquired. Skin bursae are always reactive.

An overview of many burses in the human body can be found here.


Capsule (joint capsule)

Part of the passive musculoskeletal system that forms the outer boundary of a joint and encloses the articulating bone ends.
With its innermost layer, the synovia (synovial membrane), the joint capsule forms the synovial fluid of the same name, a fluid with a high hyaluronic acid content whose viscosity changes adversely with decreasing temperature.
The outer layer (membrana fibrosa) consists of staffy collagenous tissue and is connected to the periosteum of the bone. The joint capsule contains Ruffini corpuscles, Vater-Pacini corpuscles and Golgi tendon organs, which serve as sensors for proprioception. Free nerve endings serve as nociceptors for pain perception. Some joint capsules are reinforced in strips to form capsular ligaments (ligamenta capsularia). In addition to the limitation of movement by the capsule, there may be other ligaments both outside (extracapsular) and inside (intracapsular) the joint capsule. If more than two bones are involved in a joint, as in the case of the wrist, knee or ankle joint, the synovial membrane can delimit individual spaces. Capsules can be damaged by trauma and may not guide the bones sufficiently in the long term, resulting in joint instability. In these cases, there is often also a torn muscle fiber or torn ligament. If the capsule tears as a result of trauma, this can lead to hemarthrosis (bleeding into the capsule). Inflammatory processes can lead to swelling of the ligaments and loss of flexibility. The synovial membrane often reacts to injuries to the capsule by producing more synovial fluid.

Capsular ligament

A capsular ligament is usually a strip-shaped fibrous reinforcement of a joint capsule, i.e. a part of the joint capsule designed as a ligament.

Capsulitis (capsulitis)

An inflammatory change in the joint capsule that can potentially occur in various joints, associated in particular with pronounced pain and restricted flexibility. The most common is capsulitis adhaesiva of the shoulder joint (periarthropathia humeroscapularis). The hip joint is the second most commonly affected after the shoulder joint.

Carpal tunnel

Palmar depression in the carpus (entirety of the carpal bones) through which the median nerve, the tendons of the profund finger flexors (flexor digitorum profundus muscle), superficial finger flexors (flexor digitorum superficialis muscle) and the long thumb flexor (flexor pollicis longus muscle) run. Some authors also include the flexor carpi radialis muscle. The carpal tunnel is covered by a retaining ligament (retinaculum), the flexor retinaculum. Swelling of the tendons can lead to pressure on the nerve and thus to carpal tunnel syndrome, a nerve compression syndrome.


The entirety of the carpal bones, see under bones of the hand.


Cartilage is part of the passive musculoskeletal system. It is usually not vascularized and is supplied by diffusion when pressure changes during movement. It serves as a pressure-elastic and bending-elastic buffer. As such, it forms the coverings of articulating bone areas. Physiologically, these are made of hyaline cartilage; if this is permanently damaged in the course of osteoarthritis, it can be replaced by fibrous cartilage.

Cauda equina

from Latin: caeuda equina, horse’s tail, refers to the nerve roots of the spinal nerves that continue caudally towards the sacrum after the end (conus medullaris, approximately level L1) of the spinal cord and leave the spinal column through their corresponding intervertebral foramina.


refers to a position close or (in comparison) closer to the lower end of the trunk. The conceptual opposite is cranial.

Center of gravity

The center of gravity of a (usually 3-dimensional) body is the mass-weighted average of the positions of its mass points and is therefore also simply referred to as the „center of mass“; a more correct term would be „mass-weighted average“. This means that the center of mass does not necessarily have to be in the body; counterexamples are a boomerang or a person standing in downface dog of in the back arch.

Cervical spine (cervical spine)

The part of the spine consisting of 7 vertebrae above the thoracic spine and below the occiput (occipital bone). The uppermost vertebrae C1 (atlas) and C2 (axis) have a special shape to allow maximum rotation.


Circumduction (pathological or unphysiological) refers to a circular movement of the leg in the hip joint when the hip flexors, the muscles that can move it forward in a straight line, fail, are insufficient or are too weak to meet the requirements. In the Wernike-Mann gait pattern, this can be seen as a consequence of apoplexy, for example, but multiple sclerosis can also lead to this.


In principle, chondrosis refers to any cartilage degeneration, but the term is usually used as chondrosis intervertebralis in relation to the intervertebral discs. With increasing age, the intervertebral discs change adversely in several ways: the proteoglycan content of the nucleus pulposus decreases, which reduces the water-binding capacity (swelling capacity), and the collagen content increases, which makes the nucleus pulposus firmer and harder. In addition, defects develop in the annulus fibrosus, in which the fibrous tissue arranges itself into fibrils, which can allow the passage of material from the nucleus pulposus and cause a prolapse. Overall, the intervertebral disc loses height, which is consistent with the decrease in height with age, even without a change in the shape of the spinal column, for example due to hyperkyphosis of the thoracic spine. Chondrosis of the intervertebral discs puts a strain on the facet joints, so that sooner or later these will lead to osteoarthritis (arthrosis) called spondylarthrosis, which often results in facet syndrome. Furthermore, the risk of disc hernias (herniated and bulging discs) increases. In addition, the changes in the intervertebral disc affect the vertebral body, which tends to develop spondylosis, which can be seen radiographically as irregularly compacted top and bottom plates; spondylophytes (osteophytes of the vertebral body) are also common. Spondylosis is known to be a natural sign of ageing in many vertebrates.


Cold is physically a lower degree of molecular vibration. This is an aggravating factor for physiology. Muscles are less elastic in the cold, blood circulation in the body in general and in the muscles in particular is poorer because the capillaries contract in response to the cold so that less heat energy is lost to the outside world. The synovia becomes more viscous and joint lubrication deteriorates. As a result of these factors, performance decreases and the risk of injury increases significantly. Moisture is an important cofactor of cold due to increased thermoconductivity.

Collateral ligaments

Collateral ligaments are ligaments of joints that lie parallel to the extension of a part of an extremity and not on the flexor or extensor side, but medially or laterally. In the example of the knee joint, these are the medial and lateral collateral ligaments.

Collateral ligament (knee)

the inner and outer ligaments running longitudinally on the medial and lateral side of the knee joint, which tighten when the knee joint is extended and thus prevent internal rotation and external rotation of the lower leg in the knee joint. Another function of the collateral ligaments is to prevent varus movements and valgus movements by absorbing corresponding forces. See knee joint: Collateral ligaments.

Communicating / communicating

Connection between two spaces, to be physiologically connected. This term is used, for example, when two bursae are connected to each other or when a bursa is connected to the associated joint space, i.e. a connection exists between them that allows the exchange of synovia. If a communicating bursa is referred to without specifying a further anatomical structure, communication with the joint cavity is meant.


Property of an anatomical structure to be regularly developed in all people. Examples include bursae or ligaments, which all people develop, whereas others are not found regularly and are then called inconstant.

Concentric contraction

Muscle contraction in which actin and myosin in the sarcomeres interlock further, reducing the distance between the M- and Z-discs so that the distance between the origin and attachment of the muscle is reduced. In addition to concentric contraction, there is also eccentric, isometric and isotonic contraction. Concentric contraction is also known as miometric contraction (mio: gr.: short). Bei konzentrischer Kontraktion gegen einen gewissen Widerstand entwickelt ein Muskel weniger Kraft als bei exzentrische Kontraktion. This dependence is also speed-dependent, which was described by Hill in the equation of the same name, which states that the speed is in inverse proportion to the force.

Concentric muscle failure

the first form of muscle failure to occur: the inability to continue concentric contraction, for explanation and example see muscle failure.

Condyloid joint / ellipsoidal joint

see under joint shapes


A contraindication is a circumstance that prohibits the use of a remedy or procedure, here a pose, an exercise, the use of an aid, a transition or something else.


refers to a fixed misalignment that can no longer be brought into the physiological position as the conceptual opposite of reducible. Contractual malpositions cannot be corrected conservatively.


The contraction of a muscle or „muscle contraction“ is the process in which a muscle applies contraction force beyond its resting innervation and consumes more energy (compared to the resting state) in the form for hydrolysis of ATP to ADP. A chemical reaction of the protein myosin, which is attached to the middle disk (M-disc) of the sarcomere, causes a geometric change in its head, which docks onto variable sites of the protein actin, which is attached to the Z-disk bordering the sarcomere, leading to a shortening of the sarcomere. A distinction is made between concentric, eccentric, isometric and isotonic contraction. If nothing else is specified, contraction is generally understood to mean concentric contraction. For a more detailed description, see the structure of the sarcomere and the description of the contraction mechanism on Wikipedia.

Contractile force / Contractive force

The force with which a muscle contracts, i.e. pulls its attachment and origin towards each other. The easiest way to understand the contraction force is as the axial tensile load applied in one (some muscles of the musculoskeletal system do not attach to both ends with tendons, but possibly directly to bones) or both tendons, the tendon force.

Corrective osteotomy

also known as axial correction: surgical removal of a wedge-shaped piece of bone to correct an incorrect joint position. The corrective osteotomy is mainly used for the two large joints of the lower extremities, for the knee joint in the case of pronounced knock knees or bow legs or for the hip joint, for example in Perthes‘ disease. The aim of the osteotomy is to prevent serious damage that is to be expected as a result of the malalignment, such as arthrosis in the case of knee malalignment or necrosis of the femoral head in the case of Perthes disease.


refers to a position near or (in comparison) closer to the upper end of the trunk or head. The conceptual opposite is caudal.

craniocingular muscles

Muscles that run from the skull to the shoulder blade:


The term crepitations, usually used in the plural, refers to a palpatory or auscultatory „crackling“ or „rustling“, sometimes also referred to as „crackling rattle“. This also includes „snowball crunching“, which is typical of tendovaginitis. Other conditions with crepitations are fractures and advanced osteoarthritis, in which bones (instead of their cartilage surfaces) are rubbing against each other.

Cruciate ligament

the two ligaments that run extra-articularly but intracapsularly in the knee joint and prevent the tibia from shifting ventrally or dorsally in relation to the femur: anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). If they are damaged, unphysiological displacements occur, resulting in instability during movement and increased wear of the knee joint. Damage such as overstretching and tears can be recognized by the anterior or posterior drawer effect. For more information, see knee joint: cruciate ligaments.

Cubital tunnel

lateral depression in the elbow area, a few centimeters proximal and distal to the elbow joint, through which the ulnar nerve runs, which primarily supplies the 4th and 5th fingers. Therefore, prolonged pressure on the nerve or trauma can lead to cubital tunnel syndrome (sulcus ulnaris syndrome, ulnar groove syndrome), the second most common nerve compression syndrome in humans.

Cyclical movement

A cyclical movement is a sequence of movements whose end is identical to the beginning, so that it can be performed as often as desired in succession. Examples include all forms of walking, running, sprinting, but also the dips of the downface dog, of the handstand, of the staff pose, caturkonasana jumping or – in sporting disciplines – the bench press or rowing. Basically, most forms of locomotion that allow you to cover a greater distance belong to the cyclical movement patterns.


see the dedicated page on cycling.


Dead space / dead space volume

The dead space volume is the space between the nasal cavity, oral cavity, pharynx, trachea and bronchi in the respiratory system that is involved in the transport of respiratory air. It averages around 150 ml and must be subtracted from the respiratory effective tidal volume of around 500 ml, so that only around 350 ml contributes to gas exchange.

Depression (shoulder blade)

Downward movement of the shoulder blade (caudal, towards the pelvis). The scapula is (terminologically) „depressed“. The muscles performing the movement are the depressors of the scapula. The counter-movement is called elevation.

Depressors (shoulder blade)

Muscles that move the shoulder blade caudally, i.e. in the direction of the pelvis:

  1. Trapezius (pars ascendens, most important dorsal depressor)
  2. Latissimus dorsi (only indirectly)
  3. Serratus anterior (directly)
  4. Pectoralis minor (directly, most important ventral depressor)
  5. Pectoralis major (only indirectly)


A dermatome is the area of skin supplied by a spinal nerve.
See this illustration.


The area of a long bone between the growth plates. This is where the bone marrow is located.

Dimension of movement / movement dimension

The entire range of movement (ROM, formerly also called traffic space) of a joint can be represented with independent dimensions so that each position has unique coordinates. A movement therefore corresponds to a curve in this space. A certain standard coordinate system is common, whose axes are given by vectors on the directions: frontal, cranial, lateral (dexter), which correspond to normals on the frontal plane, transverse plane and sagittal plane. Typically, the ROM is a convex set.


Training form with cyclical movement in which flexion and extension of the elbow joint are used to strengthen the triceps using the body’s gravity. The position of the body in relation to the arms can vary. This makes dips the analogy to squats, as both strengthen the extensors of the middle joints of your limb.

Disc meniscus / Meniscus disciformis

Contrary to previous opinion and according to the latest research, this is not a congenital anomaly of the meniscus shape, but rather an anomaly acquired as a result of incorrect mechanical loading, in which the inner meniscus is rarely (5%), but usually (95%) the outer meniscus is not crescent-shaped, but rather disc-shaped, in 20% of cases also bilaterally. No disc meniscus has yet been detected in the embryonic stage. The disc meniscus often remains asymptomatic and undetected for a long time. The disc meniscus was described by Young as early as 1889. Depending on the literature, 0.4% to 17% of the population are affected, and in Asian countries, especially Japan, significantly more. Pinching of the meniscus between the tibia and femur can lead to a reproducible, usually painful snapping phenomenon, which does not usually occur before the 6th – 8th year of life. MRI can detect the disc meniscus. It tends to have central tears. Its fixation can vary greatly, which can lead to free flexibility, pressure on the joint capsule or locking of the joint with corresponding pain. Tears are an indication for arthroscopic removal and restoration of a physiological shape. If the meniscus proves to be insufficiently fixed, this must also be repaired. Complete removal of the meniscus, even of just the lateral or, rarely necessary in this context, the medial part, leads to a tens of times higher risk of arthrosis, which is why it must be avoided without the strictest indication.


refers to a position in a limb far or (comparatively) further away from its attachment to the trunk. The conceptual opposite is proximal.

Distinctive muscles

Identifier muscles are muscles that are tested as a proxy for a myotoma and a spinal nerve in clinical testing, for example if there is suspected damage to a segment of the spine.

Some of the characteristic muscles can be tested with very simple tests:

  1. Quadriceps: squat
  2. Triceps surae: toe stand
  3. Tibialis anterior: ball of foot stand


denotes a direction and means „on the back“, „behind“ or „to the rear“ and is identical to the term posterior, except that the latter is hardly used in limbs. The conceptual opposite is frontal, which in turn corresponds to the term anterior or ventral.

Dorsal flexion (foot)

Reduction of the dorsal (back of the foot) angle of the foot to the lower leg. This movement is carried out by a group of muscles that are also referred to as „dorsiflexors“. For the kinetics of walking, the foot dorsiflexors are of much less importance than the plantar flexors, which (depending on the walking style) can make a significant contribution to propulsion through extension (plantar flexion) in the ankle. In addition to the monoarticular soleus, this is primarily the gastrocnemius, which also flexes in the knee joint, giving it a favorable working range, as the knee joint is flexed and the ankle dorsiflexed when stepping forward, but the opposite occurs in both joints when pushing backwards: palmar flexion and extension in the knee joint. A comparable structure is completely absent in the dosriflexors, none of them covers the knee joint. This is also not necessary, as the force they can exert is far less, as they only have to prevent the toes from hitting the ground through dorsiflexion of the ankle when the foot is pulled forward for the next step, but as mentioned above, they do not have to contribute to propulsion.

Dorsal flexion (hand)

Reduction of the dorsal (back of the hand) angle of the hand to the forearm in the wrist.

Dorsal hip muscles / pelvitrochanteric muscles

see the separate page dorsal hip muscles

Dorsal flexors (foot)

These are generally referred to as dorsiflexors, see there.

Dorsiflexors (foot)

All muscles that perform dorsal flexion in the ankle (more precisely: the ankle joints, although this movement occurs almost exclusively in the ankle and only very subordinately in the Chopart and Lisfranc joint lines), i.e. reduce the dorsal (dorsalis pedis) angle of the foot to the lower leg or move the dorsum of the foot towards the lower leg. These are M. extensor hallucis longus, M. extensor digitorum longus, M. tibialis anterior.

Dorsiflexors (hand)

Muscle group that moves the back of the hand towards the forearm:


Disturbance of the physiological movement sequence: disruptive factors lead to non-physiological movement. In addition to the musculoskeletal system, this term is also used in other disciplines.


Difficulty swallowing.


Shortness of breath.


Misgrowth of tissue, but in contrast to atrophy due to genetic or traumatic causes or in the context of diseases such as Sudeck’s disease (CRPS 1) or Duchenne muscular dystrophy. As with atrophy, there is a reduction in the performance of the cell structure, increased susceptibility and premature wear and tear.


Eccentric contraction

Muscle contraction in which the interlocking of actin and myosin in the sarcomeres is reduced, i.e. the distance between the M- and Z-discs increases, so that the distance between the origin and attachment of the muscle increases. In addition to eccentric contraction, there is also concentric, isometric and isotonic contraction. The eccentric contraction is also known as the pliometric contraction (plio: gr.: long).

Eccentric muscle failure

the last form of muscle failure, occurring after the other two forms or stages: the inability to perform an eccentric contraction at a slow speed in a controlled manner. For an explanation and example, see muscle failure.

Elevation (shoulder blade)

Movement of the shoulder blade upwards (cranial), away from the pelvis. The executing muscles are the elevators of the scapula. The opposite movement is called depression. The elevation of the shoulder blade corresponds to its elevation when shrugging. The further the arms are abducted (laterally or frontally), the more the possible elevation depends on the flexibility of the latissimus dorsi and subordinate also the pectoralis major, for example, which – attached to the main trunk – are indirect depressors of the scapula. In an upright posture, elevation occurs against the force of gravity, so that it is automatically reset from its effect. Nevertheless, many people keep their shoulder blades partially elevated for endogenous reasons, which leads to tension in elevators such as the levator scapulae or the trapezius.

Elevators (shoulder blade)

Muscles that move the shoulder blade cranially, i.e. towards the head:

  1. Trapezius pars descendens
  2. Levator scapulae
  3. Rhomboideus major
  4. Rhomboideus minor
  5. Serratus anterior

Ellipsoidal joint / Condyloid joint

see under joint shapes


Endurance is the physical ability to perform prolonged exertion, i.e. the resistance to fatigue and the ability to regenerate quickly. Endurance is one of the basic components of fitness. This usually relates to sporting activities, but is not limited to these. In working life, too, endurance is sometimes required. At its simplest, endurance is the ability to perform more or less consistently over as long a period as possible. The slight vagueness of „more or less constant“ refers to the fact that, in practice, topographical conditions or wind modulate the performance requirement when running, for example. In addition to the absence of physical fatigue, mental endurance, i.e. the absence of mental fatigue, is also a not insignificant factor, whereby both factors influence each other. Endurance also includes recovering as quickly as possible after a performance.

Endurance sports

see the dedicated page on endurance sports


Energy is the quantified ability to cause something, be it in the form of work or radiation, i.e. also heat. Energy occurs in various forms that can basically be converted into one another, for example as potential, kinetic, electrical, chemical and thermal energy. When a person lifts an object, they „consume“ chemical energy and add potential energy to the object. If you accelerate your bicycle, you convert chemical energy into kinetic energy. A conventional filament bulb converts electrical energy into 95% heat radiation and 5% light radiation.

Epiphysis / Epiphysis ossis

The cartilaginous end of a long bone in which bone nuclei develop during growth, allowing the bone to grow. The epiphysis is separated from the diaphysis, in which the bone marrow is located, by the epiphyseal groove (growth plate). In relation to the center of the body, we speak of a proximal and a distal epiphysis. If the epiphysis is part of a joint (unlike the proximal epiphysis of the distal phalanges of the toes and fingers), it is covered with hyaline cartilage (articular cartilage) in the area of the articulation.

Epiphyseal joint / growth plate

The cartilaginous transition area from the epiphysis of a long bone to the metaphysis, in which bone nuclei develop during growth, allowing the bone to grow. At around 20 years of age, the longitudinal growth that starts at the epiphyseal joints is complete. At the same time, the STH level decreases and the epiphyseal joints ossify.

Eversion (foot)

Eversion, as the exact opposite movement to inversion, is the sum of movements in the lower ankle joints (posterior lower ankle joint/subtalar joint and Chopart joint line) and dorsiflexion in the upper ankle joint: eversion consists of pronation, dorsiflexion and abduction.

Examination methods / physical examination methods

Methods of physical examination include:


Exostosis is a bone proliferation of the compact bone, e.g. as a benign bone tumor or osteoma. It can be caused by irritation, for example by repeated local pressure, in which case it is also referred to as a bony ganglion.


Exhalation. Like inhalation, this has 2 possible parts: chest and abdominal breathing. During abdominal expiration, the diaphragm is relaxed so that it can return to its cranially extended resting position. Chest expiration takes place at a slow pace in an upright posture (upper body halfway vertical, head up) by gravity. It is slightly accelerated with the help of the expiratory respiratory muscles and forced with the help of the expiratory auxiliary respiratory muscles. In lung function diagnostics, the Tiffeneau test is used to check for obstructive restrictions in the airways that hinder expiration.

Expiratory auxiliary respiratory muscles

Muscles that can be used during powerful exhalation:

  1. M. obliquus externus abdominis
  2. M. obliquus internus abdominis
  3. M. transversus abdominis
  4. M. latissimus dorsi („cough muscle“)
  5. M. quadratus lumborum
  6. M. rectus abdominis

Expiratory respiratory muscles

Muscles that are used during normal exhalation:

  1. Mm. intercostales interni et intimi (internal intercostal muscles)
  2. M. subcostalis
  3. M. transversus thoracis

Expiratory reserve volume

the lung volume that can be additionally exhaled during forced expiration after normal, unstressed expiration.

Extension (elbow joint)

Extension in the elbow joint, i.e. increasing the (internal) angle between the upper arm and forearm to 180° and possibly beyond (hyperextension).

Extension (finger joint)

With the exception of the thumb, in addition to the metacarpophalangeal joint (MCP), there are 2 joints per finger, a proximal joint (closer to the wrist: proximal interphalangeal joint, PIP) and a distal joint (further away from the wrist: distal interphalangeal joint, DIP). In both, extension (stretching) in the sense of increasing the palmar (internal) angle is possible up to 180° and possibly beyond (hyperextension). Hyperextension of all finger joints is physiological to a small extent, somewhat more in the metacarpophalangeal joint than in PIP and DIP. However, if a metacarpophalangeal joint of a little finger can be hyperextended by at least 90°, a point is awarded in the Bighton score for hypermobility.

Extension (cervical spine)

Tilting the head backwards towards the back, i.e. „craning the neck“. The extension of the cervical spine is also often referred to as reclination.

Extension (hip joint)

Reduction of the dorsal (back of the body) angle of the thigh to the pelvis, the opposite of „hip flexion„, i.e. a dorsal movement of the thigh in the sagittal plane.

Extension (knee joint)

Reduction of the patella-side (extensor side) angle in the knee joint, i.e. enlargement of the back-of-knee (popliteal) angle in the knee joint up to 180° and possibly beyond (overstretching).

Extension (spine)

Movement that occurs in parts of the spine or the entire spine as a result of the vertebrae tilting backwards in the sagittal plane over several vertebral segments, i.e. the spinous processes move closer together. Extension is possible to a much lesser extent in the thoracic spine than in the cervical and lumbar spine. This is partly due to the plane of movement of the respective facet joints.

Extensors (knee joint, „knee extensors“)

The only extensor of the knee joint is the quadriceps. There are no synergists in either the thigh or the lower leg (in contrast to flexion of the knee joint, where there is the gastrocnemius for supporting flexion).

External rotation / outward rotation (arm)

Turning out the arm in the shoulder joint: in neutral zero moving the biceps and inner elbow forward. See under external rotation for more information. When clapping, for example in concerts or theater, the lunging movement is an external rotation of the arm.

External rotation / outward rotation (leg)

Rotation of the thigh in the hip joint, for more information see just below.

External rotation / outward rotation (hip joint)

Rotation of the thigh that results from the fact that (in relation to standard anatomical position) the inner knee is moved more forwards and the outer knee more backwards. The degree of exorotation capability in the hip joint depends on the movement of the leg in the sagittal plane, i.e. flexion / extension, although much less so than in the case of the dependence of abduction capability on the rotation situation. The capability to turn out (externally rotate) in the hip joint is generally much more pronounced than the capability to turn in. For reasons, see internal rotation in the hip joint.

External rotation / outward rotation (knee joint)

The knee joint allows the lower leg to rotate in relation to the thigh when the knee joint is not extended. When it is, the tension of the collateral ligaments prevents this movement. If it is still possible, this is an indication of collateral ligament damage. External rotation is performed by the only muscle of the outer hamstrings, the biceps femoris. The counter-movement is the internal rotation in the knee joint performed by the inner hamstrings. As a rule, external rotation is somewhat more powerful and possible to a somewhat greater extent than internal rotation.

External rotation / outward rotation (shoulder joint)

Rotation of the humerus in the glenohumeral joint, which is described in standard anatomical position by the fact that the medial elbow rotates forward, i.e. the olecranon rotates medially.

External rotators / outward rotators (shoulder joint)

the muscles that perform the external rotation (outward rotation) in the shoulder joint: infraspinatus, teres minor, deltoideus (with its pars spinalis).

External rotation / outward rotation (shoulder blade)

Movement of the scapula in the plane in which it mainly extends, with the inferior angulus (lower tip) pointing outwards and upwards, which is a prerequisite for raising the arm above 90°. These muscles rotate the shoulder blade outwards. In the yogabook, for the shoulder blade the term otuward rotation is preferred to easily distinguish this movement of the shoulder blade from that of the external rotation of the humerus in the glenohumeral joint.

External rotators / outward rotators (shoulder blade)

Muscles that turn the shoulder blade outwards at the bottom, i.e. into external rotation:

  1. Trapezius
  2. Serratus anterior

In the yogabook the term outward rotation is preferred for the movement of the shoulder blade over external rotation to reserve the latter term for the the external rotation of the humerus in the glenohumeral joint.

External torque

Torque acting on a joint from the outside (not from the body), which acts in the direction of flexion or extension of the joint or as torque in the direction of rotation.


Extremum is the mathematical term for the fact that a function (with not necessarily only a one-dimensional range of values) is smaller everywhere in an environment than at the extreme point (maximum) or is greater everywhere (minimum). The algorithms that describe the yoga poses contain many extremal tasks of the type „stretch the arm with shoulder blade maximally towards the ceiling“, as it is said in urdhva hastasana, for example, or „tilt the pelvis maximally into flexion„, as it is said in uttanasana. As explained in the introduction, many extremes are linked to side conditions that must be fulfilled exactly. For example, the maximum hip flexion in uttanasana requires that the knee joint has a 180° angle, i.e. is anatomically in 0° flexion, as the angle in the knee joint has a serious influence on the capability to flex in the hip joint since the hamstrings are biarticular and span both.


Term for muscles that move the digits of the fingers or toes,
but do not originate in the hand or foot, but in the forearm or lower leg.



see the dedicated article fasciae.

Fibularis group

The fibularis group is a group of pronators of the ankle located in the lateral lower leg (movement takes place in the subtalar joint and subordinately in distal joint lines such as the Chopart or Lisfranc joint line). Fibularis longus, fibularis brevis and fibularis tertius are present in almost all people. A fibularis parvus is considered a variety in which this group is rich. The varieties are differentiated according to their origin because they generally have the same attachment. Most of the origins of the varieties lie distal to the origin of the fibularis longus.

Finger extensors (finger extensors)

Group of muscles that extend the fingers in the metacarpophalangeal (MCP), proximal (PIP) or distal (DIP) interphalangeal joint:

  1. M. extensor digitorum: common extrinsic finger extensor, located in the forearm
  2. Mm. lumbricales (hand): intrinsic flexor, flexes in the metacarpophalangeal joints (MCP), but extends in the proximal (PIP) and distal (DIP) joints; helpful for fine grasping, writing
  3. M. extensor indicis: extrinsic index finger extensor, one of the few extrinsic extensors not originating from the lateral epicondyle

Finger flexors

Group of muscles that flex the fingers in the metacarpophalangeal (MCP), proximal (PIP) or distal (DIP) interphalangeal joint. This group consists of:

  1. M. flexor digitorum profundus (extrinsic): flexes the distal joints (DIP) of fingers 2-5, their proximal joints (PIP), the metacarpophalangeal joint (MCP) and the wrist.
  2. M. flexor digitorum superficialis (extrinsic): flexes proximal joints (DIP) of fingers 2-5, their proximal joints (PIP) and metacarpophalangeal joints (MCP), the wrist and (with very little force) the elbow joint.
  3. Mm. lumbricales (intrinsic): flex in the metacarpophalangeal joints and extend in the proximal (PIP) and distal (DIP) joints; helpful for fine grasping, writing
  4. in the case of the little finger: M. flexor digiti minimi brevis (hand): flexes the proximal joint (PIP)


a flexibility limit in a joint that is given by ligaments is referred to as Firm-elastic, see also under final position.


see dedicated article fitness.

Flexion (elbow joint)

Flexion in the elbow joint, i.e. reduction of the (internal, on the biceps-side) angle between the upper arm and forearm to approx. 30°. While the extension limited is hard-elastic, flexion is usually limited firm-elastic and only rarely soft-elastic. The muscles responsible for flexing the elbow joint are the arm flexors.

Flexion (finger joint)

With the exception of the thumb, there are 2 joints per finger in addition to the metacarpophalangeal joint, a proximal interphalangeal joint (closer to the body, PIP) and a distal interphalangeal joint joint (further away from the body, DIP). Flexion (bending) in the sense of reducing the palmar (internal) angle to possibly 90° is possible in both.

Flexion (hip joint)

Reduction of the frontal (anterior) angle of the thigh to the pelvis, a movement in the sagittal plane. The term „anteversion“ in the hip joint is sometimes used as a synonym. Flexion is performed by the hip flexors, with the hip extensors acting antagonistically.

Flexion (knee joint)

Enlargement of the patella-side (extensor side) angle in the knee joint, i.e. reduction of the popliteal angle in the knee joint. The muscles involved are the knee flexors, i.e. the hamstrings plus the gastrocnemius, the gracilis and the sartorius.

Flexion (neck)

Tilting of the head forward towards the chest, sometimes also referred to as inclination. This is nothing other than the flexion of the cervical spine. The opposite movement is reclination.

Flexion of the spine

Forward flexion of the spine, i.e. reduction of the ventral angle of the vertebral bodies in the sagittal plane. Flexion of the spine in the thoracic and lumbar spine is mainly caused by the straight and oblique abdominal muscles. The opposite movement is the extension of the spine, which is mainly caused by the autochthonous back muscles.

Flexion deficit

Analogous to the extension deficit, whereby the boundary between presence and absence is usually less clearly defined. While the 180° angle is a clear and both geometrically and physiologically plausible limit and nonattainment defines an extension deficit, the case of a flexion deficit is much less simple. After all, many people have more or less pronounced flexibility restrictions not only in the monoarticular muscles that cover their joints, but also in the biarticular and polyarticular muscles, which become relevant depending on the position of the neighboring joints. In addition, in the case of the hip joint, knee joint and elbow joint, extension corresponds to the standard anatomical position and is also frequently taken at least in approximation, e.g. when standing and variably also when walking and in standing handling. The movement-physiological plausibility of the 180° also arises from the fact that in the corresponding joint in the vertical position of the articulation partner, no flexion moment results in the joint from the overlying partial body weight, which in the case of the joints mentioned is likely to be closely causally linked to upright gait.

In the case of a flexion deficit, a limit must be set more or less arbitrarily. If flexion is to be performed actively, often the performing muscles become passive insufficient, which means they cannot flex the joint any further because the antagonists are not flexible enough, so that from a certain point of flexion, their extension moment, which increases with each degree of angle, can no longer be overcome by the agonists, especially as in many cases monoarticular agonist muscles can exert increasingly less force on the descent of the force-length function towards the minimum sarcomere length and thus, in this case, cause increasingly less flexion moment. At a certain point, the agonists then work at such a short sarcomere length that they become actively insufficient and typically begin to cramp. External force can then be applied in an attempt to flex the joint, which should at least prevent the (actively insufficient) agonists from cramping.

If a flexion deficit is suspected, both the actively and passively achievable flexion must therefore be assessed, whereby the latter should in many cases lead to an increasing sensation of stretching in the antagonists with increasing force exerted. For a correct assessment, a possible influence of biarticular and polyarticular antagonists must be excluded in both cases.

Flexors (knee joint, „knee flexors“)

Most of the flexors of the knee joint are located in the back of the thigh: the entire hamstrings, with the exception of the monoarticular caput breve of the biceps femoris, flexes the knee joint (i.e. the muscles semimembranosus, semitendinosus and biceps femoris caput longum), as well as the gracilis , located in the inner thigh and sartorius muscle in the ventral thigh. The tensor fasciae latae also has a flexing effect in the knee joint via the IT band when the knee joint is bent at an angle of more than 30°. Other flexors of the knee joint are the lower leg muscles gastrocnemius and (weakly also) plantaris as well as (very week) the popliteus located in the knee pit, whose main task is to reverse the final rotation, which is why its fibers run transversely rather than longitudinally.


Force is the physical term for a directed effect on a body that can change its direction or position, deform it or cause other changes. Since forces are directed and their strength is a scalar quantity, they can be easily represented as vectors. The direction of the vector is then the direction of the force and the length of the vector, i.e. the mathematical norm, is the strength of the force. Forces can be added vectorially. Opposing forces of equal strength cancel each other out. In a general sense, force refers to the ability to cause something. If a force is exerted along a certain path, this is work. A simple example of this is lifting an object. In order to hold it against gravity, a certain force is required, such as spring tension. This force is opposed to its gravitational force and is equal in magnitude. If the object is now lifted by one meter by exerting more force on it than is required to simply hold it, work is done and the lifted object has a higher potential energy than before. The work performed is therefore equivalent to the increment in energy. If the body is not lifted but heated, it also contains more energy, in this case thermal energy. The concept of work must therefore be generalized so that heating can also be understood as work. This also explains the maintenance of body temperature against the constant loss of heat to the environment. The muscle performs work and consumes energy, the greater the heat dissipation (e.g. at low ambient temperature and insufficient clothing or in the body’s „cooling mode“ during and after greater physical exertion), the more.

In terms of yoga poses, there are many different forces at work, first and foremost the gravitational force exerted by a partial body weight (correct, which acts on a partial body weight) and the tendon force of the muscles, which hold a joint in position or induce movement. However, a muscle functions very differently from a spring balance, a bar or a support, which could be used to prevent gravity-induced movement. According to its construction and control, the muscle is subject to a constant alternation of muscle fibers, which together apply a certain amount of tendon force over time. Therefore, the application of a certain amount of tendon force consumes a certain amount of (chemical) energy over a period of time. If the tendon force required by the muscle is above a certain threshold for a certain period of time, this exceeds the supply or disposal capacity and the muscle begins to tire and burn as a result. The factors of time and tendon force are in relation to each other. It is therefore clear that, in contrast to locked objects, holding an asana costs energy, the greater the forces to be exerted, the more. The energy required comes directly from the reaction of ATP to ADP, i.e. ultimately from food. Another example of energy consumption without any externally visible work being performed is the simultaneous and equally intense tensing of the elbow flexors and elbow extensors, so that no movement results in the elbow joint. In order to achieve and maintain the desired tendon force, other muscle fibers must constantly be brought into action to perform their share of the „holding work“ and consume energy in the process.

Force-length function (often: „force-length relation“)

The force that a muscle can develop is dependent on the current sarcomere length; there is a functional relationship that is roughly described by an upside-down parabola. In reality, this curve is polygonal in small steps: starting at the position of maximum elongation, more and more myosin heads can engage in the actin with increasing contraction and contribute force with their geometric change. Shortly after the maximum contraction force is reached, the opposite effect takes place: the binding sites on the actin, to which the myosin heads can dock, become fewer and fewer until finally actin and myosin have maximally interlocked, actin is running out of further docking places and further contraction is no longer possible. At this point, the contraction force has dropped to zero. There is also a zero point of the function on the other side of the curve (furthest elongation), namely where no myosin head has yet engaged with the actin. The function is often described as being somewhat flatter on the side of greater sarcomere lengths than on the other side. See the force-length function.

Force-velocity-function (Force-velocity-relationsship)

The force that a muscle can exert under comparable conditions (e.g. regeneration status, activation/pre-activation) depends on the contraction velocity. The function that describes this is known as the force-velocity function (also incorrectly referred to as relation) and runs in the second quadrant (negative velocity means eccentric contraction) approximately asymptotically against the eccentric maximum force, has a turning point on the Y-axis (zero velocity means isometric contraction) in the isometric maximum force and runs left-curved against the x-axis with a zero point at maximum contraction velocity. This function is described by the Hill equation:

with v as the contraction speed, F as the muscle force, F0 as the isometric maximum force and empirical constants a,b.
In simple terms, this means that the faster a muscle contracts, the lower its force and the slower the eccentric movement, the greater the force.

Force arm

In terms of biomechanics, this is the lever arm, i.e. the length of the lever on which a force moves a load around a center of rotation.

Forefoot running (bunion running)

Running style usually used at fast speeds and shorter distances. The landing point is just before the body’s center of gravity. The flexion angle in the knee joint is a maximum of 10°, the angle in the ankle is over 90°. Forefoot running requires running shoes with a low drop (the height difference of the heel minus the height of the ball of the foot), a stable longitudinal arch and good muscular equipment. Barefoot rearfoot runners also quickly switch to forefoot running. When switching from other running techniques to forefoot running, adaptation difficulties can occur with corresponding symptoms, apart from sore muscles, this is mainly achillodynia. The wear pattern of the shoes shows the greatest abrasion in the area of the 5th toe. The advantages of forefoot running include better energy efficiency, reduced ground contact time, less need to cushion the landing, better shock absorption by the longitudinal arch of the foot, tendons and muscles of the lower leg, reduced overpronation. Disadvantages are high demands on the muscles and their tendons and a great tendency to overstrain them, especially for forefoot running beginners. Footwear requirements: flat, flexible, low drop, no pronation support, sufficiently flexible and yet stable in the toe area. Greater tendency to Achillodynia, PFPS, metatarsalgia and weakening of the hamstrings. Contraindications for forefoot running are: Hallux valgus, hallux ridigus, kinked foot, flat foot, splayfoot, achillodynia, PFPS, tendency to calf problems.

Free leg / playing leg

The leg not connected to the ground (the one connected to the ground is the standing leg) but performing a posture or movement, see the definition of standing leg.

Frontal abductors of the (shoulder joint)

The muscles that perform frontal abduction (also known as anteversion) in the shoulder joint: deltoid, coracobrachialis, biceps and, under certain conditions (mainly only low degree of present frontal abduction), parts of the pectoralis major.

Frontal adductors of the (shoulder joint)

the muscles that perform frontal adduction in the shoulder joint, i.e: Teres major, latissimus dorsi, triceps (only caput longum), deltoid (pars spinalis, pars acromialis partially) and under certain conditions (mainly low degree of present frontal abduction) pectoralis major.


denotes a direction and means „in front of or towards the front“ and is identical to the term anterior or ventral. The conceptual opposite is dorsal, which in turn corresponds to the term posterior.

Frontal plane

a vertical plane running from left to right through the person in standard anatomical position, i.e. it runs parallel to the plane through the left and malleoli as well as through the left and right acromion.

Functional pain

Functional pain is not a clearly defined term. As a rule, it is understood to mean pain without a detectable non-clinical correlate, which could consist of evidence of inflammation, a fracture, bursitis, a torn muscle fiber, osteoarthritis or other manifest, detectable disorders. Functional pain is often understood to include pain caused by disorders that are detectable by appropriate means but are only slightly noticeable, such as the degenerative symptoms of insertional tendinopathy (enthesiopathy). Classic functional pain includes muscle tension, but also alterations in the capsular or ligamentous tension of the joints. The conceptual counterpart to functional pain is structural pain.

Function test

One of the methods of physical examination: functional testing. This includes many different types of medical functional tests. These include neurological tests, at the simplest for intrinsic reflexes such as the triceps surae reflex (Achilles tendon reflex) or the patellar tendon reflex (quadriceps reflex). It also includes many pain provocation tests (often through stretching or exertion) such as the Payr sign, behavioral tests such as the anterior or posterior drawer test.

Foot deformity

Congenital or acquired malalignment of foot bones: Clubfoot, flatfoot, kinked foot, splayfoot, pointed foot, hollow foot, sickle foot, fallen arches. Foot deformities can be reducible or contractured. If contractural deformities are more pronounced, surgical intervention is usually necessary to prevent consequential damage to other parts of the the musculoskeletal system.



Opening of a joint in a non-physiological direction, e.g. medial gapping of the knee joint refers to the pathological enlargement of the medial joint space, for example in the valgus stress test.

GIRD (Glenohumeral Internal Rotational Deficit / Glenohumeral Endorotation Deficit)

GIRD (Glenohumeral Internal Rotational Deficit) is a glenohumeral internal rotational deficit that is usually not due to shortened external rotators of the shoulder joint but to a thickening and hardening of the dorsal/dorsoinferior joint capsule that has developed in response to certain activities such as throwing. Dorsal hardening pushes the humeral head ventrally, while dorsoinferior hardening can push the humeral head dorsosuperiorly. Dorsal hardening in particular tends to stretch the anterior capsule. In addition to competitive gymnastics, overhead throwing sports are particularly affected. GIRD often occurs in throwers, with the first changes to the dorsal joint capsule occurring after 40 – 60 throws already. It often lead to or is part of a thrower’s shoulder.

It is assumed that the GIRD must be regarded as an early indicator of shoulder problems requiring treatment. The result is a picture of glenohumeral instability, an internal impingement tendency and a predisposition to damage to the glenoid labrum such as the SLAP lesion, often leading to the end of the patient’s career. GIRD is diagnosed when there is a deficit of 20° to the contralateral side.

Giving way phenomenon

Inadequate yielding under load, usually of weight-bearing joints such as the knee joint. In the knee joint, cruciate ligament ruptures and other injuries are common causes of a Givingway phenomenon.


the three gluteal muscles: gluteus maximus, gluteus medius, gluteus minimus.

Golgi tendon organ

Nerve plexus at the transition from the contractile muscle belly to the tendon, which reports the state of tension (generally corresponds to the
tendon strength of the muscle) to the CNS. In the sense of autogenous inhibition, the motor neuron of this muscle is inhibited, i.e. the stimulus for further contraction is dampened, but at the same time the antagonist is stimulated via excitatory switching neurons (interneurons). Autogenic inhibition serves to regulate muscle tension and protect against overstraining. The Golgi tendon organ is one of the proprioceptors.

Gravity perpendicular

The gravity perpendicular is the projection of the center of gravity of a body onto the supporting surface along the direction of gravity. The supporting surface does not necessarily have to be horizontal. If a pose or an arrangement of physical bodies is to be statically stable, the center of gravity must lie in the physical support base. The closer the gravity perpendicular is to the edge of the support base, the less stable the configuration or pose will be. Likewise, the higher the center of gravity is above the supporting surface, more precisely: the greater the distance between the center of gravity and the gravity perpendicular (i.e. the difference in height between the two points), the less stable the pose will be. In both cases, the loss of stability results from the decrease in the tilting moment, i.e. the moment that must be applied to cause the body to tilt, as the lever arm becomes longer with increasing height of the center of gravity and therefore the force required to tilt the body decreases.

Gravity (gravitational force)

For the purposes of our considerations, gravity can simply be equated the gravitational force or mass attraction. The gravitational force is one of the four basic forces of matter. It causes masses to attract each other. It increases linearly with mass and decreases quadratically with distance. Unlike electric and magnetic forces, gravity cannot be shielded and is not influenced by the density of the environment (e.g. a vacuum). On earth, the center of the earth is considered to be the center of gravity, apart from the fact that earth’s surface is anything but round or uniform on closer inspection, as differences in density and height play a role. Gravity is very important for the asanas and their transitions. For example, the gravity perpendicular must lie in the physical base of support if a pose is to be statically stable. In order to maintain most posts (poses such as savasana and viparita karani are exceptions), muscles must work against the gravitational effect of certain partial body weights. This means that some poses cannot be held for any length of time because the muscles cannot provide any amount of strength endurance, examples include urdhva dhanurasana, staff pose or warrior 2 pose. For many transitions in which the physical support base changes, e.g. changing from two to four supporting limbs or vice versa from four to two, gravity implies that these transitions cannot be performed arbitrarily slowly, as the effect of gravity over time will end the transition in between with a different result than the intended one. Examples of this are the jump from downface dog to uttanasana and back or from uttanasana into staff pose as well as the jumping side change in the hip opener 1. Gravity is also important in inversion poses such as headstand, in which blood shifts from the lower to the upper regions of the body, leading to a perceived (and actual) fullness of blood in the head, for example. Further, gravity is important for flexing moments in joints such as the knee joint in virasana or warrior 2 pose.

Gravitational effect

The effect that gravity has on a movement. Although the gravitational force of a partial body weight or a dumbbell is always the same regardless of its position in space and in relation to the human body, the effects that it produces, i.e. the torques generated in joints, and therefore the contraction forces (tendon forces) to be applied by the muscles, vary between zero and a maximum, depending on the angle to the direction of gravity: at an angle of 90° we see the full effect, i.e. the maximum torque, is achieved, at 0° the torque is zero. The effect becomes clear in exercises such as lateral raises and front raises, which are completely light at the start of the movement and become increasingly heavy with increasing abduction towards 90° despite the increase in muscle strength according to the force-length function and the increased lever arm of the deltoid.

Groin pain

Functional pain or structural pain in the groin region. Functional pain is usually caused by insertional tendinopathies of the following muscles:

  1. Adductor longus
  2. Gracilis
  3. Pectineus
  4. Rectus femoris
  5. Iliopsoas
  6. Rectus abdominis

This includes muscles from different functionalities, essentially: Abdominal muscles, hip flexors, adductors. Structural pain, on the other hand, is based on manifest structural disorders such as joint blockages (usually of the SI joint (SI joint blockage), less commonly of the hip joint), osteoarthritis/arthrosis, especially of the hip joint (coxarthrosis), less commonly of the SI joint, disorders of the pubic symphysis, fractures and stress fractures, and in younger people also disorders of the hip joint such as Perthes‘ disease or van Neck disease. In adults, too, it is not uncommon to find disorders that can be traced back to dysplasia and incongruities that were untreated or inadequately treated in childhood/adolescence.

The sports history is often informative and indicative in cases of groin pain. The symptoms are often caused by or during soccer, running sports (especially sprinting and hurdling), and to a lesser extent walking, jumping and martial arts. Acute injuries are often muscle fiber tears or tendon tears (or ruptures). Chronic disorders are often overuse syndromes, such as insertional tendinopathies, joint wear and tear (osteoarthritis/arthrosis) often due to minor disorders of the musculoskeletal system such as axial misalignments, foot deformities, muscular imbalances (e.g. disorders or weaknesses of the hip muscles). During the clinical examination, it should not be overlooked that information on the localization of pain is not always reliable, as e.g. disorders of the hip joint can project in the direction of the knee or of the SIJ in the direction of the groin.

Palpation often reveals tenderness that points to a diagnosis. Functional tests (note the side-to-side comparison!) may reveal pain on stretching or movement restrictions associated with joint pain. Movements performed against resistance usually indicate insertional tendinopathies through pain on exertion if the pain is close to the insertion, otherwise disorders of the muscle itself, which does not fall within the scope of the groin pain disorder. Disruption and reduction of exorotation can be due to muscular causes (contracture/shortening), but can also be associated with disorders of the SI joint if pain is indicated. Internal rotation restrictions, on the other hand, are usually articular in origin and are based on osteoarthritis/arthrosis (usually coxarthrosis), arthritis or capsulitis. If the movements during which pain or restrictions occur are more complex, further investigation is required, and the cause is often ultimately found in the hip joint. Leg length discrepancies are always candidates for causing groin pain. If they are variable (sometimes present, sometimes not), this is often due to a disorder of the SI joint.

Gyroscopic force

The gyroscopic force, or more precisely the gyroscopic effect, is the inertia of an axis of rotation against changes. A symmetrical gyroscope or a rolling wheel stabilizes itself, which is well known to cyclists as the tendency to tip over decreases with speed (all other things being equal). The gyroscopic effect helps to prevent sideways instability in movements such as the one-legged handstand upswing if the swing is performed fast enough.



Constant, repetitive, habitual behavior. This refers, for example, to postural habits such as a hunched back when working at a computer or constantly raised (partially elevated) shoulder blades. Habitual factors can influence and impair the function of the musculoskeletal system and internal organs.

Hamstrings / ischiocrural muscles

see the dedicated page.


A limit of movement in a joint that is given by bones or their cartilage cover is referred to as hard-elastic, see also under end-degree position.

Heart rate

The heart rate is the number of heartbeats (contractions of the heart muscle, first the atria, then the ventricles) per unit of time. It is usually expressed per minute or in bpm (beats per minute). Physiologically, each heartbeat causes a pulse wave in the periphery, so that the pulse measured peripherally coincides with the heart rate. If the measured pulse is lower, there is a pulse deficit.

Heart rate recovery HRR / Recovery pulse

The recovery heart rate is the heart rate at a certain time after exercise, so it would be correct to speak of the 1-minute recovery heart rate, for example, as the heart rate that is metered 1 minute after exercise. The recovery heart rate indicates the rapid regulatory phase of the ability to regenerate. Over time, the heart rate drops exponentially after exercise. Recovery depends above all on the level of performance, the duration, intensity and type of exercise as well as the type of recovery.

Heart rate variability / HRV

see dedicated article HRV.

Heel drop

Drop is the height difference between the heel and the ball of the foot. A high heel drop therefore corresponds to a higher „heel“. The drop of a shoe has an influence on the running style, the load distribution on the muscles and the strain on the musculoskeletal system. Basically, a higher drop results in a lower stroke of the Achilles tendon, a working range shifted towards a shorter sarcomere length and thus a lower utilization of the performance of the triceps surae. In addition, a greater drop hinders rolling the foot at longer stride lengths and higher speeds and would lead to side effects. On the other hand, a moderate drop may be indicated temporarily for achillodynia, but it is not a permanent solution or causal therapy.


the two tarsal bones calcaneus and talus

Hindfoot valgus

Disorder of the foot position with valgus position of the calcaneus and often also other tarsal bones. This disorder is usually based on a tibialis posterior dysfunction syndrome (posterior tibial tendon dysfunction, PTTD) and results in fallen arches or later flat feet. Once the disorder has manifested itself to this extent, a splayfoot often develops and even later a hallux valgus.

Hindfoot varus

Disorder of the foot position with varus position of the calcaneus and often also other tarsal bones. In contrast to disorders with valgus position of the calcaneus, this is significantly rarer and usually occurs with hollow foot or clubfoot.

Hinge joint

see under joint shapes

Hip extensors (hip extensors)

Term for a group of muscles whose function (not necessarily exclusively) consists of extension in the hip joint, i.e. reducing the dorsal angle between the thigh and pelvis. This includes the three-part, mainly monoarticular buttock muscle with its maximus part (only this covers the SI joint with some fiber areas in addition to the hip joint), medius and minimus as well as the semitendinosus muscle, semimembranosus muscle and the biceps femoris with its caput longum (but not caput breve). The adductor magnus also belongs to this group with the fibres that come from the ischial tuberosity.
Antagonists: Hip flexors: iliopsoas, rectus femoris

Hip flexors

Term for a group of muscles whose function (not necessarily exclusively) consists of flexion in the hip joint, i.e. reducing the angle between the thigh and pelvis at the front of the body. In addition to the biarticular rectus femoris pars quadriceps, which also extends the knee joint, these are the monoarticular iliacus muscle, which only covers the hip joint, and the psoas major muscle, which also covers some vertebral joints and the SI joint. Any psoas minor that may be present is only seldom part of the hip flexors, as it usually attaches to the pubic bone instead of the thigh. Even if the adductors also have a slight hip flexor effect (in low degree of flexion of the hip joint only), they are usually not included. The tensor fasciae latae also has a hip flexing effect. However, the strongest hip flexors and therefore the most frequently mentioned are the iliopsoas, consisting of the psoas major and iliacus, and the rectus femoris, part of the quadriceps. The rectus femoris flexes in the hip joint and extends in the knee joint, whereby the movement in the hip joint requires more contraction per degree of flexion than the extension in the knee joint requires. This is due to the different distances of the muscle (in the case of the hip joint) or its tendon/patella (in the case of the knee joint) from the center of rotation in the joint, so wee see different lever arms.

To test the strength of the hip flexors, for example, you can actively lift your straight legs out of savasana, either individually or together. If this is easy and quick, the hip flexors should be strong enough for all everyday situations. If this is difficult or very slow, you can test how strongly a thigh in a supine position with 90° flexion in the hip joint (with the knee joint loosely bent so that the rectus femoris does not cramp) can be moved further towards the chest against external resistance. While the first test primarily tests the strength of the rectus femoris and, secondarily, the tensor fasciae latae, which also flexes the hip (as the distance between the parts of the iliopsoas or its tendon and the center of rotation in the hip joint, the center of the femoral head or the center of the ball of the acetabulum is still very small) the second test primarily tests these muscles, which have an excellent force arm at 90° flexion in the hip joint. If this test is conspicuous in the sense of a lack of exerted (objectively or subjectively assessed) strength, this indicates a lack of strength in the iliopsoas. Physiologically, the force that can be achieved by the iliopsoas at 90° flexion (or the corresponding torque in the hip joint, which is more difficult to measure) is significantly greater than the force to be expected in the first test. In some pathological cases, the test must also be performed in lateral comparison.

The flexibility test is somewhat more difficult. The hip flexor flexibility test provides an initial assessment. If it is successful, sufficient flexibility of the iliopsoas and, for all everyday cases, sufficient flexibility of the rectus femoris can be assumed. The hip flexor flexibility test measures the relevant hip flexors as a functional unit. The rectus femoris is usually the most restrictive, more than the hip flexors in the pelvis (the iliopsoas), as the knee joints are widely flexed. If the flexibility of the iliopsoas is to be assessed with the hip flexor flexibility test set-up, the flexion of the knee joints must be limited to aprox. 90°. The knee joints can then only be lifted passively from the floor by the supporter/examiner. Another test, although its specificity is not ideal, is the hip opener 1 . In this test, the pelvis is lowered as far as possible with the rear knee joint extended, which at a certain point may mean extension in the corresponding hip joint and provides a good indication of its ability to extend if – and this is a real prerequisite or limitation – the hip extensors of the front leg are sufficiently mobile not to hinder the lowering of the pelvis. In practice, there are certainly cases in which the gluteus maximus or the hamstrings of the front leg, for example, prevent further lowering of the pelvis, which becomes noticeable through clear and increasing stretching sensations in the corresponding muscles as the lowering progresses. Other poses to assess the flexibility of the iliopsoas include warrior 1 pose, back arch, purvottanasana, setu bandha sarvangasana and ustrasana. In the latter four poses, the knee joint is bent at 90° at best, so that the rectus femoris is generally not a limiting factor. In addition to the quadriceps stretch on the wall 2, the following orthopaedic tests are also suitable for assessing the flexibility of the rectus femoris:

  1. Thomas handle
  2. Ely Test
  3. Kendall test
  4. Patrick

Intensive use of the iliopsoas can lead to psoas syndrome (sometimes also referred to as leaning) as an overuse phenomenon. If a psoas minor is present and shortened, it can cause a psoas minor syndrome, i.e. depending on whether it is bilateral, a scoliosis or a hollow back.

Hollow back (lumbar spine hyperlordosis)

The spine has two physiological lordoses (concave curves when viewed dorsally, i.e. from the rear) and one physiological kyphosis (convex curve when viewed dorsally). All three curves must not fall below or exceed a certain level in standard anatomical position. A hollow back is generally defined as a lordosis of the lumbar spine that exceeds the physiological level and is often caused by muscular imbalances in the leg/pelvic region, primarily due to shortened hip flexors. In general, these often arise habitually (e.g. due to sitting too long and too often) as well as due to weak leg muscles in childhood/adolescence, but also due to repetitive activities or sports in which the hip flexors are used forcefully or very frequently and repeatedly. See also the article in the FAQ. For the possible effects of a hollow back, see the pathology page.

HSR (Heavy Slow Repetition)

HSR is a strength training technique in which the repetitions are performed slowly in order to achieve good strengthening with minimal side effects. Good strengthening of the tendon tissue should also be achieved with sufficient weight/resistance. A minimum duration of three seconds is set for both the concentric contraction and the eccentric contraction. HSR has proven itself in the movement therapy of insertion tendopathies.


Hyperextension of a joint beyond the 180° angle, which is present in neutral zero. This can occur, for example, in the knee joint, elbow joint, metacarpophalangeal joints or other finger joints. In the toe joints, further extension than the stretched angle in standard anatomical position is part of the rolling movement of the foot when walking and is physiological. Any hyperextension can be associated with non-muscular discomfort, which must be interpreted as a sign of unphysiological stress on joint structures, which requires the position of the joint to be reduced at least to such an extent towards 180° that the discomfort disappears. A certain degree of hyperextensibility, particularly of knee joints and metacarpophalangeal joints, is common, especially in women. This can be due, among other things, to postural habits, which are partly due to the muscular equipment and adaptation to it, see also the FAQ. In other cases, a tendency to hyperextend is anatomically favored, such as hyperextension of the knee joints in the case of a „minus heel“, i.e. a flat heel bone. Pathologically hyperextensible knee joints are referred to as genu recurvatum, elbow joints as cubitus recurvatum.


Hyperkyphosis is a kyphosis of the thoracic spine that is excessively pronounced in standard anatomical position compared to the physiological state. Rarely and with a clearly pathogenic value it also could occur in the lumbar spine or cervical spine. In the case of the thoracic spine, hyperkyphosis is also commonly referred to as a „hump“ or „hunch“.


a lordosis of the lumbar spine or cervical spine that is excessively pronounced in standard anatomical position compared to the physiological state. In the case of the lumbar spine, it is also referred to as a hollow back.

Hypermobility (joint)

Hypermobility of a joint is an angular excess flexibility in one or more movement dimensions of a joint. By definition, it is not instability and is not pathogenic, but can predispose to the development of instability. The term hypermobility is often used carelessly. Physiological flexibility in the joints is stated inconsistently by anatomists, but hyperextension of the knee and elbow joints is usually considered physiological up to a certain degree, which is stated differently by the authors. The diagnosis of hypermobility (excessive flexibility) is often made lightly and identified as the cause of existing complaints. In the absolute majority of cases, however, it is not a case of genuine hypermobility in the sense of a hypermobility syndrome – such cases are very rare and frequently occur in the context of Ehlers-Danlos syndrome or Marfan syndrome – but only of flexibility that exceeds the population average and is not in itself pathological or pathogenic.


excessive pronation when running/walking. It predisposes to a number of disorders in the lower limb, especially if the limb is used more intensively: DGS (Deep gluteal syndrome/piriformis syndrome), plantar fasciitis, heel spur, runners knee, achillodynia (Achilles tendon irritation), tibial plateau syndrome, (medial) meniscus damage, pes anserinus syndrome, but contrary to previous opinion, not for PFPS (chondropathia/chondromalacia patellae).
Of the three phases of a foot’s contact with the ground when walking or running (landing phase, support phase, push-off phase), the middle phase, the support phase, is the one in which overpronation, i.e. excessive lowering of the inner foot in relation to the outer foot, is recognizable and comes to bear. This results in excessive strain on the medial structures of the leg system. Around half of all runners are affected by hyperpronation, women more than men. Talipes valgus, flat feet, overweight and fatigue can lead to hyperpronation, as can supinator weakness or overcrossing when running. Special models of running shoes are available for hyperpronators. Beginners are more frequently affected. Hyperpronation is a risk factor for some disorders and injuries in the lower limb, see above.


Excessive supination when running and walking. Only 2-3% of runners are hypersupinators. It is a risk factor for some disorders and injuries in the lower limb, especially if it is used more intensively: (medial) meniscus damage, supination trauma.
Hypersupination puts excessive strain on the lateral structures of the leg system and predisposes to supination trauma. As a rule, there are no special models of running shoes available for supinators, partly because this group is very small, and partly because if the shoe provides sufficient dorsal guidance of the foot, the foot can be prevented from floating outwards, thus avoiding kinetics that favor supination trauma. Bow legs, hollow feet, insufficiency of the foot and lower leg muscles and weak ligaments can predispose to supination.


A hypomochlion is a body structure, such as a part of a bone or a retinaculum, which increases the lever arm of a muscle or its tendon. These can be bone edges, bony protrusions, incisures or a sesamoid bone. A bony hypomochlion is, for example, the patella, the pisiform bone or the sesamoid bones of the hallux.


The ball of the hand opposite the thumb on the side of the little finger with its musculature:



the therapeutic immobilization of an area of the body, for example after fractures or illnesses or for the purpose of transporting seriously injured people in order to prevent further damage that is difficult to foresee. This can be done using aids such as splints or casts or a stretcher with straps.


Impingement refers to the pathological (and fundamentally pathogenic) contact of one structure, usually a bone, with another structure. Common impingements include those of the shoulder joint (known as subacromial impingement ) and the hip joint (known as femoroacataluar impingement FAI).


denotes a position close or (in comparison) closer to the feet. The conceptual opposite is superior. The term thus goes beyond the term caudal, which refers to a position close to the lower end of the trunk.


Some anatomical structures are present in all people; these are called constant. Those that are not regularly present are called inconstant. Examples include certain ligaments such as the medial transverse retinaculum of the knee joint or bursae, which only become pronounced when a structure is stressed.


The body’s own reaction to harmful stimuli. These stimuli can be

  1. Chemical (acids, alkalis, toxins, enzyme exposure as in pancreatitis)
  2. Physical (pressure, friction, trauma, foreign bodies, metabolic products such as uric acid crystals (e.g. in gout), heat, cold)
  3. Traumatic
  4. Germs (bacteria, viruses, fungi, parasites)
  5. Allergens
  6. Autoallergens (triggers of rheumatic and autoimmune diseases)

Inflammations not caused by pathogens are referred to as aseptic. Inflammation is a reaction of the body with which it attempts to restore the initial physiological state, which is why it is also referred to as an inflammatory reaction. For repair, the affected area must be supplied with more blood and the pores of the membranes must be widened by appropriate inflammatory mediators so that immune cells (leukocytes) can flow into the area. Terminologically, the suffix „-itis“ is added to the anatomical name of the inflamed anatomical structure. Not all inflammatory processes make sense from a medical perspective. There are also autoimmunological inflammatory processes in which the body damages healthy endogenous cells. This misbehavior is due to a malfunction of the immune system in which, for example, antibodies previously formed against a pathogen also act against the body’s own tissue as part of a cross-reaction. Inflammation can occur in organs, the surrounding connective tissue, blood vessels and lymph vessels. There are 5 typical signs of inflammation:

  • Dolor (pain)
  • Calor (overheating)
  • Rubor (redness)
  • Tumor (swelling) and
  • Functio laesa (Functional limitation)

Depending on how pronounced or voluminous the inflamed tissue is and how deep it is in the body, some of these 5 signs may not be perceptible.

– Signs of inflammation

There are 5 typical signs of inflammation:

  • Dolor (pain)
  • Calor (overheating)
  • Rubor (redness)
  • Tumor (swelling)
  • Functio laesa (Functional limitation.)

Depending on how pronounced or voluminous the inflamed tissue is and how deep it lies in the body, some of these 5 signs may not be perceptible. Rubor and tumor are due to increased permeability (mediated by interleukin-1 and prostaglandin I2), which causes increased plasma and blood cells to enter the tissue. Dolor is caused by pain messengers such as prostaglandin E2, prostaglandin I2, bradykinin and other kinins as well as cytokines (tumor necrosis factor) and is intended to protect the affected area. Calor is caused by the increased metabolic activity mediated by cytokines such as interleukin-6 (via the production of prostaglandin E2). In some cases, irreparable cells are abandoned (apoptosis, programmed cell death) or parts of tissue necrotize so that new cells can replace them. Under unfavorable conditions, pathogens causing inflammation can escape the local immune system and spread through the bloodstream to afferent tissues (sepsis) or lead to inflammation in the lymphatic tract (lymphangitis). Therapeutically, it must be examined whether the inflammatory process should be influenced so that the symptoms are alleviated, or whether the body should carry out the repair undisturbed according to its own mechanisms, which may lead to faster healing.


The area of a bone where a ligament or the tendon of a muscle is fixed. In the case of a muscle, the proximal insertion is called the origin and the distal insertion is called the attachment, without distinction we talk of insertion. Some muscles insert non-tendinously to a bone, such as the origin of the iliacus in the iliac fossa of the ilium.


One of the methods of physical examination is visual evaluation or visual assessment. There are numerous examples of this, such as observing the straightness of the spine in poses, the parallelism of the tendons of the middle fingers or the midlines of the feet, the height of the hip bones or shoulders in a side-by-side comparison (is one of them higher?), the assessment of an angle, such as of the midlines of the feet, but also the silhouette, such as the gluteus maximus in the upface dog, the width and height of which allow conclusions to be drawn as to whether the gluteus maximus contributes to extension or reduction of flexion in the hip joint. Inspection of the trapezius line also provides an indication of whether the shoulder blades are elevated in the warrior 2 pose, depressed or in a position in between. In many cases, inspection of the spine provides important information about the presence of scoliosis, while inspection of the pelvis in symmetrical standing poses provides information if pelvic obliquity is given. In supta virasana , one ASIS is often elevated in relation to the other or one leg visibly deviates into abduction while the other is in adduction or straight. The inspection then forms the basis for further investigation, such as for the force with which the deviation occurs. Many assessments based on inspection can only be made relatively, i.e. by side-by-side comparison or comparison with a final position.


Inhalation. This takes place at a slow pace in an upright posture with the help of the inspiratory respiratory muscles, starting with the scaleni, which may already be sufficient for a light inhalation; with a somewhat stronger inhalation, the intercostal muscles, among others, are involved, and the inspiratory auxiliary respiratory muscles are added in a forced inhalation. Inhalation (inspiration) in general consists of two parts, thoracic and abdominal inspiration. During thoracic inspiration, the ribs are raised cranially and ventrally, which enlarges the thorax and draws air into the lungs: without incoming air, there would be lower pressure in the lungs than in the surroundings; the incoming air compensates for this. Abdominal inhalation is caused by contraction of the diaphragm, which contracts caudally and thus also increases the lung volume, as the lungs are caudally fixed to the diaphragm. In lung function diagnostics, the inspiratory vital capacity, i.e. the maximum volume of air that can be inhaled after forced expiration or, conversely, the maximum volume of air that can be exhaled after forced inspiration, is determined in order to investigate restrictive lung diseases.

The following diagram shows the expanded and forced inspired position of the ribs from the cranial side with the axes of movement resulting from the joints on the vertebra.

The lateral view clearly shows the lifting movement as well as the change in inclination in the sagittal plane:

Inspiratory auxiliary respiratory muscles

Muscles that can also be used during powerful inhalation:

  1. M. levatores costarum
  2. M. serratus anterior (anterior saw muscle)
  3. M. serratus posterior superior (posterior superior saw muscle)
  4. M. pectoralis minor and pectoralis major (the latter only when the arm is supported)
  5. M. sternocleidomastoideus
  6. M. erector spinae

Inspiratory respiratory muscles

Muscles that are used during normal inhalation:

  1. Diaphragm (diaphragm)
  2. Mm. intercostales externi (external intercostal muscles)
  3. M. scaleni
  4. M. intercartilaginei (the part of the inner intercostal muscles between the rib cartilages)

Inspiratory reserve volume

the volume that can be additionally inhaled after calm, relaxed inspiration.

Instability (joint)

Congenital or developed ability of a joint to move in a dimension other than the physiological dimensions of movement. The cause is usually an insufficiency of the passive musculoskeletal system, i.e. the ligaments and the joint capsule. It can be caused by trauma, a lack of training stimuli (underuse), degenerative processes (causes: inadequate trophism, lack of training stimuli, overuse, physiological ageing) or pain (interferes with proprioception and therefore also with joint control) or be the result of illness or injury (causes: iatrogenic in arthoscopies, surgical intervention; everyday trauma, sports injuries). Instability is always pathological and usually also pathogenic. In the case of the knee, for example, insufficiency of the collateral ligaments can lead to varus and valgus movements in the knee joint as well as to transverse translation of the tibia in relation to the femur. In the first case, even more so than in the second, articulation is partially lost, meaning that the joint surfaces have noticeably to dramatically reduced contact, which leads to significantly increased stress on the bones and their cartilage coverings. This is a cardinal difference to hypermobility, in which the angular dimension of one or more physiological movement dimensions is increased, but the movement still takes place (at least to a large extent) on the intended cartilage surfaces.

Intercostal muscles

Intercostal musclesare muscles between the rips that are used for breathing:

  1. Mm. intercostales externi (external intercostal muscles), superficial, inspiratory
  2. Mm. intercostales interni (internal intercostal muscles), profound, expiratory
  3. Musculi intercostales intimi, separation of the Mm. intercostales interni, expiratory
  4. Musculi subcostales, derivatives of the Mm. intercostales interni, expiratory
  5. Musculus transversus thoracis, influences the elasticity of the rib cage by tensing the rib cartilage

Internal rotation / inward rotation (leg)

Turning the femur in in the hip joint, for more information see internal rotation (hip joint).

Internal rotation / inward rotation (hip joint)

Rotation of the thigh that results from the fact that (in relation to standard anatomical position) the inner knee is brought backwards and the outer knee forwards. The degree of possible internal rotation in the hip joint depends very little on the movement of the leg in the sagittal plane, i.e. on flexion/extension, quite unlike the possibility to abduct depends on the rotation situation, for example. The ability to turn the leg in in the hip joint is generally much less pronounced than the ability to turn it out.

This may be due to human movement behavior since time immemorial: internal rotation of a leg when walking or running leads to the legs bumping into each other even at a slight angle. In contrast, external rotation of the legs is already obligatory for a quick change of direction while running, but even more so for sitting postures such as the cross-legged position. A low center of gravity is advantageous for lifting an unstable object, so the knee joints are bent. If the object is very heavy, the center of gravity of the object should be close to the center of gravity of the body, which is not possible when the knee joints are bent forward, but only when the knee joints are bent to the side with the legs open. This is likely to have been another important factor in the history of mankind, which is why a capability to turn out the leg wide developed in the hip joints.

Internal rotation / inward rotation (knee joint)

Internal rotation of the lower leg in the flexed knee joint is performed by the muscles of the inner hamstrings: semimembranosus, semitendinosus, furthermore the gracilis, and additionally the sartorius, i.e. all muscles that attach to the pes anserinus. For the countermovement, see external rotation in the knee joint. In the extended state of the knee joint the collateral ligaments and the cruciate ligaments prevent any rotation.

Internal rotation / inward rotation (arm / shoulder)

Turning the arm in in the shoulder joint: in neutral zero moving the biceps and inner elbow backwards. For more information, see here.

Internal rotators (arm / shoulder)

the muscles that turn in the upper arm in the shoulder, i.e. in standard anatomical position the inner elbow is rotated medially. These are subscapularis, pectoralis major, deltoideus (pars clavicularis), teres major, biceps (caput longum), latissimus dorsi.

Inward rotation / internal rotation (shoulder blade)

Movement of the scapula in the plane in which it mainly expands, with the inferior angulus (lower tip) downwards-inwards, which reverses the outward rotation, that is, returns the scapula from the outward rotated position in which it is when the arm is raised far. These muscles rotate the scapula inwards.

Inward rotators / internal rotators (shoulder blade)

Muscles that perform the internal rotation of the shoulder blade:

  1. Latissimus dorsi (indirect)
  2. Levator scapulae
  3. Pectoralis minor
  4. Pectoralis major (indirect)
  5. Rhomboideus major
  6. Rhomboideus minor

Interspinal system

the muscles that run between the spinous processes of various vertebrae and belong to the medial tract of the autochthonous back muscles: Interspinalis (lumborum, thoracis, cervicis) and spinalis (thoracis, cervicis, capitis).

Intertransversal system

the muscles that run between the lateral transverse processes of different vertebrae and belong to the lateral tract of the autochthonous back muscles: intertransversarii lumborum (mediales and laterales), thoracis, cervicis (anteriores and posteriores), which, innervated unilaterally, flex the spine laterally and extend it when innervated on both sides.

Intervertebral disc (spinal disc, discus)

Elastic cartilaginous buffer between bones, which serves to improve pressure distribution and increases the contact surface of the cartilage coverings of the bones, thus reducing possible wear and tear. There are intervertebral discs between vertebral bodies, but also in classic joints such as the wrist and the acromioclavicular joint. Together with the articulating bones and the associated ligaments, the intervertebral discs are symphyses. The functional principle can be clearly seen in the example of the large intervertebral discs between the vertebral bodies: the nucleus pulposus is highly water-binding, so that the liquid part distributes the pressure as evenly as possible between the interfaces according to Pascal’s principle. This keeps the point pressure low and consequently the wear. See also the intervertebral disc between the vertebrae.


Term for muscles that move the phalanges of the fingers or toes and originate in the hand or foot.

Inversion (foot)

Inversion is the sum of movements in the upper and lower ankle joint, consisting of supination, plantar flexion and adduction of the foot.

Isometric contraction

Muscle contraction in which the position of actin and myosin in the sarcomeres and the distance between the M- and Z-discs remain unchanged and therefore the distance between the origin and attachment of the muscle remains the same. In addition to isometric contraction, there is also eccentric, concentric and isotonic contraction.

Isometric muscle failure

the middle of the three kinds or stages of muscle failure: the inability to maintain a given isometric contraction. For an explanation and example, see muscle failure.

Isotonic contraction

Muscle contraction in which the tension of the muscles (contraction force) remains the same. Whether an eccentric or concentric contraction results, i.e. whether and how the distance between the origin and attachment of the muscle changes, depends on the external resistance to the contraction. This includes not only forces acting on the body from the outside but also the tension of the antagonist(s). In addition to isotonic contraction, there is also concentric, eccentric and isometric contraction.



see the dedicated page on jogging

Joint shapes

See the separate page on joint shapes


Kinetic energy

The energy stored in the movement of a body. If the body is decelerated abruptly, this energy is converted into heat or cold deformation, for example. The speed is included as a quadratic factor in the energy of the body, while the mass is included as a linear factor. In order to accelerate a body, energy must be used, which is then contained in it as kinetic energy, i.e. one form of energy is converted into another.

Kinetic load

The term kinetic load, which is not commonly used in physics, is used here to describe a load that is caused by a moving body instead of a body at rest. The meniscus of the knee joint serves as an example. In anatomical zero, the load on each (left and right) of the two menisci of the knee joint is 42-45% of the body weight, or around 350 N per knee, depending on the literature used. During jogging or running, each leg is alternately unloaded as a free leg in the flight phase and then loaded again in the standing leg phase.

When the leg is lifted using the strength of the hip flexors at the start of the free leg phase, the meniscus and the cartilage of the tibia and femur is relieved by the inertia of the lower leg and foot so that at the beginning of the standing leg phase it is not only loaded again with the above-mentioned part of the body weight, but also with the mass inertia of the above
partial body weight (torso, head, arms) after the foot is placed on the ground.

The kinetic energy contained therein must be absorbed by the meniscus and the two cartilages of the tibia and femur. This hardly happens in the form of heat energy, but mainly in the form of elastic deformation of these cartilages. This phenomenon is intensified by the fact that the body’s centre of gravity oscillates in height, i.e. is at its highest approximately in the middle of the flight phase. Kinetic load refers to the effect that, in addition to the static load (weight force of the supported partial body weight), there is a kinetic energy that is dependent on the square of the speed, which leads to a significantly greater effect (e.g. elastic deformation or kinetic energy) beyond the effect of the static weight force (e.g. elastic deformation or non-elastic deformation such as cracks) on the supporting structures.

Knee lift

The extent to which the leg is lifted when running. Too little knee lift is usually the result of muscular weaknesses in the leg and hip flexor muscles. It predisposes to circumduction of the leg and various joint problems.


Hunchback; the kyphosis can be physiological (kyphosis of the thoracic spine) or pathological (e.g. hyperkyphosis of the thoracic spine or kyphosis of the lumbar spine or cervival spine). More about this on the pathology page.



A labrum is a cartilage lip. Such structures are particularly necessary where a very small, flat joint surface has to hold a bone with a large radius/circumference. Examples include the two large joints on the trunk with a large range of motion: the hip joint and the shoulder joint, where the shoulder joint requires a labrum much more urgently than the hip joint.

Lactate threshold

The lactate threshold is the maximum load at which the same amount of lactate can be removed as is produced. It represents the beginning of the anaerobic zone, which generally starts at 80% of maximum performance capacity. From this threshold onwards, an increasing oxygen debt and an increasing accumulation of lactate in the muscle are unavoidable.


Mechanical force transducer consisting of a rigid body that can be rotated around a fixed point (rotation center). A force applied to the body is converted into a rotary motion, whereby the applied force is converted into a torque.

Lever arm

The distance between the rotation center and the point at which the force of a lever is applied is referred to as the lever arm.

Leverage principle / law of the lever

For a lever in equilibrium, the sum of all applied torques (with respect to an identical reference point) is zero. In the case of a two-point lever, this is known as „force * force arm equals load * load arm in general“, where force arm or load arm are lever arms and mean the distance of the point where the force is applied or the load is moved resp. to the rotation center.

Load arm

In terms of biomechanics, this is the lever arm on which a load moves around a center of rotation, i.e. usually the distance of the object’s center of gravity from the center of rotation.


denotes a position far or (in comparison) further away from the center, seen in the transverse plane. The conceptual opposite is

Lateral abductors of the (shoulder joint)

the muscles that perform lateral abduction in the shoulder joint: deltoid with all three heads, strongest with the pars acromialis, supraspinatus (even before the deltoid can build up a remarkable moment), biceps (weak with the caput longum).

Lateral adductors of the (shoulder joint)

the muscles that perform lateral adduction in the shoulder joint: triceps (caput longum only), teres minor, teres major, latissimus dorsi, deltoideus (partly with pars spinalis and pars clavicularis), pectoralis major.

Lateral tract

Part of the autochthonous back muscles: intertransversal system, spinotransversal system, sacrospinal system and the levatores costarum.

Lateral flexion

Lateral flexion of the spine. This is possible in all parts of the spine, depending on their different flexibility, i.e. it is least pronounced in the thoracic spine and most pronounced in the cervical spine. Depending on the area of the spine, various lateral flexor muscles cause lateral flexion of the spine; for a list, see lateral flexors.

Lateral flexors

The muscles that perform lateral flexion, i.e. lateral bending of the spine. These are

  1. General: oblique abdominal muscles, latissimus dorsi, quadratus lumborum, as well as the oblique system of the autochthonous back muscles: spinalis, semispinalis, longissimus, iliocostalis, multifidi, intertransversarii, interspinales.
  2. Specifically in the thoracic spine: Levatores costarum
  3. Specifically in the lumbar spine: psoas major, if present also psoas minor
  4. Specifically in the cervical spine: sternocleidomastoid, levator scapulae, scalenus anterior, scalenus posterior, scalenus medius, rectus capitis anterior, also autochthonous muscles: longus colli, splenius, obliquus capitis superior, rectus capitis posterior minor, rectus capitis lateralis

Lateralization (shoulder blade)

Maximum lateral movement of the shoulder blade, i.e. away from the spine without pulling it clearly forwards. This position is clearly far from retraction, but also far from protraction. It is usually most easily achieved when the arm is stretched outwards away from the spine at around 90° lateral abduction, as is the case in 2nd warrior pose or trikonasana. If the arm were moved from the position in which it is in the warrior 2 pose (90° lateral abduction) in the sense of a transverse adduction maximally forwards and later medially, the shoulder blade would begin to move into protraction at around 20° adduction if the flexibility is good. With less good flexibility, it may start earlier.
Lateralization is also possible in maximum frontal abduction, e.g. in caturkonasana, when the palms are pressed together forcefully. The difference between lateralization and protraction can easily be demonstrated experimentally if the arm is maximally adducted transversely from lateralization with the arm raised to 90° lateral abduction.

Leg length discrepancy

see the dedicated article leg length discrepancy.


A fibrous, barely stretchable strip of connective tissue that limits the relative movement of movable parts of the human musculoskeletal system. The main component of ligaments is collagen. Ligaments are found in the joints to set firm-elastic limits of movement between bones in joints and thus define the maximum geometric range of motion, which is then more or less restricted by muscles in the sense of soft-elastic limits of movement. They also act as retinaculi (restraining ligaments) to keep tendons close to joints or bones so that they – and their muscles – do not tend to run across three-dimensional space in the shortest possible distance. Retinaculi also limit the flexibility of the patella in the knee joint, as the patella would have a strong tendency to dislocate if the quadriceps were not tensed. If ligaments are subjected to excessive tensile stress, they become overstretched or even tear or rupture.

An overview of the ligaments, sorted according to the joint to which they belong, can be found here, else see the corresponding joint.

Limit of movement

The limit of movement is the point and type of stop of a movement based in the joint or the muscles spanning it, see also under terminal:

  1. soft-elastic: muscular
  2. firm-elastic: ligamentous
  3. hard-elastic: the bone or the cartilage covering of the bones

Linea alba

The „white line“ between the two left and right parts of the rectus abdominis, i.e. the midline of the abdomen. It therefore lies in the median plane. Physiologically, it runs exactly vertically in standard anatomical position. Deviations from this need to be clarified. A curvature of the linea alba, for example, usually indicates scoliosis, while a deviation from the vertical in standard anatomical position indicates a difference in leg length. It is not uncommon for both to occur together, as leg length discrepancies tend to cause pelvic obliquity and, consequently, scoliosis.

Linea terminalis

The curve formed by the promontorium of the sacrum, pars lateralis of the sacrum, linea arcuata, eminentia iliopubica, pecten ossis pubis, tuberculum pubicum and symphysis, which separates the lesser pelvis cranially from the greater pelvis.

Lisfranc joint line

The Lisfranc joint line is the line connecting the joint surfaces of the bases of the metatarsal bones, that is, the line between the tarsus and the metatarsal bones, see under ankle joint: Lisfranc joint line

Load intensity

Load intensity is a variable that must be defined differently for different types of exercise. In the case of strength training, it is determined by the number of repetitions. In descending intensity, this is plotted against the number of repetitions as follows (Rühl, 1992):

  1. 100% – 1
  2. 95% – 2
  3. 90% – 3-4
  4. 85% – 5-6
  5. 80% – 7-8
  6. 75% – 9-10
  7. 70% – 11-13
  8. 65% – 14-16
  9. 60% – 17-20
  10. 55% – 21-24

100% is the load intensity that just allows a single repetition (in succession without regeneration time, the so called one repetition max.). If you are not working with repetitions of cyclical movements, but instead maintain isometric load over time, you must specify the minimum time interval to which 100% is assigned, which could be one second, for example. In general, the times until isometric muscle failure occurs are specified. When using external weights, a weighting depending on the weight is obvious. This does not necessarily have to be linear. All lower load intensities must then be assigned longer times, whereby the maximum time interval of an isometric load is likely to be quite individual, and in quite a few cases also dependent on other internal (e.g. tone of the antagonists) or external factors (e.g. temperature). In the case of stretching, the subjectively perceived intensity must be evaluated, for example using the usual Numerical Rating Scale (NRS), which is also used for the evaluation of pain or other symptoms, in which the numbers 0 (no intensity / sensation / discomfort at all) to 10 (strongest imaginable pain) are evaluated. Only two values are given a priori:

  1. 100% – 10
  2. 0% – 0

In addition, the assignment can be linear, logarithmic or otherwise non-linear. In addition to the load intensities mentioned, other constructs can also be defined, such as the load in watts (W) when cycling or the speed cycled or the running pace under specified conditions.

Locomotor system / Musculoskeletal system

see Musculoskeletal system

Long bone

see Tubular bone

Longitudinal muscle adaptation

The number of sarcomeres in a myofibril is not a fixed value that remains constant throughout life. The use of the musculoskeletal system does have an influence on this. For example, muscles that are immobilized in a short sarcomere length over a longer period of time (usually as a result of trauma) reduce the number of serial sarcomeres (i.e. those lying one behind the other in the myofibril), thus reducing their number. Similarly, more frequent intensive use of the muscle in larger sarcomere length is likely to increase the number of serial sarcomeres. This is referred to as longitudinal muscle adaptation, in contrast to the long-known growth in muscle thickness through training, in which the number of parallel sarcomeres increases. The consequences of the (reversible, see above) longitudinal muscle adaptation result from the fact that more sarcomeres in a row now perform the same work as before and, as far as is known today, are all positive:

  1. favorable shift of the working range of the individual sarcomeres in terms of the force-length function
  2. Slight increase in muscle performance
  3. Slight increase in maximum strength
  4. Slight increase in maximum contraction speed
  5. Slightly reduced susceptibility to injury

For examples of poses that typically cause longitudinal muscle adaptation, see the explanation under muscle soreness.


convex from the front (ventral) or concave from the back of a part of the spine, physiologically this is the case to a certain extent in the lumbar spine and cervical spine

Lumbar spine

The lumbar spine is the part of the spine directly above the sacrum, usually consisting of 5 vertebrae, but lumbarization of sacral vertebrae or sacralization of lumbar vertebrae or even a supernumerary lumbar vertebra are not uncommon.
Due to its position above the sacrum, which is further ventral cranially, the lumbar spine physiologically curves in a concave lordosis (seen from behind). Permanent upright position or kyphoses of the lumbar spine are pathogenic. The lumbar spine is an important area of origin for an important hip flexor, the psoas major, which, when shortened, hyperlordoses the lumbar spine instead of (only) physiologically lordosing it. In contrast to the thoracic spine, the lumbar spine is free of rib attachments.

Lymphatic system / Lymphatic system

The system consisting of the lymph nodes containing lymphatic tissue and the lymphatic vessels, which represents a return route (alternative to the veins) from the interstitium to the heart.


Lymph is a milky yellowish fluid that transports high molecular weight substances, cell debris, leukocytes and the remains of pathogens. It is formed from interstitial fluid and is finally filtered by lymph nodes and fed into the bloodstream.

Lymph is an aqueous fluid that serves to remove certain substances from the interstitium of the tissues that must not be transported in the venous bloodstream because they are or may be infectious or because they are hydrophobic. These include certain blood proteins, fatty acids, metabolic or inflammatory products. Substances with a large molar mass, which cannot be transported venously due to the limited size of the pores in the membranes, are also transported by lymph vessels. The dietary fats that accumulate in the digestive tract during fat metabolism are transported in the lymph in the form of chylomicrons. Because of the substances it contains, the lymph is light yellow/milky in color. The lymph vessels contain lymph nodes which, among other things, inactivate pathogens in the lymph.

The flow rate of the lymph is approx. 2-3 cm / hour, the lymph produced daily is approx. 2-3 liters. At 7.41, its pH is barely higher than that of the blood. As a filtrate of the interstitial fluid, the lymph also contains
urea, creatinine, glucose, sodium, potassium, phosphate and calcium ions, enzymes such as amylases, catalase, dipeptidases and lipases, as well as fibrinogen and other coagulation factors that enable the lymph to clot in the event of stasis (see Virchow’s triad). Lymph production can be accelerated with lymphagoga (lymphatic stimulants) such as egg white, bile, peptone, salts, urea and sugar. Physiologically, the lymph together with the venous returning blood amounts to exactly
as much as the arterial blood flow. If the flow of lymph is impeded or restricted, lymphoedema occurs. Due to the much lower flow velocity or the much lower return flow volume per time, lymphoedema develops much more slowly than venous oedema.

Lymph nodes

Lymph nodes are accumulations of lymphatic tissue (reticulum cells, lymphocytes, antigen-presenting cells), typically 5 – 10 mm in size, with activity also up to 20 mm and larger. All mammals have lymph nodes, sometimes in significantly different numbers and sizes. Humans usually have 300 – 700 lymph nodes. After an initial unspecific phagocytosis of certain parts of the primary lymph, the differentiation of lymphocytes is stimulated in them, so that T-, plasma and memory cells are finally available in the bloodstream via the secondary lymph and the right venous angle. All regions of the body have regional lymph nodes that dispose of a corresponding tributary area, see this map. Swelling of the lymph nodes indicates an immune response, i.e. usually an infection.

Lymph node swelling

Increase in the volume of lymph nodes. The lymphatic tissue in the lymph nodes becomes active, particularly in the case of inflammation and malignancy, and there is an increase in volume, which can be felt subjectively with more or less pronounced tenderness and tension pain, and which is palpable in superficial lymph nodes. Painful enlarged lymph nodes with a local inflammatory process are usually caused by an infection. Less frequently occurring painless, progressive swelling of the lymph nodes, on the other hand, often indicates a malignant process. A further distinction is made according to duration, 1-2 weeks: acute, 2-6 weeks: subacute, over 6 weeks: chronic, and according to occurrence: local or regional, e.g. in sentinel lymph nodes or, if more than two non-contiguous lymph nodes are affected: generalized. In the case of lymphomas, the cause lies in the lymphatic tissue of the lymph node itself, otherwise the cause of the swelling lies in the tributary area.

Lymph vessel / lymphatic duct

The vessels in which the lymph flows from the interstitium of the tissues to the heart (venous angle) and in which substances, particles and pathogens are transported that must not enter the venous bloodstream (and subsequently the arterial bloodstream). Lymph nodes are located in the lymphatic vessels; in the case of lymphatic vessels that dispose of exactly one organ, they are referred to as sentinel lymph nodes. Some regions of the body have their own lymph nodes. All lymph flows via the thoracic duct, the largest lymphatic vessel, to the Virchow lymph node (also incorrectly referred to as the „Virchow gland“) and from there directly into the venous angle of the right heart and thus into the circulating bloodstream. Similar to the veins of the extremities, the lymphatic vessels only have valves that open towards the heart which serve to transport the blood back to it.


Malleolus fork

The „fork“ formed by the tibial and fibular malleolus, which surrounds the talus and thus the first tarsal bone.


It can sometimes be observed that typical effects of a pose do not occur because other statistically and physiologically less likely difficulties prevent them from appearing. Once these difficulties have been overcome, the typical effect then appears. This behavior is called masking of the statistically and physiologically expected phenomenon. Masking phenomena are often the result of the use of the musculoskeletal system in everyday life, work and sports behavior in terms of the activities performed and postures adopted.

Masking cascade

a sequence of masking effects, all of which mask a typically expected effect as well as each other. When the first masking effect is overcome, the second becomes visible, after its release the third, and so on. Once the entire masking cascade has been released, the typical, statistically and physiologically expected effect occurs.

(Mass) inertia

The ability of a rigid body in motion to continue this motion without automatic acceleration or deceleration (which is negative acceleration). If no external forces (such as air resistance or gravity) were acting on the body, it would continue to move in an infinitely linear fashion. As this law applies to both positive and negative acceleration, acceleration from rest is also covered. If it is a rotary motion, it is referred to as an inertia torque or moment of intertia.

Maximum heart rate / HFmax

There are various formulas for estimating the maximum heart rate depending on age and other factors:

  1. Spanaus (for athletes): 226 – 1.0 × age (women) or 223 – 0.9 × age (men)
  2. Tanaka (for athletes): 208 – 0.7 x age
  3. Hossack: 206 – 0.597 x age (women) or 227 – 1.067 x age (men)
  4. Edwards: 210 – 0.5 × age (in years) – 0.11 × body weight (women) or 214 – 0.5 × age – 0.11 × body weight (men)

The formulas are less accurate for athletes with decreasing age and more accurate with increasing age, even if very significant deviations are possible in individual cases. In contrast to the calculation of the training zones, the resting heart rate is not relevant for determining the maximum heart rate, as far as is known. If the maximum heart rate is determined experimentally, the muscle mass used plays a major role.

Maximum load

see dedicated article maximum load.


refers to a position close to or (in comparison) closer to the center, i.e. seen laterally in the transverse plane. The conceptual opposite is lateral.

Medial tract

Part of the autochthonous back muscles: interspinal system and transversospinal system.

Median plane / midsagittal plane

The sagittal plane that divides the body into a left and a right half, running exactly in the middle of the body.


The space between the lungs is known as the mediastinum. It is bounded dorsally by the thoracic spine and its longitudinal anterior ligament, and ventrally by the sternum, both of which provide bony protection. Further up in the mediastinum is located : the thymus, the large vessels close to the heart (aortic arch and its branches, pulmonary trunk, superior vena cava), trachea, esophagus, lymph nodes (mediastinal lymph nodes, tracheobronchial lymph nodes), thoracic duct, phrenic nerve, vagus vagus nerve and the recurrent laryngeal nerve, and further down: esophagus, aorta, inferior vena cava, azygos vein, hemiazygos vein, thoracic duct and vagus nerve.


Disc-shaped but non-circular continuous („meniscus“ means „little monk“) cartilage that has a buffering effect in a joint. In the case of the knee joints, the menisci are divided into three zones, of which the inner meniscus is not supplied with blood and therefore degenerates more easily and the outer meniscus is less susceptible due to its blood supply. In addition to degeneration due to excessive wear or lack of exercise, traumatic meniscus tears are not uncommon. See also the in the pathology section: meniscus damage. The task of the menisci of the knee joint is to keep some of the force with which the femur rests on the tibia of the lower limb away from the cartilage coverings of the bone ends, i.e. to relieve them. Other menisci are located in the acromioclavicular joint or the ulnar wrist, for example.

Meniscus root

The ligamentous anchorage of the menisci. Normally, there is a posterior and anterior root for each meniscus of the knee joint, i.e. four for the outer and inner meniscus together per knee joint. If a meniscus root tears, the meniscus can largely move freely in the knee joint, which leads to bumping against the joint capsule, trapping and, above all, a high probability of osteoarthritis/arthrosis in the long term, which is why meniscus root tears usually have to be treated arthroscopically. For more information, see pathology: meniscus damage.


The two (proximal and distal) areas of the shaft of a long bone in which no bone marrow is yet present.

Metatarsal head

Metatarsal heads are the distal ends of the metatarsal bones. The proximal ends are called the base.

Mikulicz line

The Mikulicz line is the line of support of the lower limb from the middle of the femoral head to the middle of the upper ankle joint. Physiologically, it runs through the middle of the knee joint, where a deviation of just over 2 cm is permitted; ideally, the external angle of the knee joint in the frontal plane is 174°. If the Mikulicz line runs further laterally through the knee joint or laterally past the knee joint, a knock-knee is present; if it runs further medially through the knee joint or medially past the knee joint, a bow-leg is present.


The section of the foot around the metatarsal bones, i.e. between the tarsal bones and the toes.

Midfoot running

Compromise between rearfoot running and forefoot running.

Middle hand

The section of the handaround the metacarpal bones, i.e. between the carpal bones and the fingers.

Metacarpal bone / Metacarpalia

the bones between the carpal bones and the fingers. One metacarpal bone belongs to each ray.


the effect of a force acting on a point of a rotatable body, e.g. as a tilting moment or torque


The single-jointedness of a muscle, i.e. the property of a muscle to span exactly one joint and cause a movement in this joint. In general, a muscle or tendon of the musculoskeletal system causes flexion of the joint on the inside of which it runs.


A mathematical term that states that a function (with a one-dimensional, ordered range of values) never decreases (monotonically increasing) or never increases (monotonically decreasing). If it is also impossible for sections to remain constant, this is referred to as strict monotonicity. If, for example, the position of the heel (to be precise, one of the processes of the calcaneus) in the transition from the downface dog to the upface dog or vice versa is represented as a function of the distance to the wall, this should ideally be strictly monotonic. In contrast, in this transition the shoulder position (determined by the center of rotation of the glenohumeral joint, for example) cannot be a monotonic function in sufficiently mobile people, as the distance from shoulder to heel is greater than in both positions when the hip joint is extended.

Muscle failure

There are three kinds and phases of muscle failure, which typically occur one after the other during prolonged intensive exercise and can therefore be assessed against each other.

  1. Concentric muscle failure
  2. Isometric muscle failure
  3. Eccentric muscle failure

The three stages of muscle failure can be easily explained with the following simple experiment, which provokes the stages of muscle failure one after the other: lift a weight in the order of 80-90% of „maximum strength“, for example in the sense of a biceps curl, again and again for as long as possible. At some point, the energy reserves stored in the muscle will be too low to lift the weight again. The fuel supplied via the bloodstream cannot cover the energy requirement needed for this weight in real time anyway, so the barbell visibly stops „halfway“. The phenomenon observed is concentric muscle failure. If you now try to hold the weight in this position, you will notice that this is no longer possible at some point, which is when isometric muscle failure occurs. The attempt to lower the weight as slowly as you like will also come to an unwanted end due to increasing exhaustion, and eccentric muscle failure will eventually occur: the inability to lower the weight in a controlled manner with eccentric muscle contraction. The reason for this behavior naturally lies in muscle physiology: even holding an object against gravity requires constant muscle work of alternating fiber bundles and thus consumes energy. So, unlike in technical systems, there is no mechanism by which the muscle „locks in“, so to speak, so that holding it no longer requires any further energy. In the sense that muscle failure represents a supply that is no longer possible in real time, it has a kind of analogy with the aerobic threshold, at which oxygen can no longer be absorbed in line with consumption. The above experiment also shows that a concentrically achievable force is less than the isometrically achievable force and this in turn is less than an eccentric force, whereby the greater the concentric or eccentric contraction speed, the greater the difference between the achievable forces and the isometric forces.

Muscle injuries

see the dedicated article muscle injuries.

Muscle performance

The physical performance of a muscle. The maximum muscle performance (power) is usually of interest, which is why this is often meant when talking about muscle performance. Since power in the physical sense is the quotient of work (force * distance) and time, halving the time in which a weight is lifted, for example, results in twice the power required. This is therefore a hyperbolic dependency with a singularity. On the other hand, a greater weight can be lifted in a greater amount of time. This process finds its natural limit at the maximum tendon force that a muscle can generate and its conversion according to the lever ratios and the relation of the movement to the direction of gravity according to the sine function. The extreme values of this dependency lie on the one hand, for example, in flexing the elbow joint at any speed without external weight (utilization of maximum power in terms of speed), so that the muscles can only work against the inertia and gravity of the arm itself (other factors such as air resistance or internal tension of tissues, including antagonistic muscles should be neglected here) and, on the other hand, in heavy movements that are performed firstly concentrically at minimum (fixed) speed (F1), secondly statically held isometrically (F2) or thirdly eccentrically at a defined speed (F3), whereby the forces that can be exerted can be estimated against each other so that F1 is less than F2 and this in turn is less than F3. The isometric case does not fit into the classical understanding of work, as no mass is moved in any way. Nevertheless, the muscle with its constantly alternating bundles of fibers „constantly“ applies the force to hold the weight. In addition to these considerations, it must be noted that the maximum force that a muscle can develop depends on the current sarcomere length (see the force-length function). Therefore, strictly speaking, the sarcomere length or the interval of sarcomere lengths (or joint angles) at which the power is measured must be specified when measuring the power. A third type of performance requirement can be identified as the maximum number of repetitions that a muscle can perform at a significantly submaximal effort, as is the case with running, for example, whereby the influence of factors external to the muscle, such as breathing, oxygen transport, quality of the air we breathe (think of higher altitudes), storage capacity for various substances and the current level of the stores, become significantly more influential. The more a performance requirement shifts towards „endurance performance“, the more the factors external to the muscles become important. In extreme cases such as multi-day races, for example the Self-Transcendence 3100 Mile Race, the body’s metabolic performance, and here, mainly the intestins, plays a greater role than classic muscle performance. After all, this race consumes around 10,000 kcal a day over more than 40 days, so that the highest possible number of calories must be consumed and utilized every day.

In practice, the performance of a muscle is not constant over a training session, but decreases noticeably and measurably towards the end of a training session if it only has a certain minimum intensity. On the other hand, the performance achieved over a certain period of time is directly proportional to the energy used. So if, in a model example, you try to reach a speed of 100 km/h as quickly as possible in a car, you can be sure that you have used the maximum amount of energy, i.e. the maximum amount of fuel. In this example, further resistance must be continuously overcome for driving, mainly rolling and air resistance. Extremely slow acceleration does not result in optimum fuel consumption either (minimum energy input), as the integral over the other resistances exceeds any energy input for acceleration over time. There is therefore a certain constant but moderate acceleration behavior which is energy-optimal. For the weight to be lifted in the example above, this means that the weight that can (just barely) be held is greater than any weight that can still be actively lifted, but also that an arbitrarily slow lift also does not lead to optimal behavior, but rather fatigues the muscle by exhausting its local energy reserves to such an extent that muscle failure occurs.

Muscle performance

The maximum physical power (muscle performance) that a muscle can produce. This value depends significantly on the time over which the power is to be produced.

Muscle spindle

Proprioceptors with differential (measure the change in length) and proportional (measure the length) properties, which report the state of stretching of the muscles to the CNS. Ultimately, the elongation state is generally equivalent to the sarcomere length. If the muscle is stretched quickly, a muscle stretch reflex (an intrinsic reflex) is triggered, which sends a contraction stimulus to the same muscle via the alpha-motoneuron. Renshaw cells limit this stimulus by means of negative feedback, so that a very strong innervation is attenuated and good fine motor skills can be imparted, especially to the hands and feet, which are located far distally. One of the best-known examples is probably the patellar tendon reflex.

(muscular) imbalance

Imbalance in the tone, strength or flexibility of the muscles that cover a joint. The agonist-antagonist ratio – which also refers to one or more dimensions of movement – or side disrepancies play a role here. This can be caused by incorrect posture, incorrect loading, one-sided training, one-sided activities, poor technique, injuries or insufficient regeneration, as well as a lack of exercise. This can result in painful muscle tension, overloading of tendons and damage to the joint, especially the cartilage. If incorrect posture is accompanied by an end-degree position, such as a pelvis tilted effortlessly in maximum extension or a hyperextended knee or elbow joints, it can alter ligaments, fascia, capsules and cartilage. The imbalance is not a disease in itself, but it can become pathogenic from a certain degree. Most people have some form of imbalance to a greater or lesser extent, but these can often remain asymptomatic for a long time or remain completely asymptomatic. Common examples of muscular imbalances include

  1. Shortened hip flexors leading to a hollow back, overtensioning of the autochthonous back muscles of the lumbar spine, weakness of the abdominal muscles and hip extensors
  2. Rounded back (in direction of a hunch), caused by poor posture or shortened pectoral and abdominal muscles (pectoralis major), for example
  3. Head forward posture, which overstrains the neck muscles and causes the cervical spine flexors to slacken
  4. Overtension of the protractors and weakness of the retractors of the shoulder blades
  5. Partially elevated shoulder blades resulting in weak depressors and hypertonus of the trapezius and levator scapulae in particular
  6. Sitting with a leaning back and a lumbar spine kyphosis, which weakens the autochthonous muscles and puts them under excessive tension, at the same time weakening the hip flexors and hip extensors.
  7. Imbalance of the internal rotators and external rotators of the shoulder joint due to activities at the computer, working in an internally rotated position as well as throwing activities
  8. Imbalances in all parts of the spine resulting from sleeping positions such as side sleeping and stomach sleeping, especially when the extremities legs or arms are positioned asymmetrically.
  9. Imbalances resulting from sitting with one thigh crossed on top of the other or frequent sitting cross-legged or in lotus position for long periods, especially with favoring one leg
  10. Weaknesses in the abductors of the hip joint, which become visible through Trendelenburg or Duchenne signs
  11. Imbalances by poor posture due to somatizing

As a rule, imbalances are not detectable with imaging techniques, but rather with electromyography (EMG). In addition to the anamnesis, functional diagnostics are the most important diagnostic tool. One of the typical pathomechanisms is that muscles that have postural tasks (muscles with a more tonic function, often more profound) are overloaded by a poor posture, whereupon other muscles step in that have more moving (phasic, usually more superficial) than holding tasks. However, these will tire all the more quickly and react by shortening and hardening. It must be assumed that they break down serial sarcomeres under these conditions. In principle, the more the body is challenged, whether in sport, leisure or at work, the greater the effect of imbalances. They then have the effect of reducing performance, disturbing well-being, delaying regeneration and increasing susceptibility to injury. Quite a few of the imbalances are also likely to result from activities in these areas of life. The increased tone and tension of a muscle can reduce blood flow (see the extreme case of compartment syndrome) and thus cause pain. This pain can lead to further deterioration, possibly in other muscles, through avoidance behavior. This vicious circle must be broken by training. Put into a simple formula of cause and result:

  1. Increased demand results in hypertrophy, increase in strength and tone (depending on sarcomere length under stress)
  2. Reduced demand results in dystrophy and loss of strength, often also of flexibility
  3. Overload results in hypertrophy with a tendency to tension

In the case of imbalances, it is always necessary to think beyond the affected area, and in terms of muscle chains and the effect of gravity, other affected areas must also be examined.

Musculoskeletal system / locomotor system

The locomotor system or musculoskeletal system is the part of the body that keeps it in shape and enables targeted changes to this shape, for example for the purpose of locomotion or voluntary actions. The musculoskeletal system is divided into an active musculoskeletal system and a passive musculoskeletal system:

– Active musculoskeletal system

The active musculoskeletal system includes the skeletal muscles together with their tendons and tendon sheaths, their connective tissue covering (fasciae around muscle fibers, muscle fiber bundles and heads), and the bursae, which protect muscles or their tendons against hard pressure, for example from bones.

– Passive musculoskeletal system

The passive part of the musculoskeletal system, also known as the supporting/bracing apparatus, consists of the bones with their cartilage coverings and connecting cartilage and the joints with their various parts, which, in addition to the bones involved, are primarily the ligaments, intervertebral discs (where present) and joint capsules, as well as the synovia formed by the innermost layer of the capsule.


This circumscribed hardening of a muscle is considered to be the result of overuse or incorrect strain as well as stress. It is a fixation that appears histologically as a waxy degeneration. On palpation, myogelosis is characterized by hardened nodules and tenderness. The shoulders/neck and back are most frequently affected. Myogelosis is regarded as the palpatory equivalent of trigger points, where the pain on palpation is the main symptom. Some authors equate myogelosis with muscle hardening, others differentiate in such a way that myogelosis is circumscribed in small volumes and muscle hardening affects the entire muscle. A further distinction is that muscle hardening reacts to stretching and local anaesthetics, whereas myogelosis does not.


A myotome is the set of all muscles supplied by a spinal nerve.


N. vagus

The vagus nerve an antagonist to the sympathetic nervous system and the most important part of the parasympathetic nervous system. It is the 10th cranial nerve and is the only one that moves from the head into the trunk, hence its name translated as „wandering“. Among other things, it controls digestion and calms the heart, see the effects of the parasympathetic nervous system and heart rate variability (HRV).

Night pain

Night pain means pain that only occurs at night. It is usually joint pain caused by arthritis, osteoarthitis/arthrosis and rheumatic diseases, especially rheumatoid arthritis. Generally, this type of night pain often also occurs during the day when resting for long enough. During pregnancy, night pain also occurs from time to time, mainly due to fluid accumulation in the lymph vessels of the extremities, especially the legs. Several liters of fluid can be stored, which leads to tension pain and tenderness in the support area.

Narrrowuse syndrome

Narrowuse syndrome refers to all disorders that result from the limited use of the musculoskeletal system. To give an example: an office worker who has a sedentary computer-equipped job, where he walks to the printer and the coffee machine about once in the morning and once in the afternoon, each time standing in an adjoining room on the same floor, and who also doesn’t make himself comfortable on the couch every other afternoon or so, but goes for a long ride on his racing bike, is certainly performing well in terms of cardiopulmonary prevention with his sporting activity. In addition, the strength of the lower extremities should be ensured in some important main functions. However, his range of movement is very limited and he only uses many joints in a very narrow ROM, some of them very frequently under load. It is to be expected – and practice regularly confirms this – that his flexibility will decrease both in the joints that he uses only a little and when he does, then in a small ROM, and in the joints that he uses very frequently but with a not too large ROM.

He misses frontal abduction and lateral abduction in the shoulder joint, also exorotation and abduction in the hip joint. This is also predominantly in clear flexion, which should at least significantly shorten the short head of the biceps femoris. Given the work performed by the hamstrings, the frequently iterated medium range movements in the knee joint also contribute to its significant movement. The rectus femoris is well below medium sarcomere length both in occupational and even more so in athletic activity, so that it is also likely to shorten significantly consiodering its power development when cycling. The same naturally applies to the iliopsoas. In general, extension is underrepresented in his flexion-oriented lifestyle, both in the hip joints and in the spine. The elbow and knee joints are also rarely extended. His cervical spine can be in hyperlordosis if he sits poorly, just as it typically is when riding a racing bike. The thoracic spine will also often be in kyphosis, assuming poor sitting behavior, and it certainly is when riding a racing bike. Extensions in many joints will therefore be difficult for him. The expected progressive contractures will sooner or later becomd incomfortable and, in time, disorders will manifest.

If fitness in its classic definition is seen as a product of the basic components of endurance, strength, flexibility, coordination and speed, then the test person will not find himself at the top of the list of fitness athletes, as the discipline of flexibility significantly depresses the product. He will not score particularly well (achieve a good factor) in „speed“ either, as admittedly the muscular performance of some of the muscles of the lower extremities and the associated hip joint muscles is not bad and therefore a minimum level of speed must also be present. However, due to his limited flexibility, he will have a rather low ROM and will therefore not gain much swing in real speed exercises such as throwing movements and jumping movements to get to the front of the field. After all, the kinetic energy (whether of the thrown object or the accelerated limb) can be described as an integral of the force developed over the radian measure.

Nerve compression syndrome

Syndrome with pain, sensitivity disorders such as numbness, tingling, reduced sensation and innervation disorders caused by pressure on a nerve. This can be a spinal nerve that has just emerged from the spinal cord, as in the case of an intervertebral disc, in which case it is referred to as nerve root compression syndrome or radiculopathy (lat. „radix“: root) or a nerve located further in the periphery, for example when tendons swell in the area of a physiological constriction between bones and press on a nerve, as is the case with cubital tunnel syndrome (affected: ulnar nerve), tarsal tunnel syndrome (affected: tibial nerve) and carpal tunnel syndrome (affected: median nerve). In the latter case it is called nerve compressions syndrome, a nerval form of an entrapment syndrome. Another common nerve compression syndrome is Morton’s neuroma, which usually occurs in the context of splayfoot and causes metatarsalgia.

Nerve root

Nerve roots are the segmental parts of the spinal nerves that join together and emerge from the spinal cord. Pressure on these can lead to a nerve root compression syndrome and, in more distal locations, to a nerve compression syndrome.

Nerve root compression syndrome

A nerve root compression syndrome is a nerve compression syndrome caused by pressure on a spinal nerve exiting the spinal column. See there for description.


Complaints ands symptoms that are triggered by a nerve root compression syndrome of one or more nerve roots emerging from the spinal column, briefly referred to as radicular, see also the explanations there.

Neutral zero

Upright posture in which the feet are parallel and closed, the knees are extended, the pelvis is upright, the upper body including the cervical spine is straight and the arms rest against the body in such a way that the inner elbows and palms – in contrast to standard anatomical position – point towards the body. Neutral-zero corresponds to tadasana and must not be confused with the very similar standard anatomical position.

NRS (Numeric Rating Scale / Numeric Analog Scale)

The method of assessing intensities or other quantities (quantifiable variables) with numbers, usually from 0 to 10, is usually referred to as Numeric Rating Scale (NRS). This method is mostly used to query pain intensities. Here, 0 stands for „no perceptible pain sensation at all“ and 10 for the maximum imaginable pain. Multiplied by the number 10, percentages can then be obtained. The NRS is usually used to measure current pain, but it can also be used to measure average pain over a period of time. In principle, the NRS is also suitable for completely different uses than pain intensity.

Nutation / contranutation

The movement of the SIJ (sacroiliac joints) around a horizontal transverse line of approx. maximum 4 degree.


oblique abdominal muscles

the oblique abdominal muscles: Mm. obliqui externi abdomini and Mm. obliqui interni abdomini, which are crossed at a large angle and contribute to the rotation of the trunk, lateral flexion and flexion in the lumbar spine and lower thoracic spine. With regard to rotation, they are partly synergists and partly antagonists to the corresponding muscles of the oblique system of the autochthonous back muscles, and antagonists with regard to their extensor effect. The oblique abdominal muscles belong to the expiratory auxiliary respiratory muscles.


Breathing restrictions are called obstructive if they result from a narrowing of the bronchial airways. The most important obstructive lung diseases are COPD, bronchial asthma and chronic obstructive bronchitis. The causes are usually secretions, foreign bodies or tumors in the airways. In addition to imaging and endoscopic procedures, obstruction can be diagnosed using the Tiffeneau test.

1RM (Einwiederholungsmaximum)

The 1RM or one-repetition maximum is the maximum weight that can be achieved in a specific exercise in a single, cleanly performed repetition after an adequate warm-up. These are usually exercises such as bench presses, neck presses, rowing, lat pulldowns, deadlifts or squats. As these exercises invariably involve several muscles that work together synergistically or in a kinetic chain, the 1RM only represents the maximum repetition of the individual muscles in terms of their tendon force, which is much more difficult to determine. If it is not possible to determine the 1RM, for example because a correspondingly high resistance cannot be achieved with an adjustable grip strength trainer or a training device does not provide a correspondingly high weight capacity, the 1RM can be approximated from a different, not too large number of repetitions using the following table, which shows the assignment of the number of repetitions to the percentage of 1RM.

  • 1: 100%
  • 2: 95%
  • 3: 92%
  • 4: 89%
  • 5: 86%
  • 6: 84%
  • 7: 81%
  • 8: 79%
  • 9: 76%
  • 10: 74%
  • 11: 71%
  • 12: 68%


Opposing the thumb to the hand, enables objects to be gripped. The little finger is also capable of opposition to a small degree.


Non-invasive orthopaedic aid attached externally to the body with the purpose of providing support, restricting movement or relieving pressure on tissue or joints. This includes all types of splints, support devices, girdles and corsets. Orthoses can be complex and made of several materials. Bandages are not usually included. The orthosis is therefore a – usually passive – piece of exoskeleton attached to the body from the outside.


Chipped bone particles or very small bones.


Sclerosis of the subchondral area of the vertebral bodies occurring as a result of chondrosis.


Increase in bone mass, usually in the context of osteoarthritis/arthrosis from grade 2 at least. The osteoarthritic cartilage alteration leads to incongruence of the joint surfaces and local increases in pressure, resulting in subchondral sclerosis and, above this, local cartilage and bone necrosis (debris cysts). This material accumulates at the edge of the joint surfaces and calcifies to form osteophytes, which literally translated means „bone-plants“. They can be detected by ultrasound and X-ray and are considered a sign of advanced osteoarthritis/arthrosis. They can cause consequential damage through local pressure on nerves or other soft tissue (tendons, ligaments). If they break off, they can also lead to further disorders as free joint bodies, e.g. to impingement.

Outward rotation / external rotation (shoulder blade)

Movement of the scapula in the plane in which it mainly extends, with the inferior angulus (lower tip) pointing outwards and upwards, which is a prerequisite for raising the arm above 90°. These muscles rotate the shoulder blade outwards. In the yogabook, for the shoulder blade the term outward rotation is preferred to easily distinguish this movement of the shoulder blade from that of the external rotation of the humerus in the glenohumeral joint.

Outward rotators / external rotators (shoulder blade)

Muscles that turn the shoulder blade outwards at the bottom, i.e. into outward rotation:

  1. Trapezius
  2. Serratus anterior


The foot is placed beyond the median line on the contralateral side of the body. This can be caused by:

  1. Muscular imbalance, particularly weaknesses in the hip muscles, especially the abductors, hypertension of the adductors
  2. Functional leg length discrepancies: predispose to overcrossing, especially of the longer leg

Overcrossing leads to overpronation, ITBS (runner’s knee), shin splints and knee pain.

Overhand grip

The overhand grip refers to gripping an object, often a piece of sports equipment such as a dumbbell, with the back of the hand facing upwards and the object or its handle gripped from above by the palm of the hand. In contrast to the underhand grip, all muscles with a dorsiflexor effect in the wrist, i.e. the finger extensors and the pure dorsiflexors of the wrist, are required in addition to the finger flexors, which have to secure the grip. In contrast to the underhand grip, the forearm is in pronation here and the arm biceps can work less well, so that the brachialis provides a higher proportion of the force exerted and the maximum force that can be achieved is lower.

Overpronation / Hyperpronation

see hyperpronation.


Placing the foot too far in front of the body. Overstriding slows you down and leads to rearfoot running with a loss of efficiency and additional strain on the joints, especially the ankle joints, as well as overloading the tendons of the pronator fibularis longus and fibularis brevis and PFPS (jumpers knee, patellar tendinopathy). Weakness of the gluteus maximus is often a contributing cause.

Oversupination / hypersupination

see hypersupination.


Overtraining describes the effect of a chronic overload reaction that occurs when frequent training is carried out without sufficient regeneration and is characterized by the following possible symptoms:

  • decreasing (instead of increasing) performance,
  • Possible loss of motivation or concentration,
  • Increase in susceptibility to injury and infection,
  • Increased resting and working heart rate or exercise heart rate,
  • Headache
  • Sleep disorders
  • Triggering depression

If some of these symptoms are identified and overtraining is assumed to be the cause, this has the status of a disease.
There are various hypotheses as to the causes of the somatic and physiological disorder: cause-related, clinic-related and pathophysiological. If overtraining is detected, a break from exercise is obligatory, and sports medical supervision may be necessary. Doping or medication abuse is by no means an appropriate way of dealing with the disorder. In severe cases, therapy can be lengthy and difficult. It is best to be alert to the possibility of overtraining when organizing training. A decrease in heart rate variability HRV can be seen as a rather early indicator. With further overtraining, the resting heart rate RHR would then also increase.


Overuse means overloading and refers to a load that exceeds the load-bearing capacity of a structure. The causative factors and the affected structures can be diverse. The bradytrophic tissues are frequently affected by overuse syndrome: tendons (tendinitis, tendinosis, tendinopathy) and their tendon sheaths (tendovaginitis, together with tendinitis also known as tendosynovitis), ligaments, capsules, cartilage, bones and the bursae that cover the muscles or their tendons (bursitis). Cartilage with a turn over beyond the lifespan is frequently affected by overuse. One of the most common examples, apart from the all too familiar meniscus of the knee, is the disc in the ACG joint (acromioclavicular joint). These are often already massively damaged by arthritis in the fourth decade of life and are often no longer detectable in the fifth decade of life. The muscle itself can also get into a position in which it can no longer withstand the strain, in which case it reacts with a tendency to spasm, strain, hypertonus, loss of performance, overuse, for example. As the muscle is designed for rapid, extensive metabolism, it is less affected. Overuse can occur in sport, but also in non-sporting professional activities, e.g. as RSI syndrome in secretaries or as golfer’s elbow in road workers who frequently work with a shovel. In sport, overuse is often associated with inadequate increases in performance or inadequate performance requirements for the level of training. Those who take up sports training (for the first time) are usually confronted with the necessity that various parts of their body, not only their musculoskeletal system, do not adapt to the required performance or strength demands quickly enough. The body adapts most quickly to strength and cardiopulmonary endurance demands. The bradytrophic tissues of the musculoskeletal system adapt with a significant delay due to their sometimes far greater turn over (renewal time), so that, depending on the demand, they cannot provide adequate resilience to the increased performance. They are then unable to regenerate sufficiently from one demand to the next and adapt even less, so that degeneration symptoms are often the result.


Pain at rest / rest pain

Pain that occurs (also or only) at rest without active or passive movement and without strain. Parts of the body that are painful at rest are usually also painful during movement. Pain at rest often occurs in the musculoskeletal system with osteoarthritis/arthrosis, arthritis, insertional tendinopathies, fractures, nerve entrapment syndromes (carpal tunnel syndrome, cubilar tunnel syndrome, tarsal tunnel syndrome), cervical spine syndrome. Other types of pain at rest are ischemic, cardiovascular and neurological pain at rest. It can be of different qualities, such as tension pain (inflammation) or drilling pain (bone damage).

Pain in motion

Pain that occurs during active or passive movement without being subjected to body weight or an external weight. Movement pain can be divided into active pain (the movement is performed by the person being examined) and passive pain (the movement is performed by an examiner). Movement pain is typical for specific parts of the musculoskeletal system such as muscles and joints. The back, shoulder joint and knee joint are frequently affected. The causes of movement pain can be varied: degenerative diseases of the musculoskeletal system, fractures, ruptures, fibromyalgia, polyneuropathy, various diseases of the spine or inflammation.

Pain quality

Pain is differentiated according to sensory and affective qualities. Sensory qualities include „burning“, „pressing“, „drilling“, „stabbing“, whipping“, „pulling“, „knocking/pounding“, „shooting“, „sharp“. Affector qualities are, for example, „torturing“, „violent“, „devastating“, „paralyzing“. In addition, subjective pain qualities such as „subliminal“, „dull“ or „bright“ can be specified verbally.

Painfulness in motion

The ability of a part of the musculoskeletal system (rarely: internal organs) to cause pain on movement through active or passive movement, even without load.

Palmar aponeurosis

The aponeurosis palmaris is the tendon plate of the palm and consists of multiple longitudinal and transverse fibers in different layers. A final layer of connective tissue lies above this. Depending on the author, only the latter or the whole is referred to as palmar fascia. Laterally, the palmar aponeurosis merges into the fascia of the thenar and hypothenar muscles.

Palmar fascia

The aponeurosis palmaris is the tendon plate of the palm and consists of multiple longitudinal and transverse fibers in different layers with a superficial connective tissue layer. Some authors refer exclusively to this as the palmar fascia, but do not include the aponeurosis.

Palmar flexion / palmar flexion (hand)

Increase in the dorsal (back of the hand) angle of the hand to the forearm at the wrist, i.e. movement of the palm of the hand towards the forearm, i.e. the back of the hand away from the forearm.

Palmar flexors

Group of muscles that perform palmar flexion, i.e. bring the palm of the hand closer to the forearm

Palmare plate

Synonym for the palmar ligament, which covers each metacarpophalangeal joint and the interphalangeal joints on the palmar side and protects against hyperextension.


One of the methods of physical examination: palpation using the examiner’s sense of touch. In the simplest case, this can be a test for tenderness or a test for irregularities in a tissue that can be palpated superficially. For example, a ganglion, swelling or myogelosis can be palpated. Muscle ruptures or tendon tears can also be palpated well in some cases. The degree of muscle tension (tone/tonus) can be determined by palpation, both the resting tone and the tension of a muscle used or to be used in a pose. For example, the tension of the arm biceps can be palpated in the free sitting twist to determine whether it is working and roughly how intensively it is working as frontal abductor of the shoulder joint to push the ipsilateral shoulder area backwards and thus promote rotation of the spine and as the elbow flexor to pull down the shoulder area due to the hand as a punctum fixum and thus depress the shoulder blade and contribute to equalizing the height of both shoulders in the pose. If the examiner wants to palpate the tension of a muscle in order to deduce how intensively a muscle is working, he must relate the tension felt, i.e. the resistance to the palpator’s pressure, to the resting tone palpated. Only from the delta an approximate assessment of the work of the muscle can be made. However, it is not possible to draw any conclusions about the exact tendon strength of the muscle. Other examples of the use of palpation include palpation of the course of the tendons of the biceps in the corresponding exploration and of the tissue tone of the gastrocnemius in supta virasana / virasana to determine whether a reported pain is due to tissue compression. Palpation is also used to assess the tone of the quadriceps in uttanasana or to assess the tone of the trapezius when performers complain of increased tension or a tendency to cramp. The joint line tenderness test also falls under palpation, although the results are clearer when pressure is applied to the joint space with the fingernail rather than a comparable sensitive fingertip. Palpation can also detect thermal changes such as inflammation.

Parasympathetic tone

State of increased excitation of the parasympathetic nervous system.

Parasympathetic nervous system

The parasympathetic nervous system is the part of the autonomic nervous system that is responsible for regeneration and building up energy reserves and is therefore largely the opposite of the ergotropic sympathetic nervous system, which controls the increase in performance and mobilization of energy reserves. These effects of the sympathetic nervous system are referred to as ergotropic. It is therefore largely antagonistic to the parasympathetic nervous system. The nerve fibers of the parasympathetic nervous system include some of the cranial nerves III (oculomotor nerve), VII (facial nerve), IX (glossopharyngeal nerve) and especially X (vagus nerve). The trigeminal nerve also carries sections of parasympathetic fibers, but these originate from the facial nerve. The parasympathetic nervous system has a negative chronotropic and negative dromotropic effect on the heart (promoting excitation conduction), has a vasodilatory effect on the vessels in the genital area, is constrictive and promotes mucus secretion in the bronchi, increases secretion and peristalsis in the digestive tract, promotes micturition in the genitourinary system, promotes contraction of the uterus, promotes miosis (pupil constriction) and accommodation and promotes saliva production. Increased excitation of the parasympathetic nervous system is referred to as parasympathetic tone or usually as vagal tone and has an HRV-enhancing effect.

Partial body weight

the weight that is supported and is not itself part of the supporting body parts (usually extremities). In the example of handstand, this is the total body weight minus that of both arms, in the case of ardha chandrasana the total body weight minus that of the standing leg. The partial body weight is an important factor in the moments that occur in the supporting extremity or extremities or their joints, but ultimately their amount also depends on the lever arm (distance from the center of rotation of the joint to the center of gravity of the partial body) and the sine of the angle to the direction of gravity.

Passive insufficiency

State of a muscle not being fully contracted, that is, not being actively insufficient, i.e. actin and myosin filaments have not fully interlocked, but being prevented from further contraction by a lack of flexibility of its (more precisely: one of its partial) antagonists. The occurrence of passive insufficiency is pathological in monoarticular muscles and physiological in biarticular and polyarticular muscles.

Patellar dyskinesia

Patellar dyskinesia is the term used to describe incorrect movement of the patella in the femoropatellar sliding bearing. There are several possible reasons for this, such as unfavorable traction ratios of the quadriceps parts, usually too little traction of the vastus medialis or excessive traction of the rectus femoris or vastus lateralis. Incorrect movement of the patella can also occur during movement sequences, for example when in running, towards the end of the standing leg phase, i.e. when pushing off, the lower leg is turned out in the knee joint. The same applies if the lower leg rotates outwards in the knee joint during wide forward swing of the leg. In the first case, the biceps femoris may be disproportionately strong or under disproportionate strong tone compared to the inner hamstrings or the latter may be too weak; in the second case, the flexibility of the biceps femoris may be too low in relation to the inner hamstrings. Malformations of the patella, in particular a fin that is too weak, or a tibial tuberosity that is located too far laterally can also lead to patellar dyskinesia.

Patellar luxation

Dislocation of the patella. Patellar dislocations are painful and usually occur when the knee joint is largely or fully extended, usually the patella dislocates laterally. There are a number of reasons for this. As part of the physiological final rotation, the lower leg is turned out in the knee joint, which pulls the patellar ligament slightly laterally. In addition, the contact pressure of the patella in extension or hyperextension of the knee joint is minimal and the guidance of the dorsal fin of the patella in the intercondylar sulcus decreases with increasing extension of the knee joint. As a result, the intercondylar sulcus bends slightly laterally in the cranial region. If due to muscular imbalance (weakness of the inner hamstrings or the popliteus) the internally rotating torque is too low (regarding the externally rotated position in final rotation), the lateralization tendency of the patella is also increased. In cases with a tendency to patellar dislocation, the quadriceps as a whole, but especially the medial vastus and the inner hamstrings should be trained to reduce the tendency to dislocatate laterally, provided there is no other regional disorder. The vastus medialis can be very important here, as its caudal part (also known as the „vastus medialis obliquus„) runs obliquely to transversely and is primarily responsible for centering the patella. It is equipped with corresponding fiber types and receptors for this purpose. A knock-knee also leads to unphysiological guidance and incorrect traction on the patella, as it is pulled laterally. A laterally pulled patella regularly leads to an increased load on the lateral half of the femoropatellar sliding bearing and thus also on the lateral half of the retropatellar cartilage, which can lead to patellofemoral pain syndrom/chondropathia patellae (PFPS) and later to retropatellar arthrosis.


The pelvis is generally understood to be the space occupied by the large pelvis plus the small pelvis. The large pelvis can be seen as part of the abdominal cavity, as some important organs of the abdominal cavity extend seamlessly into the large pelvis.

– Pelvis, small

The lesser pelvis is the lower space between the iliac blades (ala ossis ilii) of the ilium, which is bounded cranially by the linea terminalis. This space contains, among other things, the urinary bladder, rectum and, in females, the uterus, ovaries, vagina and, in males, the prostate.

– Pelvis, large

The large pelvis is the upper space between the iliac blades (Ala ossis ilii) of the ilium, which borders caudally on the small pelvis and is delimited by the Linea terminalis. This space contains some abdominal organs, e.g. the ileum and the sigmoid.

Pelvis girdle (hip girdle, bony pelvis, pelvis arch)

The pelvic girdle is the bony structure that connects the spine to the lower extremity leg, i.e. the two hip bones and the sacrum between them. In contrast to the dorsally open shoulder girdle, the pelvic girdle is closed, the covered joints are the two ISG dorsally and the pubic symphysis ventrally.

Pelvic torsion

A pelvic torsion is defined by a hip bone tilted forward in standard anatomical position on one side compared to the other side. Typically, this twisting occurs dorsally in the two sacroiliac joints and ventrally in the pubic symphysis, so that the respective degree of nutation is unequal in both. It is often the result of laterally unequal tension of the hip extensors and hip flexors, especially the iliopsoas, rectus femoris as hip flexors and gluteus maximus as the strongest hip extensor, but also the hamstrings, which make a significant contribution to extension, especially at lower flexion angles in the hip joint and with less force exerted for extension.

Among the hip flexors, the iliopsoas is particularly noteworthy, as it is often at the edge of its ROM in standard anatomical position in less mobile people anyway. Pelvic torsion can be recognized on inspection, for example, by a ASIS that protrudes further on one side or a dorsally unevenly high PSIS. It can also be perceived in the supine position (e.g. savasana) by the fact that the two iliac crests are at an unequal distance from the floor. Often, especially when the flexibility of the hip flexors on one side is less than that of the other side, one knee joint flexes more than the other in savasana.

Pelvic obliquity

a pelvis tilted in standard anatomical position to one side in the frontal plane. Both hip joints and both ASIS are then unequal in height, or in other words, the vertical axis of the pelvis is not vertical. This can be caused by (functional or rarely also anatomical) leg length discrepancies, as well as subluxations in the ankle, knee or hip joints. An unequal pull of the adductors and abductors can also lead to pelvic obliquity: in standard anatomical position, the hip joints normally form an isosceles trapezoid with the heels. If one leg is inclined differently to the vertical than the other, it pulls the hip down with it and the pelvis is tilted.

A persistent pelvic obliquity usually causes a scoliosis of corresponding extent, in the full extent later on double S-shaped. The body corrects the static problem caused by a pelvic obliquity and thus a oblique sacrum in such a way that, with optimal compensation, the center of gravity of the large partial body weight above the pelvis runs centrally through the line connecting the two acetabuli.

Pelvic obliquity should not be confused with pelvic torsion, but can also occur together with it.


The area of the upper body delimited by the dorsal anus and genital area ventrally and laterally by the thighs. In standard anatomical position, this is the lowest area of the upper body.


One of the methods of physical examination: tapping on a part or area of the body. Percussion is only of secondary importance in asana. There are hardly any examples of the acoustic evaluation of percussion, as used in medical examinations e.g. of the lungs, but in various tests, such as the Tinel type for carpal tunnel syndrome (see the test), cubital tunnel syndrome (see the test) or tarsal tunnel syndrome (see the test), the affected nerve is percussed several times in order to reproduce known symptoms as a provocation test.

Phalange (phalanx)

Finger or toe phalanx. Like toes 2-5, fingers 2-5 have three phalanges, while the thumb (pollex) and big toe (hallux) each have two.

Physiological kyphosis (thoracic spine)

The kyphotic curvature measurement of a healthy thoracic spine in standard anatomical position or neutral zero.

Physiological lordosis (lumbar spine)

The lordotic curvature measurement of a healthy lumbar spine in standard anatomical position or neutral zero.

Pivot joint / rotary joint / trochoid joint

see under joint shapes

Plane joint

see under joint shapes

Plantar fascia

The aponeurosis plantaris or plantar aponeurosis is a tendon plate between the calcaneus on the one hand and the metatarsophalangeal joints on the other. It is mode superficial that the plantar ligaments such as the plantar long ligament. It covers the metatarsal bones and some tarsal bones. It thus protects the deeper structures (nerves, tendons, blood vessels) and secures the position of the fat pads of the foot. It is partly the insertion for

  1. Abductor hallucis
  2. Flexor digitorum brevis
  3. Abductor digiti minimi

It is important as a passive part of the tension belt to prevent the longitudinal arch of the foot from collapsing and to limit the extension of the foot when unter load.

Plantar flexion (foot)

Increasing the dorsal (back of the foot) angle of the foot to the lower leg. This movement is performed by the plantar flexors, the most important of which is the triceps surae. Synonym: extension of the ankle.

Plantar flexors

All muscles that perform plantar flexion in the ankle joint (more precisely: the ankle joints), i.e. increase the dorsal (back of the foot) angle of the foot to the lower leg. These are M. triceps surae, M. fibularis longus, M. fibularis brevis, M. flexor digitorum longus, M. tibialis posterior, M. plantaris

Plantar plate

The plantar plate is a 2-5 mm thickened capsule (fibrocartilaginous cartilage) under the metatarsophalangeal joints of the toes. Overuse can damage the plantar plate, especially when wearing shoes with little flexibility or walking barefoot on hard floors. High heels also put strain on the plantar plate because they can multiply the load on it. Another risk factor is a long 2nd ray. Cracks in the plantar plate can lead to metatarsalgia. Hammer toes and claw toes can develop later, possibly with dislocation in the metatarsophalangeal joint (MTP) and the development of metatarsophalangeal joint arthrosis/osteoarthritis.


Multi-articularity of a muscle, i.e. the property of a muscle to span more than two joints and cause movement in them

Post-stress-induced pain

If an exertion pain does not subside immediately after the end of the exertion, this is referred to as post-exertion pain, also known colloquially as a „reverberation“ of the pain.


denotes a direction and means „from or to the rear“ and is identical to the term dorsal. The conceptual opposite is anterior, which in turn corresponds to the term frontal or ventral.


see this special article.

Potential energy

The physical energy stored in the height of a body above the gravitational center of the gravitational source (in this case the earth), which begins to decrease when the body is released, as the body accelerates at 9.81 m/s² (in a vacuum) towards the center of the earth. If a body is moved further away from the center of the earth (i.e. upwards), this requires physical work and energy input.


Pressure is force per area. If a person stands with both feet on the ground, the large effective partial body weight causes compression of the tissues under the foot bones, which we perceive as a very moderate level of pressure. If we only stand on the ball of the foot or the heel, the pressure (much smaller area with the same partial body weight) is significantly increased, which the pressoreceptors in the foot report to us as a subjectively higher pressure sensation. If we tried to stand on the extremely small area of a nail tip, the pressure would be so high that the skin would not be able to withstand it and the nail would dig into the foot and possibly even the ligaments between the bones of the foot would not be able to withstand the pressure. We see an important feature of pressure when we leave the realm of solid-state physics: Pascal’s principle. In liquids (at a certain level, i.e. a certain water column above it) and gases (here the level is practically irrelevant), the pressure is the same at every point of the same level and undirected, i.e. „the same in every direction“ at a certain point. This is important, for example, for understanding the sensations conveyed by the pressoreceptors, as well as for understanding the intervertebral discs of the spine and the related pathomechanisms.

Pressure pain / palpation pain

Pain that is triggered by external intervention such as palpation or other mechanical action on a tissue that is painful under pressure (pressure dolence). The sensation of pain is usually dependent on the intensity of the pressure. This pressure can also be caused by clothing or footwear. The pressure pain may subside immediately when the external pressure is stopped or it may „reverberate“ for a short time (post-loading pain). Pressure pain very often indicates inflammation. It must be differentiated conceptually from „tension pain“, which indicates increased tension in a tissue, is also often caused by inflammation, but is not triggered by deliberate external pressure, but is present without any intervention.


Progressive, advancing. Progressive refers to a disease or process that advances in scope or stage.


Progression, advancement, of a disease. There are several reasons for progression, one is simply a negative balance between healing and damage, as is often the case with osteoarthritis/arthrosis, in other cases, regeneration is no longer possible at all, for example in the case of osteoarthritis/arthrosis: the turn over of the damaged cartilage is beyond the lifespan. Diseases that progress are referred to as progressive.

Pronation (foot)

in standard anatomical position, the tilting movement of the foot around its longitudinal axis, which is caused by the lowering of the inner foot in relation to the outer foot

Pronation (forearm)

the „rotation“ of the forearm: turning the radius over the ulna. In standard anatomical position the palm points backwards, i.e. away from the biceps, see below.

Pronation (arm)

the overcrossing movement of the forearm, in which the radius is turned away from its parallel course to the ulna towards crossing it. With the arm extended in front of the boxy turned out in the shoulder joint, this corresponds to a downward-facing palm. Pronation is possible up to approx. 180 with good flexibility from max. supination. With a pronated forearm the palm away from the biceps.

Pronators (foot)

All muscles that pronate the foot in the ankle joint (more precisely, the three ankle joints, each to a different extent), i.e. raise the lateral edge of the foot or lower the medial edge of the foot. These are M. fibularis longus, M. fibularis brevis, M. fibularis tertius, M. extensor digitorum longus.

Pronators (forearm)

All muscles that pronate the forearm, i.e. pronator quadratus, pronator teres, flexor carpi radialis, brachioradialis from a supinated position only and extensor carpi radialis longus (weak when the arm is flexed). See also the elbow joint.


Self-perception of the body independent of external sensors, i.e. the 5 senses. Proprioception makes it possible to perceive the position of the body in space and the position of the individual body parts in relation to each other, as well as the tension of the muscles and the force exerted. A distinction is made between

  • Joint position sense: Sense of the geometric position of the body and joints
  • Sense of movement (kinethesia): continuous sensation of changes in the position of the body or body parts
  • Sense of force and resistance: Sensation of tension and pressure.

The sensors responsible for this are called proprioceptors:

  1. Muscle spindle: fibers arranged in the muscle parallel to the muscle fibers, which record the proportional behavior, i.e. the absolute length of a muscle with static core fibers and the differential behavior, i.e. the change in length, with dynamic core fibers.
  2. Tendon spindle (also: Golgi organ, Golgi tendon receptor): slow-adapting tension sensors located in the transition area between muscle and tendon fibers, basis of proprioceptive reflexes
  3. Sensitive receptors in joint capsule, ligaments, periosteum

In contrast to proprioception, visceroception enables the perception of internal organs. Both together are also referred to as interoception. Various proprioceptors are present for this purpose.

A distinction can be made between conscious proprioception, which is evaluated during conscious and targeted movements such as balancing or yoga poses, and unconscious proprioception, which is sufficient for mechanical movements such as walking or climbing stairs.


The receptors that enable proprioception are:

  • Muscle spindle: fibers arranged in the muscle parallel to the muscle fibers, which record the proportional behavior, i.e. the absolute length of a muscle with static core fibers and the differential behavior, i.e. the change in length, with dynamic core fibers.
  • Tendon spindle (also: Golgi organ, Golgi tendon receptor): slow-adapting tension sensors located in the transition area between muscle and tendon fibers, basis of proprioceptive reflexes
  • Sensitive receptors in joint capsule, ligaments, periosteum

Protraction (shoulder blade)

Movement of the shoulder blade sideways and ventrally, i.e. away from the spine. The muscles performing this movement are the protractors. The opposite movement is called retraction.

Protractors (shoulder blade)

Muscles that move the shoulder blade away from the spine and ventrally, i.e. outwards and forwards, towards the sternum:

  1. Serratus anterior
  2. Pectoralis minor
  3. Pectoralis major


refers to a position in an extremity close to or (in comparison) closer to its attachment to the trunk. The conceptual opposite is

Pseudoradicular pain

Non-specific, localized pain with radiation („referred pain“) in the direction of an extremity similar to a radicular pain symptom, but without its efferent or afferent neurological deficits (in the area of innervation or sensitivity), as the spinal nerve itself is not impaired in its function. Pseudoradicular pain occurs, for example, as a result of facet syndrome, muscular or joint disorders and SI joint blockages.


Pulse refers to the pulse wave in the peripheral blood flow that can be detected by palpation or technical sensors, e.g. the radial pulse on the radial-palmar side of the forearm in front of the wrist or the carotid pulse of the carotid artery ventral-medial of the sternocleidomastoid. If the pulse is lower than the heart rate in a time interval, there is a pulse deficit.

Pulse deficit

see dedicated article pulse deficit.

Pulse Wave Velocity PWV

Measuring the pulse wave velocity is a non-invasive way of determining the stiffness of the arteries, which helps to assess the cariovascular risk. This is determined at two (ideally widely separated) points on a continuous vascular path, usually an extremity, e.g. upper arm (brachial artery) and in front of the wrist (radial artery). The most important disease that increases the pulse wave velocity is Arteriosclerosis. Increases in pulse wave velocity are also seen in the following cases

The pulse wave velocity must not be confused with the lower flow velocity. In a young, healthy aorta, the pulse wave velocity is approx. 4-6 m/s due to the elasticity (wind kettle function) and the larger lumen, and then approx. 8-12 m/s in the periphery, e.g. in the radial artery. In an arteriosclerotically altered aorta, the pulse wave velocity is increased; the elasticity of the aorta also decreases with increasing biological age and consequently increases the pulse wave velocity. Increased pulse wave velocity leads to an increase in systolic blood pressure and a decrease in diastolic blood pressure as a result of increased pulse wave reflection, i.e. an increase in amplitude, an increased workload of the left ventricle and reduced perfusion of the coronaries in diastole. Physiologically and regularly in healthy young people, the second peak in the pulse contour (course of intra-arterial pressure) caused by the pulse wave reflection is lower than the first peak generated directly by the ventricular action (negative augmentation P2 – P1) and shows a clear gap. In addition to the augmentation, the augmentation index, which relates the augmentation to the pulse pressure, is an important parameter. If the vascular elasticity is significantly lower, the second peak moves closer to the first and can exceed it (positive augmentation). The augmentation index increases with age and blood pressure and decreases with height and heart rate. As a result, shorter people have a slightly higher average cariovascular risk than taller people. Various studies have shown an increase in mortality of 10 – 39% with a 1 m/s increase in pulse wave velocity. On average, women have a slightly higher index than men due to their shorter height.

Punctum fixum

The punctum fixum is the part of the body that is fixed during a movement (e.g. standing on the floor). The opposite is the punctum mobile. Which part remains stationary and which part is moved depends on these two. Examples

  1. In uttanasana the legs are punctum fixum with regard to the work of the hip flexors, the pelvis with the upper body is moved.
  2. In parivrtta trikonasana the lower arm is punctum fixum with regard to the lateral adduction and retroversion in the shoulder joint
  3. iI upface dog the arms are punctum fixum in the dog position head up with stretched feet when the frontal adduction in the shoulder joint pulls the upper body and with it the pelvis forward.

The usual anatomical view of the attachment and origin of a muscle suggests that the more central origin is the fixed point from which the attachment is drawn. This assumption, which is often incorrect in sports science, is generalized by considering the moving part punctum mobile and the fixed part punctum fixum, even if this model is not yet general enough, as shown by poses such as navasana, in which the hip flexors bring the thighs and pelvis with the upper body halfway evenly closer together. Another counter-example is the downface dog, in which the deltoids mainly push the shoulder area towards the feet through their frontal abduction in the shoulder joint. Here too, neither the arms nor the upper body can be regarded as a puntum fixum, as the force applied moves both.

Punctum mobile

The relevant counterpart to the punctum fixum, see the derivation of the concept there. A moving part of the body is referred to as a punctum mobile when a muscle connected to it, whose origin or attachment is in the punctum fixum, exerts force on it.



Racket sports (racket sports)

see the dedicated Racketsports page

Radial abduction (hand)

Reduction of the distance and angle of the thumb-side of the hand to the radius.

Radicular pain

Pain caused by irritation (e.g. pressure) of a nerve root, as occurs in nerve root compression syndrome (radiculopathy). This is usually caused by intervertebral disc damage, osteophytes or inflammation. The pain typically projects into the dermatome of a nerve root. Radicular pain requires clarification and often also treatment. The compression of nerves can lead to their atrophy, but also to atrophy of the supplied musculature. The term neuroradicular is also used synonymously. See the difference to pseudoradicular here.

Range of motion ROM

see dedicate page ROM.


The entirety of all phalanges of a finger or toe with its associated metacarpal or metatarsal bone.


see special article regeneration.

Reclination (neck)

Tilting of the head backwards towards the back, the term is synonymous with extension of the cervical spine.

Rectus sheath

The aponeurosis, which envelops the rectus abdominis superficially and profoundly. It emerges laterally from the tendons of the oblique abdominal muscles and the transversus abdominis and forms the linea alba between the two sides of the rectus abdominis. The anterior wall of the rectus sheath (lamina anterior) extends to the pubic bone, but the posterior wall ends at the linea acuata.


Recurrence of disease activity of a chronic relapsing disease.

Rein system

see dedicated article rein system.


Partial abatement or complete cessation of disease activity and the associated symptoms of a chronic disease, without permanent damage that has already been acquired being reversed. Remission is therefore the opposite of relapse and, in the case of chronic progressive diseases, also excludes progression. Remission is therefore not a cure (restitutio ad integrum) but a resting phase of the disease activity.


Term for a complete movement cycle of a cyclical movement that is not performed in a highly repetitive manner, such as running, but is performed in a much lower number of repetitions, such as in strength training. A sequence of repetitions performed without interruption is referred to as a set.

Repositionable / Resettable / Reducable

The ability of a malposition or incorrect position to be corrected (usually externally). This is generally understood to mean the ability of the malpositioned body part(s) to be brought into the correct position through manual intervention by the person themselves or an examiner (the process is called reduction). Anything that can be repositioned or repositions spontaneously is, by definition, reducable. For example, an acquired foot deformity that is not very old may be reducible, but may lose this property over time due to an accumulation of secondary changes in the foot. In many cases, repositionable deformities have a chance of conservative treatment success, whereas the opposite, contracted deformities, generally do not.

Repositioning / Resetting / Reduction

To bring back into the physiological position. The term refers to anything that can leave its physiological position and become malpositioned, bones in joints, organs, fracture ends in the case of a fracture.

Residual volume

The volume in the lungs and bronchi that can not be exhaled after forced expiration.

Respiratory muscles

Muscles whose contraction leads to an expansion or constriction of the chest or abdominal cavity and which contribute to inhalation or exhalation. Normally, exhalation occurs automatically according to the force of gravity and muscle tension as well as the retractional forces of the lung as an elastic organ; force is then only required for inhalation. In addition to the inspiratory muscles (inhalation) and expiratory muscles, there are also inspiratory auxiliary respiratory muscles and expiratory auxiliary respiratory muscles. One of the most important respiratory muscles and the one that causes abdominal inhalation through its contraction is the diaphragm.

Respiratory volumes / Breathing volumes

In an unloaded state, a 70 kg man inhales and exhales a tidal volume of approximately 0.5 l per breath. With maximum inhalation by using all inspiratory respiratory muscles and inspiratory auxiliary respiratory muscles, he can also inhale an inspiratory reserve volume of around 2.5 liters. At the end of an unstressed exhalation, by using all expiratory muscles and auxiliary expiratory muscles, he can still exhale an expiratory reserve volume of about 1.5 liters of air. This means that the sum of the tidal volume, inspiratory reserve volume and expiratory reserve volume reaches a vital capacity of around 4.5 liters. After maximum exhalation, however, a residual volume of approx. 1.5 l of air remains in the lungs and bronchi, which cannot be exhaled, resulting in a total capacity of approx. 6 l. Another respiratory volume, which does not fit in this calculation but is important nonetheless is the dead space volume of approx. 0.15 l.

Restriction of motion (of flexibility)

Restriction of flexibility refers to any lower ROM in a joint in one physiological dimension of movement or in a combined direction of dimensions than is given by the physiological hard-elastic or firm-elastic limit of movement, regardless of the cause. Restrictions in flexibility should therefore not be confused with physiological movement limits. In practice, almost all movements have a soft-elastic, muscular limit of movement. One well-known exception is the extension of the middle joints of the extremities, which, depending on the exact geometric configuration of the joints and the flexibility of the overlying biarticular muscles, are predominantly limited by hard-elastic (elbow joint) or firm-elastic (knee joint) limits: if, for example, asumed there is no soft-elastic limit of movement in the knee joint for extension without or with only slight hip flexion, this changes with further flexion in the hip joint when a soft-elastic limit of movement arises due to the restriction of flexibility of the hamstrings.

The term restriction of flexibility refers to a dimension of movement or a direction of movement that is a combination of movement dimensions. In practice, most flexibility restrictions are acquired losses of muscular flexibility, which are mainly due to regular non-utilization of parts of the ROM that is basically possible according to the hard-elastic and fixed-elastic movement limits and the corresponding adaptation of the muscles. See also the corresponding graph for the ankle joint, which shows the statistical decrease in flexibility in the ankle joint in the two movement dimensions of plantar flexion / dorsiflexion and pronation / supination.

The remaining range of motion (also: „range of motion“) must be determined actively and passively, as the two can differ: in the event of a rupture of the only executing tendon (e.g. quadriceps tendon for knee extension), the corresponding movement (in this case knee extension) can no longer be performed actively, but can be performed by an examiner, i.e. it is greater passively than actively.
Another example is the flexion of the knee joint, which its flexors can perform up to approx. 150 before active insufficiency or passive insufficiency occurs. The examiner, on the other hand, can usually bend the knee joint noticeably further.

The range of motion of most joints can be represented as one-, two- or three-dimensional with a corresponding number of independent movement dimensions. In practice, the movements in the central area of the ROM are independent without any restriction, but towards the edges of the ROM the course of the muscles and their restricted flexibility often have an effect on another dimension when one movement in a special dimension is intended, so that independence appears to be disturbed.


Breathing restrictions are called restrictive if they result from a reduced capability of the lungs to expand. Then the vital capacity and total capacity are reduced. Causes include pulmonary fibrosis, pleural adhesions or restricted thoracic flexibility, such as in scoliosis and especially in hyperkyphosis of the thoracic spine, for example in the context of pronounced forms of osteoporosis, Scheuermann’s disease or ankylosing spondylitis. Restrictive limitations can be detected by measuring vital capacity.


Restraining ligament that holds tendons in an area close to the joint and prevents the tendons and the associated muscles from fulfilling their physical tendency to stretch from origin to attachment by the shortest route when contracting, which in the case of the superficial finger flexors and profound finger flexors originating from the medial epicondyle of the humerus, for example, would be extremely obstructive in many tasks, would make them extremely susceptible to injury and would certainly have had at least a massive negative impact on the development of the species.

Retraction (shoulder blade)

Retraction of the shoulder blade towards the spine. The muscles that cause this are the retractor muscles. The counter-movement is called protraction.

Retractors (shoulder blade)

Muscles that pull the shoulder blade dorsally and medially towards the spine. These are

  1. Trapezius
  2. Rhomboideus major
  3. Rhomboideus minor
  4. Latissimus dorsi

The rhomboids also cancel out the outward rotation of the shoulder blade.

Retroversion (arm / shoulder joint)

Movement of the arm in the glenohumeral joint in a dorsal direction, i.e. beyond standard anatomical position. Retroversion can also be referred to as dorsal abduction in the shoulder joint and as a continuation of frontal adduction in the shoulder joint. The countermovement ist called canceling out the retroversion or dorsal adduction.

Retroverters (arm / shoulder joint)

the muscles that perform retroversion in the shoulder joint: teres major, latissimus dorsi (to a certain point only), triceps (caput longum), deltoid (pars spinalis, pars acromialis partial).


important retractors of the shoulder blade, see M. rhomboideus minor and M. rhomboideus major.

Rotary joint / pivot joint / trochoid joint

see under joint shapes

Rotation (head)

Rotation of the head around its longitudinal axis (in standard anatomical position: to the left or right), see also: rotation of the spine.

Rotation (shoulder blade)

Movement of the scapula in the plane in which it mainly expands, i.e. with the inferior angulus (lower tip) outwards and upwards (called outward rotation) or back again inwards and downwards (called inward rotation). The rotation of the angulus inferior outwards and upwards (outward rotation) is a prerequisite for raising the arm above 90°

Rotation (spine)

Rotation of parts of the spine around its longitudinal axis. The individual vertebral segments, consisting of two adjacent vertebrae and the intervertebral disc between them (as well as the spanning muscles and ligaments), allow the upper vertebral body to rotate to varying degrees in relation to the lower vertebral body. This is typically caused by the autochthonous back muscles, by other trunk muscles such as the oblique abdominal muscles, or by forces acting on the trunk via the extremities. Within the autochthonous back muscles, the oblique system causes rotation, which simultaneously generates extensor moments as well as rotational moments. In addition to extension/flexion and lateral flexion, rotation is one of the three dimensions of spinal flexibility and, like the other two, only occurs in large areas, essentially the cervical spine, the thoracic spine or the lumbar spine or more than one of them at a time.

Rotation axis / axis of rotation

the axis around which a one-dimensional movement takes place. This is, for example, a line through a condyle of a moving bone. If the elbow joint is considered only in terms of the humeroulnar joint (the joint between the humerus and ulna: articulatio humeroulnaris), it is a pure hinge joint in which the forearm rotates about an axis across the ulna forearm bone between the shaft and olecranon, thus enabling flexion and extension of the elbow joint. If the range of motion is more than one-dimensional, there is a center of rotation.

Rotation center / center of rotation

the point around which a multidimensional movement takes place. This is usually a point in a condyle of a moving bone. If the acetabulum is idealized as part of a spherical surface, it is the center of the sphere in which the three-dimensional movement in the hip joint takes place: abduction/adduction, flexion/extension and exorotation/endorotation. If only a one-dimensional movement takes place, this is referred to as an axis of rotation.

Rotational torque

Torque acting on a joint in the direction of rotation.

Rotator cuff

Term for a group of muscles, including:

  1. Teres minor (external rotator and adductor)
  2. Supraspinatus (external rotator and initial lateral abductor)
  3. Infraspinatus (strongest external rotator)
  4. Subscapularis (adductor muscle and most important internal rotator)

Together with the coracohumeral ligament, they form a tendon cap around the humeral head and the glenohumeral joint. Together they fix the humeral head in the glenoid. Some authors consider the term to be outdated.

Rearfoot running (heel running)

The most common running style in recreational sports and over long distances. The foot touches down with the heel, with the touchdown point clearly in front of the body’s center of gravity. On landing, the knee must be slightly bent in order to absorb the impact muscularly. In the standing leg phase, the knee joint is bent by up to 40° and the pelvis tilts forward significantly, especially if the gluteal muscles are weaker. In the push-off phase, the hip joint is only extended to around 0°, meaning that the leg is just in extension of the upper body. The pelvis remains more or less tilted forward.

Advantages: easy to learn as it is easier to derive from your usual walking, less effort required than forefoot running. Rearfoot running is easy to learn, reasonably energy-efficient, although not as much as forefoot running and not as demanding in terms of coordination.

Disadvantages: higher joint stress (ankle, knee joint, hip joint) when landing than with forefoot running, deceleration of propulsion on landing with loss of energy, tendency to Achillodynia, heel spurs, greater tendency to meniscus damage (outer menisci with knock knees, inner menisci with bow legs ), greater tendency to patellar lateralization. However, the effect of the impact is actually less than often assumed in the past. More recent findings show that the foot adapts to the running technique and the hardness of the surface.

Resting heart rate / Resting heart rate / Resting heart rate

see the dedicated page resting heart rate


see the dedicated page on rowing


see the dedicated page on running


Sacrospinal system

the muscles that run between the iliac crest and spinous processes of the vertebrae and belong to the lateral tract of the autochthonous back muscles: longissimus: (thoracis, cervicis, capitis) and iliocostales (lumborum, thoracis, cervicis), which, unilaterally innervated, flex the spine laterally and extend it innervated on both sides.

Saddle joint

see under joint shapes


Direction from anterior to posterior, i.e. vertically, in a vertical plane through a person standing in standard anatomical position, i.e. the plane in which an arrow shot at the person from the front flies. See also sagittal plane.

Sagittal plane

A vertical plane through a person standing in standard anatomical position from ventral to dorsal, i.e. – eponymously – the plane in which an arrow shot at the person from the front flies. The central sagittal plane through the symphysis, linea alba, midline of the sternum and the nose is called median plane.


The sarcomere is the smallest functional unit of the muscle. It is bordered on both sides by so-called Z-discs, on which the actin filaments hang, into which the myosin filaments engage, which are attached to the so-called M-disc in the middle of the sarcomere. Myosin is the motor protein that can cause a change in the geometry of its head by splitting ATP and can dock onto changing positions of the actin filament, thereby changing the length of each individual sarcomere and thus that of the muscle. During concentric contraction, the sarcomere shortens its length. Its average resting length is 2-2.5 µm, minimally it is a little over 1 µm, with significant elongation it approaches well over 4 µm. The protein titin is responsible for the elasticity of the muscle, specifically for the recovery of the sarcomere after stretching. At an impressive 3.6 megadaltons (1 dalton is 1/12 of the mass of a carbon atom), it is the largest protein in the human body. For a more detailed description of the sarcomere, see Wikipedia.

Sarcomere length

the sarcomere length is the actual length of the sarcomere, i.e. the distance between two Z-discs and therefore a measure of how far a muscle can still contract or how far it can still stretch. The average resting length of a sarcomere is around 2 – 2.5 µm, at just over 1 µm the muscle is fully contracted and no further contraction or shortening of the muscle is possible. The maximum length of a muscle is reached at just over 4 µm.

Inclined system

the part of the autochthonous back musculature that laterally flexes the spine, a list can be found there.


scalable means adaptable to requirements, variable, without having to make categorical changes. A simple example is the combustion engine as a heat engine. If more power is required, e.g. for greater acceleration or a higher speed (the nesessary work increases disproportionately against the air resistance with velocity), it is sufficient (simplified) to supply it with more fuel (air mixture) to a corresponding, but not necessarily exactly proportional extent. This is only natural, as power over a fixed time is equivalent to the energy content of the fuel used. In yoga poses, many factors are not scalable if the effect is based purely on the gravitational force of a partial body weight. For example, the degree of contraction of the deltoid in warrior 2 pose (if there are no lateral adductors of the shoulder joint in action) is mainly dependent on its maximum force and the gravity of the arm itself, and of course also on its length in the sense of the lever law. The stretching effect in the hamstrings in uttanasana is also not scalable if neither the lower legs are pulled with the arms nor the hip flexors are used to promote hip flexion beyond the degree induced by the partial body weight. If, on the other hand, one of these methods is used in addition, the pose is generally well scalable. In the same way, the strengthening of the pectoralis major and triceps related to a fixed time interval in staff pose is restricted for a given position of the hands because the partial body weight held is not variable but fixed. The staff pose only becomes scalable by changing the duration or the lever arm at which the muscles mentioned have to hold the upper body, i.e. when the hands are placed closer to the pelvis.

Scapular dyskinesia

Insufficient flexibility or inadequate movement pattern of the scapula during its movements on the trunk (in the scapulothoracic sliding bearing) or during arm movements. The main causes are muscular imbalances and weaknesses as well as tears in the rotator cuff muscles. In the most common form of scapular dyskinesia, a scapula alata is seen with a lowered, internally rotated arm due to a GIRD (glenohumeral internal rotational deficit) with additional painful wide external rotation of the arm against resistance, based on a shortening of the external rotators and the protractors with weakness of the retractors of the scapula, a general weakness of the muscles that fix the scapula to the back, i.e. in addition to the shortened serratus anterior, above all the rhomboids. Signs of subacromial tightness or impingement syndrome are also frequently found.

Sciatic nerve

The common fibular nerve and tibial nerve, which are wrapped together in connective tissue, are referred to as the „sciatic nerve“. Both emerge independently from the lumbosacral plexus, but pass through the intrapiriform foramen in a common sheath. The sciatic nerve supplies the lower extremity, with all flexors (exception: biceps femoris caput breve) of the knee joint and talocrural joint being supplied by the tibial nerve and the extensors and pronators of the ankle joints being supplied by the common fibular nerve. If the nerve is irritated or compressed in its course, whether it is the underlying spinal nerves or the sciatic nerve in its course in the dorsal hip area, disorders such as sciatica or lumbalgia or ischialgiform or lumbalgiform pain occur. However, these can also be caused simply by compression by a muscle, as in piriformis syndrome/deepgluteal syndrome DGS. Similar disorders also occur if the relevant nerves are compressed while still in the spinal canal, such as in spondylolisthesis or spinal canal stenosis, so that these disorders must be distinguished in a differential diagnosis. In some cases, this is already possible with the help of anamnesis and provocation tests, otherwise imaging such as MRI must be used. Irritation of the sciatic nerve can also be triggered by the effects of cold or pressure (sometimes associated with DGS ). Similar pain occurs in facet syndrome, but it is pseudoradicular and not radicular and does not cause muscular or sensitive deficits.


see the dedicated page for swimming

Segment (spinal column)

Two vertebrae with the intervertebral discs in between and the connecting ligaments. The segment is the unit in which the movements take place and therefore corresponds to a „vertebral joint“.


The sensitivity of a test refers to the probability that patients are recognised as such by this test. A low sensitivity therefore means a high false negative rate.

Sesamoid bone

A small bone embedded in or superimposed on a tendon to protect the tendon or underlying structure or to increase the lever arm of the tendon so that the executing muscle can achieve a greater moment. The sesamoid bone is therefore a hypomochlion.


A sequence of repetitions performed essentially without interruption. Usually several sets are performed in succession in training sessions, often with increasing resistance (such as a weight) and decreasing numbers of repetitions. Depending on the ambition and level of training, it is not uncommon to end up with sets with only around 4 repetitions, which already corresponds to around 89% of the 1RM.

Shoulder girdle

The shoulder girdle consists bony of the two scapulae and the two clavicles, which are connected ventrally to the sternum, which is not part of the shoulder girdle. In contrast to the closed pelvic girdle, the shoulder girdle is open dorsally. The musculature of the shoulder area consists of four groups:


Shrugging is the colloquial term for moving the shoulder blades, including the arms attached to them, upwards, i.e. cranially. Anatomically, this corresponds to their elevation and is achieved, among other things, by the contraction of the trapezius (pars descendens) and the levator scapulae. In everyday life, the arms usually rest against the body. In yoga poses, elevation, i.e. „the state of the shrugged shoulders“, is often found in poses with 180° frontal abduction in the shoulder joints (glenohumeral joints) such as downface head or handstand.

Side discrepance

As a rule, a side discrepance refers to a muscular imbalance in which one or often consecutively several muscles contralaterally have a different tone (and often also a different flexibility) than ipsilaterally. side discrepancies are therefore more or less pathogenic, depending on the extent and the muscles affected. For example, a side discrepance in the hip flexors and hip extensors can result in pelvic torsion and a consecutive disorder of the SI joint, or a lateral difference in the adductors and abductors of the hip joint can result in pelvic obliquity and a consecutive scoliosis. The extent of the disorder depends on many factors, including on the one hand the extent of the side discrepance, but on the other hand also the level of flexibility at which it occurs and thus also the extent of the influence on daily posts held for longer periods.

Side-by-side comparison

In some situations, due to the individual fluctuation of the parameters of the musculoskeletal system, a comparison between the two sides of the body is much more meaningful than a comparison of this parameter with other people or with a reference range to be read off. In particular, side discrepancies, even if the values on both sides lie within a reference range, tend to have an effect in other areas of the body and cause consequences there, and are often pathogenic.

Sitting giant

A sitting giant is a person whose upper body is particularly long compared to their legs. In most cases, the other limb is also longer in relation to the upper body: the arms. The arm-upper body ratio can be tested very easily: if the wrists are clearly above or at the greater trochanter of the femur in standard anatomical position, we see a sitting giant and wrists significantly below the greater trochanter, we see normal proportions or even a sitting dwarf. See also the exploration: sitting giant.

Sitting dwarf

The opposite of a seating giant, see there.

Scapulohumeral muscles

Muscles that pull from the shoulder blade (scapula) to the upper arm bone (humerus) to move the arm:


A limit of flexibility in a joint that is given by muscles is referred to as soft-elastic, see also end-degree position.

Sore muscles

Muscle soreness is the pain phenomenon that occurs as a result of mechanical damage to Z-discs. The Z-discs become torn as a result of high stress, especially eccentric contraction (which can be significantly stronger than concentric contraction), particularly braking movements, or intensive stretching. This is followed by an aseptic inflammatory process with migration of water and formation of a slight edema. As the muscle fibers have no pain receptors (but do have stretch receptors), pain only occurs with a delay of 12 to 24 hours when certain substances involved in the inflammatory process escape from the sarcomere and come into contact with nerve endings.

The explanation that it is a lactic acid build-up is outdated: the half-life of lactate is 20 minutes, so the delayed onset of muscle soreness does not correspond to its breakdown. In addition, muscle soreness also occurs during strength training, during which little lactate is produced. However, the 400m run, which produces a lot of lactate, generally results in less muscle soreness. Stretching before or after intensive muscle strain has no great influence on the development of muscle soreness. However, a good warm-up reduces the risk of injury and improves performance. Gentle (not vigorous) massages reduce the expected muscle soreness a little, as they promote blood circulation; vigorous massages are counterproductive, as they mechanically irritate the muscles too much. Heat treatments relieve the pain and promote healing because they stimulate blood circulation. Preventive or post-exercise large doses of protein reduce muscle soreness, with BCAA (branched-chain amino acids) having the best effect.

If training takes plave predominantly in very long sarcomer length so intensively that muscle soreness occurs, longitudinal muscle adaptation can occur and is probable, i.e. the muscle increases the number of serial sarcomeres (this is usually a 4- or 5-digit number) in order to be better able to cope with a further, similar load, as the larger number of serial sarcomeres makes the working range (in terms of sarcomere length) more favorable, i.e. it shifts from the upper limit slightly below 4.5 µm towards the medium length (approx. 2.5 µm), which has the advantage that the deployable force in terms of the force-length function becomes greater.

In less mobile people an good example of this is the rectangular uttanasana or the deep deadlift, which affects the hamstrings as it has to hold a large partial body weight (plus an external weight in the case of the deadlift) in a very long sarcomere length.


The specificity of a test refers to the probability that healthy people who do not suffer from the disease being tested for will actually have a negative test result. A low specificity therefore means a high false positive rate.

Spinal canal

The spinal canal in which the spinal cord runs and from which the spinal nerves emerge through the vertebral foramina.

Spinal cord

(lat. medulla spinalis or medulla dorsalis) part of the central nervous system that runs in the spinal canal. The spinal cord ends caudally as the conus medullaris (medullary cone) in the L1 / L2 area, where the nerves continue to run individually as the cauda equina. The existence of a spinal cord is common to all vertebrates. It is enveloped by meninges (from outside to inside: dura mater, arachnoid, pia mater), which in turn are surrounded by cerebrospinal fluid. Cranially, the spinal cord emerges from the medulla oblongata above the foramen magnum. The spinal cord contains the gray and white matter. For a more detailed description, see Wikipedia, for example.

Spinal nerve

The spinal nerves are the nerves that emerge from the spinal cord in pairs (right/left). From their exit from the spinal cord, they are part of the PNS. The spinal nerv es unite the anterior and posterior afferent and efferent nerve roots: afferents with sensory information enter through the posterior nerve root (radix posterior), efferents with motor nerve fibers and partly also fibers of the vagus nerve exit through the anterior nerve root. Pressure on a nerve root or the spinal nerve containing it can lead to a nerve compression syndrome. The nerve roots already join in the spinal canal.

Spinotransversal system

the muscles belonging to the lateral tract of the autochthonous back muscles that run between the spinous processes and the transverse processes of various vertebrae further cranially: splenius with cervicis and capitis parts, which rotate the cervical spine innervated on one side and lateral flex it innervated on both sides.


Arthrodesis of one or more segments of the spine.


Osteophyte occurring at the vertebrae, i.e. at the facet joints or at the edges of the upper and lower plates of the vertebral bodies.


Formation of osteophytes on the facet joints of the spine (spondylophytes). Spondylophytes and osteophytes in general are sometimes interpreted as an attempt by the body to enlarge the joint surface and thus relieve osteoarthritic/arthrotic or chondrotic areas. Atiologically, however, it is simply a matter of cartilage material being moved out of the contact surfaces of the joint and calcified there.

Sport in growth

see the dedicated page on sport in growth


see the dedicated page on sprinting

Standard anatomical position

Upright posture in which the feet are parallel and closed, the knees are stretched, the pelvis is upright, the upper body including the cervical spine is stretched and the arms rest against the body in such a way that the inner elbows and palms – in contrast to Neutral zero – point forwards. This means that Standard anatomical position corresponds approximately (!) to a savasana tilted 90° upright. Standard anatomical position is likely to have originated from the position in which most dissections were (and still are) performed in medical history in order to explore the human body.

Standing leg

The term standing leg refers to the one of the two legs that carries the body weight alone or carries a larger part of the body weight. The other leg is referred to as the free leg. This definition shows that the transition of a leg from the status of the standing leg to the status of the free leg can be fluid. In sports with a flight phase, such as running, no smooth transition is possible, but the standing leg and free leg alternate constantly (cyclical movement). Depending on the movement sequence, the standing leg not only carries the partial body weight (in this case the entire body weight minus that of the leg) but also kinetic (dynamic) loads, which can be many times the body weight, for example when landing from a jump, up to 7 times the body weight, for example in a block jump in volleyball.

Start-up pain (running-in pain, starting pain)

Pain that occurs at the start of an activity, movement or task and subsides as it progresses. This type of pain is typical of osteoarthritis/arthrosis and arthritis, but also other degenerative joint changes, especially in the hip joint and knee joint. In the case of osteoarthritis/arthrosis, the disease progresses over the years and the initial start-up pain often turns into continuous pain on exertion and later also pain at rest. In osteoarthritis/arthrosis, both are particularly pronounced in arthritic episodes.

Steep position

A steep position is usually defined as the loss of the physiological lordosis of the lumbar or cervical spine or the loss of the physiological kyphosis of the thoracic spine with transition of that area to a flat position. The steep position results in a change in the statics and the loss of the spring function of the area. The body must counteract the altered statics with compensation in distal and/or proximal areas so that the center of gravity of the partial body weight of the upper body, head and arms does not change too much, which would lead to a permanently increased muscular demand on the postural apparatus. In addition, the term steep position is also used for other parts of the musculoskeletal system that are physiologically inclined at a certain angle to the longitudinal axis of the body, such as the tarsal bones or the sacrum.

Stretching pain

Pain sensation triggered by stretching, i.e. transferring a muscle into borderline large or increasingly larger sarcomere lengths, typically radiating in the direction of the muscle course. Physiologically, stretching pain is scalable from NRS 0 to 10 and subsides significantly within seconds after the end of the application of force to the muscle with only a short reverberation. The proprioceptors that report stretch pain are the muscle spindles.

Stretching tenderness/painfulness / pain on stretching

Stretching tenderness refers to the ability of a part of the musculoskeletal system (usually the muscle and its tendon) to show tenderness under actively (by force application of the antagonists) or passively induced stretching of the muscle, which goes beyond the physiological level of stretching sensation or shows a different quality of pain. Various diseases of the muscle (e.g. ruptures, strains, muscle bruises) or the tendon (e.g. insertional tendinopathies, tendovaginitis) can be associated with pain on stretching.

Stress-induced pain

The pain that is triggered by stressing painful parts of the musculoskeletal system.

Stress-induced painfulness

The ability of a muscle, its tendon or another structure of the musculoskeletal system to show pain on exertion, i.e. to show pain under load that has a different quality than „exertion“ or „stretching sensation“, i.e. is of a different origin than from the proprioceptors Golgi tendon organ or muscle spindle.
The load can be your own body weight or an external weight. The load from your own body weight can be, for example, a squat, climbing stairs or the muscle work required for fast walking or running. Stress-induced pain mainly affects the musculoskeletal system and is usually, but not always, caused there.

Structural pain

Structural pain, like its conceptual opposite, functional pain, is not sufficiently clearly defined. Structural pain is pain caused by a (often: not too complex) detectable disorder such as inflammation, a fracture, a bursitis, a torn muscle fiber or osteoarthritis/arthrosis.

Suboccipital system

the muscles running from the vertebrae to the occiput:

  1. M. rectus capitis posterior major
  2. M. rectus capitis posterior minor
  3. M. obliquus capitis inferior
  4. M. obliquus capitis superior

Support base (physical support base, also: PSB)

Convex envelope of the set of load-bearing points of a body in the plane, regardless of whether the plane is horizontal. In the case of a square table, this is the smallest rectangle that encloses the table leg contact surfaces with the floor.


After completing regeneration from heavier training or intensive physical work of a non-sporting nature, the body is said to ensure a slight increase in performance. This theory is known as supercompensation theory. Supercompensation therefore describes the (rather limited) phase of increased performance as well as the effect as such. The body tries to arm itself a little against the type of demand or overload. The supercompensation phase begins immediately after complete regeneration, the performance level slowly rises by a small amount up to a maximum increase, only to then slowly fall again and finally return to the original performance level you had before the training. Now, of course, you would want to place the next training session directly into the maximum of supercompensation in order to exploit this effect again at a slightly higher level. And again and again. However, the increase in performance does not develope proportionally without end, but probably follows more of a logarithmic curve, so that the achievable increase decreases further and further towards the end or disproportionately more effort has to be put in for the same increase. The supercompensation curve must therefore be taken into account for optimal training, although this is difficult to predict or calculate in general terms. They are very individual and depend on the type and intensity of training.


refers to a position close or (in comparison) closer to the head. The conceptual opposite is inferior.

Supination (foot)

in standard anatomical position, the tilting movement of the foot around its longitudinal axis (in the sublatar joint), which is caused by lifting the inner foot in relation to the outer foot

Supination (forearm)

the rotational movement (reversal of the overturning movement) of the radius over the ulna, which brings the two forearm bones (ulna and radius) closer to their parallel course as it corresponds to standard anatomical position with the palms facing forwards. With the arm extended forwards and turned out at the shoulder joint, this corresponds to an upward-facing palm, in other terms, with a bent arm, the palm point towards the biceps.

Supinators (foot)

All muscles that supinate the foot, i.e. lift the medial edge of the foot. These are: M. triceps surae, M. tibialis posterior, M. flexor digitorum longus, M. flexor hallucis longus, M. tibialis anterior.

Supinators (forearm)

All muscles that supinate the forearm, i.e. the biceps, which supinates the forearm a little from a pronated position, the brachioradialis, supinator, extensor carpi radialis longus, extensor pollicis longus, extensor pollicis brevis, extensor indicis. See also: elbow joint.


State of increased excitation of the sympathetic nervous system.

Sympathetic nervous system

The sympathetic nervous system is the part of the autonomic nervous system that controls the increase in performance and mobilization of energy reserves. These effects are referred to as ergotropic. It is largely antagonistic to the parasympathetic nervous system. On the heart, the sympathetic nervous system is positively chronotropic, positively dromotropic (accelerating stimulus conduction), positively inotropic (increasing contraction force), positively bathmotropic (lowering the stimulus threshold), positively lutitropic (promoting relaxation) and thus increases cardiac output in every possible way. In the blood vessels it has a vasoconstrictive effect, dilates the bronchi and inhibits mucus production and liquefies mucus, in the gastrointestinal tract it reduces gland secretion and peristalsis, in the genitourinary tract it tightens the bladder sphincter and weakens the detrusor vesicae muscle, in the eye it causes mydriasis (dilation of the pupil) and generally leads to increased sweat secretion. Increased excitation of the sympathetic nervous system is referred to as sympathetic tone and has a weakening effect on HRV.

Symphysis (pubic symphysis)

The pubic symphysis (symphysis pubica) between the left and right pubic bone. It plays a role during pregnancy because it widens under hormonal control, see also symphysis. The small movements possible here also play a role in many movements.

Symphysis (in general)

Symphyses in the actual sense are connections of bones through fibrocartilage, and therefore belong to the articulationes cartilagineae like the synchondroses. The best-known symphysis is the pubic symphysis (symphysis pubica) between the left and right pubic bone. An intervertebral disc (interpubic disc) lies in the symphysis, which keeps the joint mobile. This flexibility can be felt in various poses and used as a marginal effect, for example by stretching in the ischial joint in forward bends. The connection between two vertebrae (intervertebral symphysis) is also a symphysis. The connected bones form a symphysis with the intervertebral discs (and accompanying ligaments).


A synchondrosis is a cartilaginous connection between two bones. It is therefore not a true joint but belongs to the articulationes cartilagineae. Normally, hyaline cartilage connects the bones. If it is fibrocartilage instead, it is referred to as a symphysis. Examples include the cartilage between ribs 1, 6 and 7 and the sternum (synchondroses costosternales), between the sphenoid bone and the occipital bone (synchondrosis sphenooccipitalis) or between the sphenoid bone and the petrous bone (synchondrosis sphenopetrosa). The cartilage connection between the three parts of the sternum (synchondroses sternales) are symphyses.


A syndesmosis is a connective tissue (collagen or elastic) connection between two bones. It is therefore not a true joint, but belongs to the articulationes fibrosae. The connecting membrane is usually also the attachment area for muscles. In contrast to the synchondroses, which are mainly subjected to pressure, syndesmoses are mainly subjected to tension. The presence of syndesmoses does not mean that the articulating bones have no real joints with each other. Important counterexamples are the syndesmoses between the ulna and radius (interosseous membrane antebrachii) or between the tibia and fibula (interosseous membrane cruris).


muscular co-actor that (at least partially) performs the same movement, i.e. supports the agonist. In many cases, muscles are only partially synergistic because most muscles serve several dimensions of movement simultaneously.


Synovia refers to both the joint fluid, which contains the nutrients required by the cartilage coverings of the bones and to which the cartilage releases the metabolic end products under pressure, and the innermost layer of the joint capsule, which produces this fluid. The fluid is also commonly referred to as „synovial fluid“. In terms of low-molecular substances (less than 100,000 Daltons), the joint fluid is largely a dialysate of the blood serum, but has a different protein composition, for example the coagulation factors prothrombin, proaccelerin, proconvertin and fibrinogen are missing, so it is not capable of clotting. Physiologically, it contains hardly any blood cells, mainly lymphocytes. It is enriched with mucins by the synovial B cells of the synovial layer, including above all hyaluronic acid, which belongs to the non-exchangeable phase of the synovia and whose content significantly determines the viscosity of the synovia. Cold changes the viscosity of the synovia adversely and the lubricating effect of hyaluronic acid decreases.


Inflammation of the synovium, often caused by overuse; ergonomic or material deficiencies are a further risk factor, as is a lack of regeneration.



Tachycardia is the term used to describe a resting heart rate that is significantly higher than the age-related physiological rate, i.e. around 100 beats per minute in adults. In addition to disorders of the heart itself and drug use, psychogenic factors can also play a causative role. See also bradycardia.


Tachypnoea refers to an increased breathing rate at rest, over 20 breaths in adults. In the physiological case, the respiratory rate depends on the oxygen demand of the tissues, i.e. it is increased during physical activity. At rest, it is usually between 12 and 16 breaths per minute, in newborns between 30 and 50, in premature babies up to 80. It can increase massively during exercise, but a certain amount of tachypnoea is also common in cases of fever and various illnesses. A breathing rate that is too slow is called bradypnoea.


Tachytrophic tissues are those with a fast metabolism and short turn over. These tissues renew themselves quickly, adapt quickly and heal quickly. They are rarely affected by overuse syndromes. The conceptual opposite of tachytrophic is bradytrophic.

Tarsal tunnel

Medial depression in the area of the tarsal bones between the talus, calcaneus and inner malleolus, through which the tibial nerve, the posterior tibial artery and the tendons of the posterior tibial muscle, the flexor digitorum longus and the flexor hallucis longus run. The tarsal tunnel is covered by a retaining ligament, the flexor retinaculum. Swelling of the tendon of the tibialis posterior muscle can lead to pressure on the nerve and thus to tarsal tunnel syndrome, a nerve compression syndrome.

Tenderness on palpation

Pressure pain / pressure dolence / tenderness on palpation refers to the current property of a body part to produce pain sensation (pressure pain) in response to external pressure. In most cases, the quantity of the transmitted pain sensation („intensity“) is monotonically dependent on the amount of pressure exerted. The resulting pain is referred to as pressure pain. It must not be confused with tension pain, which occurs without external intervention such as palpation.


Inflammation of a tendon. This can occur together with or without inflammation of its tendon sheath (tendovaginitis) and is then also referred to as tendosynovitis. The cause is usually overuse.


A tendon (lat. tendinum) is a connective tissue, non-contractile part of a muscle that connects the contractile part (muscle belly) to a bone. In some cases, muscles also attach to other tendons, fascia or directly to bones. It is not uncommon for tendons of several muscles or muscle bellies to confluence into one. Near joints, tendons often run in a connective tissue sheath, the tendon sheath. They are often padded with bursae to protect them from bone pressure. Tendons consist of parallel, firmly connected fibers and are round or flat, depending on the shape of the muscle. Tendons are generally weakly vascularized and therefore belong to the bradytrophic tissues, which increases their regeneration time or turn over. They therefore belong to the bradytrophic tissues. They are supplied approximately one third each by their muscle, by the periosteum of the bony insertion site and by the lymph flow. The sensitive innervation is also rather low. The Golgi tendon organ, which measures tendon strength, is one of the most important proprioceptive receptors in the transition from the contractile to the tendinous area of the muscle. Tendons have an elasticity of up to about 15%. Neueren Forschungen zufolge wirkt ein Ionenkanal-Protein in den Sehnen als Kraftsensor, der die Längsverschiebung von Kollagenfasern gegeneinander detektiert. Bei größeren gemessenen Scherkräften emittiert der Kraftsensor Calciumionen ins Innere der Sehnenzellen, was die Produktion von Enzymen fördert, die die Fasern miteinander verbinden, was die Steifigkeit und Belastbarkeit auf Kosten der Elastizität steigert. Von diesem Ionenkanal-Protein gibt es mehrere genetische Varianten. The E756del variant, which originated in West Africa and is the result of a counter-reaction to malaria plasmodia, causes an excessive release of calcium, which results in firmer tendons. Carriers of this variant have an advantage in sports where the condition of the tendons is important (high-speed sports such as sprinting, fast jumping disciplines).

Tendon force

The force with which a muscle pulls on its attachment and origin. In the simplified model, a muscle attaches to a bone with a tendon at both the origin and the attachment. If you were to cut a tendon and insert an element to measure the traction force, you would obtain the tendon force of the muscle. The actual tendon force depends on the resting tone, the positions of the covered joints and, of course, the innervation to a high degree. Even without voluntary innervation, a muscle has a certain resting tone, so the tendon force is different from zero even in the most favorable joint positions. If the tendon were to be severed on one side, the head of the muscle would contract.

Tendon sheath / vagina synovialis tendinis

The tendon sheath is the double-walled connective tissue covering of the tendon in which it glides. It is directly enveloped by a two-leaf stratum (inner and outer leaflet). The inner leaflet is fused with the tendon, the outer leaflet with the stratum fibrosum, the outer part of the tendon sheath. Between these two strata lies a buffer of synovia, which produces the synovial layer of the joint capsule, to which the inside of the tendon sheath is connected.

Tendopathy / Tendinopathy

Tendon disorders with no specified etiology, but usually of an inflammatory or degenerative nature. Overuse is a common cause, with ergonomic or material deficiencies being a risk factor, as is a lack of regeneration.

Tension belt / strong rope

Anatomical principle for the relief of bone structures by soft tissue structures. Probably the best-known tension belt is that of the femur: the relief of the femur formed by the iliotibial tract, which absorbs the significant moment that occurs in particular in the angle between its shaft and neck (the CCD angle of physiological 120° in adults), but also in the long shaft of the bone as a bending moment. When the leg bears weight with the knee joint even slightly bent, the quadriceps and thus also its vastus lateralis tenses, therefore its volume or cross-section increases the effect of the tension belt.

Another tension belt is found in the foot: without the plantar fascia, the longitudinal arch of the foot would tend to collapse in a plantar direction under the static load of the body weight and the dynamic loads when walking and running. The tension belt provided by the plantar fascia absorbs this as a passive tension belt together with the muscles of the foot as an active tension belt. The tension belt is therefore twofold, on the one hand passive (plantar fascia and ligaments such as the plantar long ligament in particular) and active through some intrinsic foot muscles. The weakening of one component, for example the active component due to a lack of training stimuli or overloading, quickly leads to overloading and thus to weakening of the other component, in this case fallen arches result and later a flat foot.

Tension pain

Tension pain is pain that occurs due to increased tension in tissues that have receptors to register this type of change from the physiological state and transmit it to the brain. Tension pain should not be confused with pressure painfulness (pressure dolence) or the pressure pain resulting from palpation. Herpes labialis is a classic example of clear tension pain with additional pressure painfulness (pressure dolence): there is already a painful sensation of tension without touch, which can be further increased by touch or pressure. The pain quality of tension pain is generally described as „pressing“ or „oppressive“, as is the case with pressure pain.

Terminal / end-degree (movement, position)

A joint position is called terminal when no further movement is possible in its direction, seen from the center of the ROM. This direction in which the movement limit occurs does not have to correspond strictly to a single movement dimension, but can be a combination of several. This definition is independent of the number of movement dimensions of a joint, so it applies to both the one-dimensionally mobile elbow joint and the three-dimensionally mobile glenohumeral joint or hip joint. This definition also does not require an exact breakdown of the movement into the movement dimensions. The limit of movement can be set physiologically by different structures and is perceived by the examiner in different ways during a passive examination:

  1. Muscles: soft-elastic end feeling (e.g. restriction of hip flexion with the knee joint extended by the hamstrings)
  2. Ligaments: firm-elastic end feeling (e.g. limitation of inversion and eversion of the ankle complex by various ligaments)
  3. the bony joint structure, i.e. the cartilage of the articulating joint partners: hard-elastic end feeling (e.g. touchdown of the olecranon to the humerus in the elbow joint on full extension)

The soft-elastic case, i.e. the limitation of movement by muscles, can be influenced to a significant extent by training, for example by stretching training, which increases the flexibility of the muscles through (positive) longitudinal muscle adaptation. On the other hand, unfavourably selected prolonged immobilization can lead to negative longitudinal muscle adaptation and a reduced number of serial sarcomeres and thus to reduced muscle flexibility. On the other hand, a muscle can adapt to heavy loads and increase in strength and circumference, which, depending on how it is performed, can also reduce the flexibility of the muscle. However, any type of sports training should not attempt to change the non-muscular limits: in the case of cartilage, this would by definition result in osteoarthritis/arthrosis; in the case of ligaments, it would result in ligament laxity, hyperextensibility or ligamentary insufficiency, which also is a predisposition to osteoarthritis/arthrosis due to the excessive displacement of the bones in relation to each other in terms of extent or type.

Terminal rotation

The terminal rotation of the knee joint is an involuntary external rotation of the lower leg in the knee joint of approximately 5°-10°, caused by the tension of the anterior cruciate ligament in conjunction with that of the iliotibial tract. In the standing leg with a fixed lower leg, we perceive it as an inward rotation of the thigh in the knee joint and an internal rotation of the thigh in the hip joint, whereas in a free leg we see it as an external rotation of the lower leg in the knee joint.
The final rotation represents a type of „physiological subluxation“ that brings the extended, loaded joint into a more stable state. In order to be able to bend the knee joint again, the popliteus, a largely transverse muscle that mainly turn in the lower leg and flexes the knee joint a little, must reverse the final rotation. It is supported by the knee flexors in the inner hamstrings, i.e. the semimembranosus, the sartorius and the gracilis. The onset of the ternimal rotation can already be detected at 20°-30° flexion in the knee joint, which is why the discussions about the extent to which or how pronounced the terminal rotation takes place during normal walking have not yet been concluded. This is certainly also dependent on the individual gait pattern.


The ball of the thumb, which contains important muscles for moving the thumb:

Thoracic spine

The middle part of the spine, consisting of 12 vertebrae, which lies between the cervical and lumbar spine and thus encompasses the entire upper body and, together with the ribs and sternum, spans the rib cage.

Thorax / Ribcage

The ribcage is the part of the torso spanned by the ribs and located above the pelvic and abdominal cavities. It partially covers the latter due to its dome shape. The rib cage is spanned by the ribs, which are attached to the thoracic vertebrae by two joints on the dorsal side and to the sternum by cartilage on the ventral side. This gives it a certain flexibility so that it can draw air into the lungs when inhaling. To do this, the costal arches are mainly pulled forward and upward, which increases the three-dimensional volume of the ribcage. This movement is caused by the inspiratory muscles, especially the scaleni and intercostal muscles. On the other hand, exhalation can occur passively when the rib cage contracts again due to the retraction forces of the lung tissue and, in an upright position, also by gravity of the ribcage. In addition to the lungs, it contains another highly vital organ, the heart. It serves as bony protection for both. In the middle of the chest between the two lungs lies the mediastinum, which contains the heart as well as large vessels and nerves. The thymus gland is also located in the mediastinum.

Tidal volume

The tidal volume is the volume that is inhaled and exhaled on average at rest, i.e. without strenuous activity. The population average is around 500 ml. The dead space volume, part of the tidal volume, of approx. 150 ml does not contribute to gas exchange.

Tiffenau Index

the focussed expiratory volume FEV1 that can be exhaled in one second, should be 70% of the forced vital capacity (VC ), i.e. the maximum forced inhalable volume. The Tiffeneau index of FEV1 / FVC should therefore be at least 0.7. On average, the index is 0.75 (75%), in healthy older patients it is closer to 0.7 (or 70%). The Tiffenau index is determined using the Tiffenau test.

Tilting moment

The tilting moment is the smallest moment that causes a body to tip over along the edge of its PSB in accordance with gravity. The tilting moment is therefore dependent on the PSB and the center of gravity.

Tonus (muscle tone)

Basic tension of the muscles. Force (measured at the attachment or origin) with which the muscles pull the origin and attachment towards each other. Generates a basic (rotational) moment in most joints of the musculoskeletal system.

Torsional moment

Torque acting on a body in the direction of torsion.


the rotational effect of a force acting on a lever arm on a solid body rotating around an axis. The torque is the product of the force (F in N Newtons) and the distance, i.e. the length of the lever r in m meters, and is therefore measured in Nm. In the case of a circular movement, the torque acts on a tangent to the arc of the circle at the point where the force is applied.

Total capacity

The sum of all respiratory volumes including the inspiratory and expiratory reserve volumes and the residual volume.

Total endoprosthesis (TEP)

A total endoprosthesis is a complete, often limited functional replacement of a joint. For information on the limitations and possible complications, see also pathology: status after endoprosthesis.


In physiotherapy, traction is a passive measure that pulls the articulating partners of a joint away from each other. This can serve to relieve cartilage or intervertebral discs, reduce muscle tone, stretch ligaments if necessary or reduce pressure on the nerves accompanying the joint. Traction is intended to stimulate the production of synovial fluid (joint fluid), which improves joint lubrication. Traction can be applied manually by the therapist (manual therapy) or with weights. Particular care must be taken if there is a risk of dislocation or hypermobility.

Training zones

The training zones are divided into 10 percent increments as follows:

  1. Health zone (regeneration, compensation): 50-60% of HRmax. Strengthening the cardiovascular system, good for beginners
  2. Fat-burning zone (basic endurance training 1): 60-70% of HRmax Strengthening the cardiovascular system, improving fitness, best fat burning
  3. Aerobic zone (basic endurance training 1-2): 70-80% of HRmax. Improvement of breathing and circulation, aerobic fitness, best promotion of endurance
  4. Anaerobic zone (basic endurance training 2): 80-90% of HRmax. Accumulation of oxygen debt, improvement of lactate tolerance, short-term training intervals for competitive athletes. The beginning of the anaerobic threshold is the „lactate threshold
  5. Red zone (competition-specific endurance training): from 90% of HRmax. Dangerous for recreational athletes.


Translation is a rotation-free movement of two joint bodies against each other. In flat joints, this can be a physiological movement, as a further (up to two) movement dimension(s) in addition to axial rotation. Translation is often referred to in connection with non-physiological movements in cases of joint instability. Pathological translations are therefore the unintended shifts of the bones in a joint, in the case of the knee joint, for example, lateral/medial and frontal/dorsal. Compression (the compression of a joint) and traction (the pulling apart of the traction (the pulling apart of the bones in the joint, as in physiotherapy, for example) is also a translation, even if the term is used far less frequently in this context.

Transverse / transversal

direction from lateral to medial or further to counterlateral, in other words a transversal direction is a vector in the line of intersection between the frontal plane and transversal plane through the person standing in standard anatomical position, or in short, from left to right or vice versa.

Transverse abduction (shoulder joint)

Horizontal abduction (in the transverse plane) while maintaining the degree of frontal abduction(anteversion). To a certain extent, this movement is possible without moving the scapula; beyond this, it forces further retraction.

Transverse adduction (shoulder joint)

Horizontal adduction (in the transverse plane) while maintaining the degree of frontal abduction (anteversion) To a certain extent, this movement is possible without moving the shoulder blade; beyond this, it forces further protraction.

Transverse plane

a horizontal sectional plane through the person standing in standard anatomical position.

Transversospinal System

Muscles that run between transverse processes and spinal processes of various vertebrae belonging to the medial tract of the autochthonous back muscles: Rotatores breves et longi (lumborum, thoracis et cervicis), Multifidi (lumbales, thoracici, cervicis), Semispinalis (thoracis, cervicis, capitis).

Trapezius line

In the area between the acromion and the neck, the trapezius forms the most cranial part of the body and thus part of the silhouette, still above the clavicle. If this area is viewed dorsally or ventrally, the trapezius rises from lateral to medial in standard anatomical position, i.e. with depressed shoulder blades; this part of the silhouette is referred to as the trapezius line. From a certain degree of elevation of the shoulder blades, the described rise from lateral to medial is lost. A trapezius line that does not rise medially can therefore be interpreted as a sign that the shoulder blades are not fully depressed. With fully elevated scapulae, the course of the trapezius line should be reversed: descending from lateral to medial. However, the extent of the possible elevation and thus this phenomenon depends on restrictions in the flexibility of the depressors of the scapula and the lateral and, above all, frontal adductors of the shoulder joint, which are indirect depressors of the scapula, especially with the arm raised.

Triceps coxae

Triceps coxae is the name for the three muscles that pull from the caudal-medial (gemellus superior of the ischium), medial (gemellus inferior of the ischium) and cranial (Obturatorius internus of the ilium) to the trochanteric fossa of the posterior femur and turn out the thigh in the hip joint. The external obturator muscle is not included, as it attaches ventrally to the ischium and but also turnes out the thigh in the hip joint.

Trochoid joint / rotary joint / pivot joint

see under joint shapes

Truncohomeral muscles

Muscles that pull from the trunk to the upper arm bone (humerus) to move the upper arm:

trunkoscapulare Muskulatur

Muscles that pull from the trunk to the shoulder blade to move it:

Tubular bone / long bone

Generally elongated bone with two ends (epiphyses) and a semi-cylindrical shaft (diaphysis) in which bone marrow is located. The epiphyses at both ends of the long bone are connected to the diaphysis by the growth zone (epiphyseal plate). Once growth is complete, the epiphyseal plates are closed. Apophyses are used for the development of insertions of ligaments and tendons.

Turn over, cell moulting, cell replacement

The time in which a tissue is completely renewed, or more precisely, in which differentiated cells of a tissue are replaced. In physiology, a distinction is made between bradytrophic and tachytrophic, i.e. slow and fast metabolizing tissues. The bradytrophic tissues include most tissues without (or with very little) their own arterial supply, i.e. most cartilage, ligaments and tendons. In contrast, cells in contact with the outside world generally have a higher metabolic rate; both the skin and mucous membrane cells that are obviously part of the human exterior and those of the mucous membranes of the digestive and respiratory tracts are tachytrophic. The parts of the CNS, on the other hand, do not renew themselves. On average, the skeleton renews itself every 10 years, the liver renews itself in 300 to 500 days. The renewal times of various tissues and organs calculated by Jonas Frisen (Karoslinska Institute):

  1. Small intestinal epithelium: 2-4 days
  2. Gastric mucosa: 2-9 days
  3. Cervix: 6 days
  4. Synovia (joint fluid): 7-14 days
  5. Alveoli: 8 days
  6. Taste buds: 10 days
  7. Thrombocytes: 10 days
  8. Osteoclasts: 2 weeks
  9. Intervertebral disc (gelatinous nucleus): 2 – 3 weeks
  10. Epidermal cells: 10-30 days
  11. Muscle tissue: 3 – 4 weeks
  12. Bone tissue: 4 – 6 weeks
  13. Lymph vessel tissue: 4 – 6 weeks
  14. Trachea: 1-2 months
  15. Sperm: 2 months
  16. Osteoblasts: 3 months
  17. Erythrocytes: 4 months
  18. Hepatocytes: 0.5-1 year
  19. Intervertebral disc (fibrous ring): 1 – 1.5 years
  20. Tendon tissue: 1 – 1.5 years
  21. Joint capsule tissue: 1 – 1.5 years
  22. Tape fabric: 1 – 1.5 years
  23. Fat cells: 8 years
  24. Skeleton: 10 years
  25. Heart: 100 years (increasing with age)
  26. Cartilage tissue: 200 – 400 years

These figures also result in different times for the healing of injuries: while mucous membranes and skin heal quickly and even bones, other, passive parts of the musculoskeletal system take significantly longer or, in the case of cartilage, even have a turnover that is beyond the lifespan.


Ulnar abduction (hand)

Reduction of the distance and angle of the hand and thumb to the ulnar side of the forearm.

Underhand grip

An underhand grip is a grip on an object, often a piece of sports equipment such as a dumbbell, in which the back of the hand points downwards, the object rests in the palm of the hand and the object or its handle is enclosed by the fingers through the force of the finger flexors. In contrast to the overhand grip, the forearm is in supination and the palmar flexors together with the finger flexors hold the weight. In the underhand grip, the brachialis and arm biceps are also powerfully engaged.


Underutilization of bodily functions leads to disorders. This term usually refers to the musculoskeletal system and means a quantitative lack of movement. If certain movement options are underutilized, however, this is narrowuse, defining a qualitative lack. In practice, underuse and narrowuse often occur together. A variety of effects can be observed here, from osteoporosis of the ageing, comfortable movement and exertion avoider to instabilities that develop in an underused musculoskeletal system due to a lack of training stimuli, through to the cartilage damage that can result from prolonged immobilization after injuries. Unintentional weight gain is well known as a symptom of a medium-term lack of exercise (and an inadequate calorie balance), but tests also show that massive underuse (a limit of a few hundred steps per day) leads to clearly demonstrable fatty degeneration of the liver and heart within 14 days. The decrease in cardiopulmonary resilience caused by underuse, the increase in the risk of heart attack, stroke, diabetes, obesity with its risk factors, arteriosclerosis and vascular dementia are also well known. But it is not only in anatomy and physiology that underuse has a pathological or pathogenic effect; the positive psychological effects of sufficient exercise behavior can also be demonstrated in the form of a reduced tendency to depression and better coping with everyday life, to name but a few.


Vagus nerve (N. vagus)

The vagus nerve is the antagonist of the sympathetic nervous system and the most important part of the parasympathetic nervous system. It is the 10th cranial nerve and is the only one that moves from the head into the trunk, hence its name „wandering“. Among other things, it controls digestion and calms the heart, see the effects of the parasympathetic nervous system and heart rate variability (HRV).


State of increased excitation of the vagus nerve.

Valgus deformity / valgus position

Malalignment in which a part more distal deviates laterally compared to the physiolocigal case. In the case of the knee, for example, this would be knock-knees; in the case of the big toe, it would be a position too close to the second toe, i.e. hallux valgus.

Valgus stress

Force acting on a joint (at least) perpendicular to its physiological direction of movement, which results from the distal body part being pushed laterally in relation to the proximal body part. In the case of the knee, for example, this would be a force that pushes the intermediate knee inwards (medially) when the pelvis and foot are fixed or pushes the foot laterally when the thigh is fixed. In asanas, a certain amount of valgus stress occurs in upavista konasana, for example, especially when it is performed against the wall or as a partner exercise in which pressure is applied to the lower legs or feet. Valgus stress also occurs in the lying version of upavista konasana if the heels are placed too low on the wall. To avoid valgus stress in the finger joints (especially the proximal and distal ones), the palm of the hand is placed on the floor in the sitting twist instead of the fingers at more or less right angles to the direction of the force exerted, as is often the case. If, e.g. the fingers were pointing away from the pelvis, this would create valgus stress in fingers 2-5 and varus stress in the thumb. In the case of knock-knees, the knee joint is exposed to valgus stress when the leg is loaded, i.e. in standing leg situations.


An anatomical variety is a deviation from the norm without functional or clinical abnormality or limitation, although this distinction is difficult to make clearly. One variety is the cervical rib, a unilateral or bilateral additional zeroth rib (an atavisumus, i.e. a recurrence of evolutionary relicts), which occurs in 1% of cases, is attached to the C7 and has a cartilaginous or connective tissue connection to the sternum. The cervical rib is usually inconspicuous and goes unnoticed; at best, it is discovered as an incidental finding during imaging. In some cases, however, it can also cause thoracic outlet syndrome.

Varus deformity / valgus position

Malalignment in which the distal part of the body deviates medially compared to the physiolocical case. In the case of the knees, for example, this would be bow legs.

Varus stress

Force acting on a joint (at least partially) perpendicular to its physiological direction of movement, which results from the distal body part being pushed medially in relation to the proximal body part. In the case of the knee, for example, this would be a force that pushes the knee outwards (laterally) when the pelvis and foot are fixed or pushes the foot medially when the thigh is fixed. In the lying version of upavista konasana, varus stress occurs if the feet are placed too high on the wall. If they are placed too low, valgus stress occurs. To avoid varus stress in the thumb joints (especially the distal joint), in sitting twist the palm of the hand is placed on the floor instead of the fingers at a more or less right angle to the direction of the force exerted, as is often the case. If the fingers were pointing away from the pelvis, this would result in valgus stress in fingers 2-5 and varus stress in the thumb. In the case of bow legs, the knee joint is exposed to varus stress when the leg is loaded, i.e. in standing leg situations.


denotes a direction and means „from or to the front“ and is identical to the term anterior or frontal. The conceptual opposite is dorsal, which in turn corresponds to the term posterior.

Vital capacity

Vital capacity is the sum of tidal volume, inspiratory and expiratory reserve volume and therefore the maximum amount of air that a person can inhale and exhale.


Walking (in general, in any form)

see this dedicated article.


Wetness or moisture is an important cofactor of cold, both in the form of liquid on the skin, as when swimming, and in the form of high humidity of the air. Even if cold air can bind less water vapor than warm air, the water content in the air is sufficient to extract heat from the body more quickly due to better thermal conductitity. This is very clear when we are in water: while we have a wafer-thin film of air on our skin when moving in the medium of air, which is largely held in place by our hair and prevents the temperature from dropping abruptly to outside levels, this is not the case when we are in water, especially when moving in water. If a person regularly spends long periods in the water, the body has to build up subcutaneous fatty tissue to protect itself from hypothermia. This effect can be seen regularly when comparing professional swimmers with terrestrial endurance athletes. The reduction of the film in which the temperature constantly drops and the resulting reduced protection against the cold is also known as the wind-chill effect in the air: the stronger the wind blows, the colder the air is perceived to be.

Windlass mechanism

The Windlass mechanism (winch mechanism) refers to the fact that the dorsiflexion of the toes towards the end of the rolling phase of the foot pulls the plantar plate of the metatarsophalangeal joints forwards (towards the tiptoe) and thus tenses the plantar fascia, which results in the forefoot being pulled towards the calcaneus and thus promotes the longitudinal arch of the foot. Under physiological conditions, the shortening of the distance between the metatarsal head and the calcaneus can be more than 1 cm, and the longitudinal arch of the foot is promoted accordingly. The Windlass mechanism can be impaired by a variety of disorders of the foot. This loss of function cannot be compensated for with orthoses.

Working heart rate / working pulse

The working heart rate is the amount by which the heart rate increases during exercise compared to the resting heart rate.

Working point

The point in the ROM at which a muscle works in a static pose, such as an asana or other isometric contraction. The term can refer to the sarcomere length or to the angle in a covered joint.

Working range

The section of the ROM relating to a movement that is used for a cyclical movement or repetitions of an exercise. The movement can be a one-dimensional movement or one in a combination of several movement dimensions. There are always (usually, but not always: soft) movement limits that define an interval or a set, which is referred to as ROM for this movement. The working range is the subset of the ROM used in the exercise. The term can refer to the interval of sarcomere length or to the angular interval in an spanned joint.