If you bend your hand palm up at a right angle at the elbow so that the hand experiences strong resistance, you can see that the muscles of the forearm consist of two arrays (see Fig. 38). One array is internal: its muscles mainly start from the internal epicondyle of the shoulder and stretch to the palm. Another array is external: its muscles start mainly from the external epicondyle and stretch to the back of the hand. The border between these arrays from the rear is the ulna - it can be felt all the way from top to bottom, and from the palmar side - the ulnar (muscular) fossa, into the depths of which the tendon of the biceps muscle of the shoulder goes.

The muscles of the forearm mainly move the hand and fingers. Their muscular parts are located on the forearm, and downwards they pass into the tendons that stretch to the hand. From this, the forearm is expanded at the top, and narrowed at the bottom. The tendons of the muscles that move the fingers are attached to the phalanges, and the tendons of the muscles that move the hand, with the exception of two, are attached to the metacarpal bones. The muscles of the internal array are mainly flexors, the muscles of the external array are extensors.

1 The flexor group (Fig. 38, 39) consists of superficial and deep muscles. The superficial muscles include the pronator teres, the radial flexor of the hand, the long palmar muscle, the ulnar flexor of the hand.

Round pronator. It stretches obliquely from the inner epicondyle to the radius, bends around it and attaches to it in such a way that, contracting, it turns the radius together with the hand palm down - it penetrates and flexes the forearm.

Radial flexor of the hand (wrist). Lies next to the pronator. Its tendon goes obliquely and is attached to the base of the second metacarpal bone.

Action. Bends the hand, tilting it towards the beam (i.e. towards the thumb).

Long palmar muscle. It lies next to the previous one, the tendon goes to the middle of the palm and is woven into the palmar aponeurosis.

Action. Bends the brush straight.

Elbow flexor of the hand (wrist). Flat, very wide, with one edge adjacent to the long palmar muscle, the other - to the ulna

Rice. 39. Muscles of the forearm (right). BUT - palmar surface:

1 - biceps muscle of the shoulder, 2 - shoulder muscle, 3 - tendon of the biceps muscle, 4 - Pirogov fascia, 5 - long radial extensor of the hand, 6 - shoulder muscle. 7 - short radial extensor of the hand. 8 - radial flexor of the hand. 9 - long palmar muscle. 0 - short extensor and long abductor of the thumb, // - muscle elevation of the thumb! finger, 12 - palmar aponeurosis, 13 - tendon of the long flexor of the thumb. 14 - tendons of the deep flexor of the fingers, / 5 tendons of the superficial flexor of the fingers, 16- muscle elevation of the little finger, 17 - pisiform bone, 18 - transverse carpal ligament.. 19 - superficial finger flexor. 20 - ulnar flexor of the hand, 21- round pronator, 22 - internal condyle of the shoulder. 23 - shoulder muscle, 24 - triceps;

B - outside surface:

1 - triceps muscle of the shoulder. 2 - olecranon. 3 - external condyle of the shoulder, 4 - elbow! muscle. 5 - ulnar extensor of the hand. 5 - common extensor of the fingers, 7 - head of the ulna. 8 - attachment of the tendons of the radial extensor of the hand, 9 - attachment of the tendon of the ulnar extensor of the hand, 10 - dorsal interosseous muscles, II- metacarpal heads 12- adipose tissue. 13 - tendon of the long extensor of the thumb. 14 - first dorsal interosseous muscle 15 - short extensor of the thumb, 16- long abductor muscle of the thumb. 17 - anatomical snuffbox. 18 - dorsal transverse ligament of the wrist. 19 - short radial extensor of the hand, 20- long radial extensor of the hand. 21 - shoulder muscle, 22 -shoulder muscle 23 - biceps muscle

bone from which it partly originates. Below it forms a short tendon, which is attached to the pisiform bone.

Action. Flexes the hand towards the ulna.

Bend the supinated hand without bending the fingers (Fig. 39); at the wrist, three tendons protruding under the skin are visible. If we consider them from the thumb to the little finger, then the tendon of the radial flexor lies first, then the long palmar muscle, and finally the tendon of the ulnar flexor. If, while maintaining the same position of the hand, bend the fingers (except for the thumb) so that the pads of the fingers are adjacent to the bottom of the palm, you can see that the tendons of the flexors of the hand remain motionless, and the muscle masses move behind them in depth - these are the deep muscles - flexors fingers; There are two of them: superficial and deep. Each is divided into four tendons, going to all fingers except the thumb; the tendons of the superficial flexor are attached to the II phalanges - in this case, this muscle is mainly reduced. With even greater flexion of the fingers with the bending of the nail phalanges inward, an additional contraction of the muscles of the forearm is visible - this is a contraction of the deep flexor of the fingers; its tendons are attached to the nail phalanges. Flexion of fingers is made completely.

2. Extensor group. The brachioradialis muscle (Fig. 38, 39) (not being an extensor, makes up a plastic whole with the extensors, therefore it is described together with them) starts from the outer edge of the humerus above the epicondyle, stretches down and attaches to the radius above its styloid process.

Action. Flexes the arm at the elbow and sets the forearm in a position intermediate between pronation and supination. Very embossed with intense flexion at the elbow (see Fig. 38).

The remaining muscles of this group, starting from the external epicondyle, bend around it so that on the arm straightened at the elbow they form a deepening-fossa of beauty, in which you can feel both the condyle and the head of the beam.

Long radial extensor of the hand. It has a short muscular belly (when stressed, it takes an ovoid shape) and a long tendon.

Short radial extensor. It has a spindle-shaped abdomen and a shorter tendon. The tendons of both muscles descend along the radius, pass below, as in a tunnel, between the bone and the muscles of the thumb that are thrown over them and are attached on the back of the hand to the bases of the II and III metacarpal bones (Fig. 39).

Action. Unbend the brush towards the beam (thumb).

Common extensor of the fingers. Lies next to the previous one. It is divided into four tendons, which pass to the back of the hand (where they are very prominent when extended) and are attached to the nail phalanges of the II-V fingers (Fig. 39).

Action. Extends these fingers.

The index finger (II) and the little finger (V) can freely unbend separately from the others (which is easy to see on your own hand). This is due to the presence of separate additional extensors of these fingers, which do not have a noticeable relief.

Elbow extensor of the hand. It stretches obliquely from the epicondyle between the previous and the ulnar muscle to the ulna and partly fuses with it. Its tendon is thrown from the head of the ulna to the hand, it is relief in this gap and is attached to the base of the fifth metacarpal bone (Fig. 39).

Action. Unbends the brush towards the elbow (little finger).

Elbow muscle. Triangular in shape, short, lies between the previous muscle and the ulna. It starts from the outer condyle of the shoulder, is attached to the upper part of the ulna.

Action. Extends the arm at the elbow.

Small supinator. It lies deep in the upper part of the forearm, has no plastic significance.

Action. Supinates the forearm and hand.

Muscles of the thumb. They lie apart (Fig. 39).

Abductor pollicis longus and extensor pollicis brevis. They begin in the depths of the forearm and appear on the surface from under the edge of the common extensor of the fingers. The first muscle lies above the second. They are bridged over the tendons of the radial extensor of the hand. Then they pass into the tendons, which, in the form of a common strand, are transferred from the radius, bypassing the wrist, to the base of the first metacarpal bone. The long abductor muscle is attached here, and the short extensor muscle reaches the 1st phalanx of the thumb, where it is attached.

Action. The names of the muscles clearly indicate their action. In addition, both muscles abduct the hand outward, while their muscular parts are embossed on the muscular arm, and above them, with a strong extension of the hand, a longitudinal depression is formed, since in this case the muscular part of the radial extensors is pulled upward.

Long extensor of the thumb (Fig. 39). It lies in depth, its tendon appears from under the edge of the common extensor of the fingers at the level of the wrist and passes to the nail phalanx of the thumb, where it is attached.

Action. Unbends the thumb, while the tendon is very prominent.

When the thumb is abducted and extended, the tendon of the long extensor and the common strand of the tendons of its other two muscles form a triangular fossa - an anatomical snuffbox, in the depth of which you can feel the styloid process of the radius, a large polygonal bone of the wrist and the base of the first metacarpal bone (see Fig. 39) .

Long flexor of the thumb (Fig. 39). Lies on the palmar surface of the radius, covered with other muscles; its tendon runs in depth to the 1st phalanx of the thumb. The muscle lies close to the skin on the palmar surface of the lower end of the radius, and here its contraction when the thumb is flexed is noticeable in the form of a small depression.

All the above muscle actions reproduce and check on the model and on your own hands.

Dorsal and palmar ligaments of the wrist. Strong transverse ligaments attached to the bones are bridged over the tendons of the muscles at the points of their transition from the forearm to the hand on the back and palmar sides and hold the tendons near the bones over which the tendons move. Above them, during flexion and extension, transverse skin folds are formed (Fig. 39).

Some muscles of the forearm move the brush other- fingers. The muscles that move the hand almost all bypass the wrist and are attached to the metacarpus, which makes it possible, with extensive movements of the hand, to bring the metacarpus to the forearm as close as possible (see Fig. 4, tables I, III) from one side of the joint, pushing the wrist to the opposite side, which is the reason for the change in the length of the hand (see the skeleton and movements of the hand, pp. 48, 49).

In addition, the muscles that move the hand are attached to it from different sides: the radial extensors - to the rear of the II and III metacarpal bones, the ulnar extensor - to the rear of the V metacarpal bone, the radial flexor - to the palmar side of the II metacarpal bone, the long palmar - to the middle palms, ulnar flexor - to the pea-shaped bone. Thanks to this, the muscles can move the hand in different directions and, in addition, while contracting, fix it in any position, and both fixation and these movements give complete freedom to the movements of the fingers. If you relax the muscles of the hand and chat in the air with your forearm, the hand will dangle like a rag (we make this movement when we dry wet hands), but the flabbiness of the hand instantly disappears, even if you continue to move the forearm, if you simultaneously strain all the muscles of the hand and thereby fix it .

With strong physical exertion (for example, when lifting weights), in addition to the work of the fingers, fixation of the hand is required. Therefore, in such cases, the muscles of the forearm are completely tense, which is reflected in their relief.

In work that does not require strong physical exertion, the hand and fingers are moved by the simultaneous tension of various muscles that move the hand and fingers. If these movements are complex, then they are not mastered immediately, but through exercises (as discussed above).

Analyze several working movements of the hand on the model and on yourself and be aware of which muscles move the hand and which move the fingers. Consider the change in the shape of the forearm during pronation and supination.

Questions. The two main mouse forearm arrays and their borders. Flexor group: pronator round, flexors of the hand, flexors of the fingers. Extensor group, brachioradialis and ulnar muscles. Muscles of the thumb Anatomical snuffbox. The action of the muscles that move the hand. The action of the muscles that move the fingers. their simultaneous action. Brush fixation.

The muscles of the forearm are divided into anterior and posterior groups. The anterior muscle group in function is flexors, the posterior one is extensors. The anterior muscle group is located in four layers, the back - in two layers.

Anterior group of muscles of the forearm. First layer

Shoulder muscle (t. brachioradialis) located on the lateral edge of the forearm, starts from the outer epicondyle of the humerus. Attached to the styloid process of the radius.

Function: flexes the forearm, rotates the radius.

Round pronator (t. pronator teres) begins with two heads: superficial - from the internal epicondyle of the humerus and deep - from the coronoid process of the ulna. Attached to the lateral surface of the radius.

Function: pronates the hand and flexes the forearm.

Radial wrist flexor (t. flexor carpi radialis) starts from the internal epicondyle of the humerus, passes into the tendon, which passes under the flexor retinaculum in the groove of the trapezoid bone and is attached to the base of the 2nd metacarpal bone.

Function: flexes the radial edge of the hand, takes part in the pronation of the hand.

Melon palmar muscle (t. palmaris longus) starts from the internal epicondyle of the humerus, passes into a thin tendon that passes over the flexor retinaculum and attaches to the palmar aponeurosis.

Function: strains the palmar aponeurosis, participates in flexion of the hand.

Elbow flexor of the wrist (t. flexor carpi ulnaris) starts from the inner epicondyle of the humerus, the fascia of the forearm (humeral head) and from the olecranon, the posterior edge of the ulna (ulnar head). Attaches to the pisiform bone.

Function: flexes the ulnar edge of the hand and somewhat supinates it.

Anterior group of muscles of the forearm. Second layer

Superficial flexor of the paws (t. flexor digitorum suprifi-cialis) starts from the internal epicondyle of the humerus, the coronoid process of the ulna and the middle third of the ulna. The muscle continues into four tendons for the 2nd-5th fingers. The tendons pass under the flexor retinaculum in the carpal tunnel to the hand and insert on the palmar surface of the middle phalanges. At the level of the proximal phalanx, each tendon of this muscle diverges into two legs and passes the tendon of the deep flexor of the fingers through the gap.

Function: flexes the middle phalanges of the 2nd-5th fingers, takes part in the flexion of the hand.

Anterior group of muscles of the forearm. third layer

Deep finger flexor (t. flexor digitorum profundus) starts from the anterior surface of the ulna and the interosseous membrane, is divided into four tendons, which pass in the carpal tunnel to the hand, pierce at the level of the proximal phalanges of the tendon of the superficial flexor of the fingers and attach to the distal phalanges of the 2nd-5th fingers.

Function: flexes the distal phalanges of the 2nd-5th fingers, takes part in the flexion of the hand.

D, flexor thumb (t. flexor pollicis longus) originates from the interosseous membrane and the anterior surface of the radius. The tendon passes through the carpal tunnel and inserts at the base of the distal phalanx of the thumb.

Function: flexes the distal phalanx of the thumb, takes part in the flexion of the hand.

Anterior group of muscles of the forearm. fourth layer

Square pronator (t. pronator quadratus) located in the lower third of the forearm, starts from the anterior surface of the ulna. Attached to the anterior and lateral surface of the radius.

Function: penetrates the forearm and hand.

Posterior muscle group of the forearm. Surface layer

D, extensor carpi radialis (m. extensor carpi radialis longus) originates from the lateral epicondyle of the humerus and the lateral intermuscular septum of the shoulder. Going down, it passes under the long muscle, which removes the thumb, and the short extensor of the thumb, the extensor retinaculum, and is attached to the base of the 2nd metacarpal bone.

Function: unbends the radial edge of the hand and takes part in flexion of the forearm at the elbow joint.

Short radial extensor of the wrist (t. extensor carpi radialis brevis) originates from the lateral epicondyle of the humerus. Attaches to the base of the 3rd metacarpal.

Function: unbends the brush.

Extensor of fingers (t. extensor digitorum) originates from the lateral epicondyle of the humerus and the fascia of the forearm. The muscular abdomen passes into four tendons, which pass under the extensor retinaculum and are attached to the bases of the middle phalanges of the 2nd-5th fingers.

Function: unbends the 2nd-5th fingers, participates in the extension of the hand.

Extensor of the little finger (t. extensor dfgiti minimi) starts next to the previous muscle. The tendon passes under the extensor retinaculum and inserts at the bases of the middle and distal phalanges of the little finger.

Function: extends the little finger.

Elbow extensor of the wrist (t. extensor carpi ulnaris) originates from the lateral epicondyle of the humerus and the fascia of the forearm. Attaches to the base of the 5th metacarpal.

Function: unbends the ulnar edge of the hand.

Posterior muscle group of the forearm. deep layer

Arch support muscle (t. supinator) starts from the lateral epicondyle of the humerus and the crest of the muscle - the supinator of the ulna. Attached to the outer surface of the upper third of the radius. Function: supinates the radius and hand.

The melon muscle that abducts the thumb of the hand (i.e. abductor pollicis longus), starts from the posterior surface of the radius and ulna, from the interosseous membrane. Attached to the base of the 1st metacarpal.

Function: abducts the 1st finger, participates in the abduction of the hand. Short extensor thumb (t. extensor pollicis brevis) begins next to the previous muscle from the interosseous membrane. Attaches to the base of the proximal phalanx of the thumb. Function: extends the thumb.

Dtnny extensor of the thumb (t. extensor pollicis longus) originates from the posterior surface of the ulna and the interosseous membrane of the forearm. Attaches to the base of the distal phalanx of the thumb, where it merges with the extensor brevis tendon. Function: extends the thumb of the hand.

Extensor of the index finger (t. extensor indicis) originates from the posterior surface of the ulna and the interosseous membrane of the forearm. Attaches to the proximal phalanx of the index finger, where it fuses with the extensor tendon of the fingers.

Function: extends the 2nd finger.

The muscles of the forearm, depending on the position, are divided into two groups: anterior and posterior, while each distinguishes between superficial and deep layers.

front group

Surface layer

1. Shoulder muscle (m. brachioradialis; see Fig. 77). Origin: humerus above lateral epicondyle, lateral intermuscular septum of brachial fascia; attachment: the lower end of the body of the radius.

Function: flexes the forearm, sets the hand in a position between pronation and supination.

2. Round pronator (m. pronator teres; see Fig. 77). Origin: medial epicondyle of the humerus, medial intermuscular septum of the brachial fascia, coronoid process of the ulna; insertion: middle third of the radius.

Function: pronates and flexes the forearm.

3. Radial flexor of the wrist (m. flexor carpi radialis; see Fig. 77). Origin: medial epicondyle of the humerus, fascia of the forearm; attachment: base of the II metacarpal bone.

Function: flexes and partially penetrates the hand.

4. Long palmar muscle (m. palmaris longus; see Fig. 77). Origin: medial epicondyle of the humerus, fascia of the forearm; attachment: palmar aponeurosis.

Function: strains the palmar aponeurosis, takes part in flexion of the hand.

5. The superficial flexor of the fingers (m. flexor digitorum superficialis; see Fig. 77) is wide, covered in front with the muscles described above. Origin: medial epicondyle of the humerus, ulna, proximal radius; attachment: the common muscular abdomen ends with four long tendons, which are each attached with two legs to the base of the middle phalanges of the II - V fingers of the hand.

Function: bends the middle phalanges of the II - V fingers.

6. Elbow flexor brush (m. flexor carpi ulnaris; see Fig. 77) has two heads. Beginning: humeral head - medial epicondyle of the humerus, fascia of the forearm; ulnar head - the olecranon and the upper two-thirds of the ulna; attachment: pisiform bone, part of the bundles through ligaments - to the hook-shaped and V metacarpal bones.

Function: flexes the hand and participates in its adduction.

deep layer

1. Long flexor of the thumb (m. flexor pollicis longus; see Fig. 77). Beginning: upper two-thirds of the anterior surface of the radius, interosseous membrane between the radius and ulna, partly from the medial epicondyle of the humerus; insertion: base of the distal phalanx of the thumb.

Function: flexes the distal phalanx of the first finger.

2. Deep finger flexor (m. flexor digitorum profundus; see Fig. 77). Origin: upper two-thirds of the anterior surface of the ulna, interosseous membrane; insertion: bases of the distal phalanges of II - V fingers.

Function: flexes the distal phalanges of the II-V fingers and the entire hand.

3. Square pronator (m. pronator quadratus; see Fig. 77) is located in the region of the distal ends of the bones of the forearm. Origin: medial edge of the body of the ulna; attachment: lateral edge and anterior surface of the radius.

Function: rotates the forearm inward.

back group

Surface layer

1. Long radial extensor of the wrist (m. extensor carpi radialis longus; Fig. 78). Origin: lateral intermuscular septum of the shoulder fascia, lateral epicondyle of the humerus; attachment: dorsal surface of the base of the II metacarpal bone.

Function: flexes the forearm, unbends and partly abducts the hand.

2. Short radial extensor of the wrist (m. extensor carpi radialis brevis; see Fig. 78). Origin: lateral epicondyle of the humerus, fascia of the forearm; attachment: dorsal surface of the base of the III metacarpal bone.

Function: unbends the brush.

3. Extensor of fingers (m. extensor digitorum; see Fig. 78). Origin: lateral epicondyle of the humerus, fascia of the forearm; attachment: the muscular abdomen continues into four tendons, which on the back of the hand pass into tendon extensions, each attached with its middle part to the base of the middle phalanx, and lateral to the base of the distal phalanx II - V fingers.

Function: unbends fingers and hand.

4. Extensor of the little finger (m. extensor digiti minimi; see Fig. 78). Origin: lateral epicondyle of the humerus; attachment: base of the distal phalanx of the fifth finger.

Function: extends the little finger.

5. Elbow extensor of the wrist (m. extensor carpi ulnaris; see Fig. 78). Origin: lateral epicondyle of the humerus, fascia of the forearm; insertion: base of the fifth metacarpal bone.

Function: unbends and leads the brush.

deep layer

1. Arch support (m. supinator; see Fig. 78). Origin: lateral epicondyle of the humerus, capsule of the elbow joint, crest of the supinator of the ulna; insertion: upper third of the radius from the anterior, lateral and posterior sides.

Function: rotates the forearm outward and takes part in the extension of the arm in the elbow joint.

2. A long muscle that removes the thumb of the hand (m. abductor pollicis longus; see Fig. 78). Origin: posterior surfaces of the ulna and radius, interosseous membrane; insertion: base of the 1st metacarpal bone.

Function: abducts the thumb and the entire hand.

3. Short extensor thumb brush (m. extensor pollicis brevis; see Fig. 78). Origin: posterior surface of the neck of the radius, interosseous membrane; insertion: base of the proximal phalanx of the thumb, capsule of the I metacarpophalangeal joint.

Function: abducts the thumb and extends its proximal phalanx.

4. Long extensor thumb brush (m. extensor pollicis longus; see Fig. 78). Origin: posterior surface of the body of the ulna, interosseous membrane; insertion: base of the distal phalanx of the thumb.

Function: unbends the thumb of the hand, partly abducts it.

5. Extensor of the index finger (m. extensor indicis; see Fig. 78). Origin: posterior surface of the body of the ulna, interosseous membrane; insertion: dorsal surface of the middle and distal phalanges of the index finger.

Function: extends the index finger.

Hello friends! Today we will look at the anatomy of the muscles of the forearm. The muscles of the forearm are most often exposed during the year, so it is not advisable for us to leave them in a dry state.

Forearm- This is the part of the arm that is between the ELBOW and the WRIST.

The fact is that our forearms are made up of a HUGE number of small muscles.

Nature did this so that we could perform various kinds of manipulations with the objects around us, and, just for this, you need to have very different mobility of the forearms, which is achieved only by a variety of muscles that perform these movements.

As usual, I only focus on the BIGGEST muscles in terms of size.

Why should we train those muscles that, in principle, give very little gain, both in terms of size and in terms of appearance?

After all, when you do squats, you're doing them to develop your quads, hamstrings, and glutes, not to build your adductors.

This is true in terms of the costs of the training process and getting the corresponding result.

That is why many beginners make the mistake of only starting to train biceps and abs as soon as they come to the gym. As a result, they get much less progress than those beginners who worked on their legs, chest and back in the first years of their training.

Movements performed by the muscles of the forearm

All movements that the muscles of the forearm perform can be divided into FIVE CATEGORIES:

• EXTENSION FOREARM(posterior muscle group, from the side of the triceps).
• flexion of the forearm(anterior muscle group, from the side of the biceps).
• SUPINATION of the forearm(muscles that rotate the forearm outward).
• PRONATION of the forearm(muscles that rotate the forearms inward).
• FOREARM CLUTCH(muscles that clench the fingers into a fist).

It is important to take into account the BONES OF THE FOREARM, because their structure allows us to move in different vectors, which means that we can use different exercises.

Inside the wrist, there is not one, but TWO IMPORTANT BONES - these are the RADIUS and ULNA, which are connected to each other by means of ligaments and muscles.

This anatomical structure makes it possible to move the radius around the ulna in a circle. This is the so-called. supination and pronation.

The muscles that perform these movements can be developed, so they will give additional volume to the forearms.

IMPORTANT: the muscles of the forearms are on “different floors”. Some of them are closer to the skin, and some are closer to the bones. We have already met with muscles that are located in several layers, in.

Muscles of the forearm: anatomy

The muscles of the forearms are a very tangled chain of a huge number of different muscles.

I must say that most of these muscles simply complement the work of one main muscle, and, as you understand, these "secondary muscles" synergists give a smaller increase in volume.

Therefore, we will develop exactly those muscles that will be best subject to growth.

1. brachioradialis muscle(from the English "brachiordialis") - this is the BIGGEST muscle of the forearms. It FLEXES the forearm and also takes part in pronation and supination of the forearm (rotates the forearms in and out). When bending the arms with a reverse grip (grip from above), the brachioradialis muscle is the SECOND in importance after the brachialis.
2. Flexors of the hand (radial and ulnar) - these muscles are located in the inner part of the forearms (from the side of the biceps) and are responsible for the movement of the hand towards the arm. This feature is the main one. Additional function: pronation of the hand (outward turn).
3. Radial extensor of the hand - this muscle is located on the side of the triceps, which extends the hand outward (toward the elbow). Those. extends the wrist at the wrist joint.
4. Round pronator brush - this muscle is located on the "lower floors of the forearms." It is attached next to the elbow from the side of the little finger, because its main task is to turn the wrists inward (toward the little finger). Additional function: flexion of the forearm.
5. Square pronator of the hand - performs movements similar to a round pronator. It differs in that it is a quadrangular plate, which is located next to the palm, i.e. from the other side of the forearm.
6. Hand support - rotates the forearm outward (supinates) and is included in the work when the arm is extended in the elbow joint. The arch support is located deeper than the pronator and crosses it on the other side, i.e. fastened from the elbow to the side of the thumb.
7. Flexors and extensors of the fingers - these muscles are located on the outside and on the inside of the forearm. Flexors are usually trained to have a strong grip. There is not much volume from them, but we will also talk about them.
8. Shoulder muscle (brachialis) - we talked about it in an article about. It does not apply to the muscles of the forearms, but in all flexion movements with a pronated hand (“hammer”, “lifting the barbell for biceps with a reverse grip”, etc.) does most of the work. These flexion exercises are important because they are the main exercises for the development of the brachioradialis muscle (it makes up the bulk of the forearms.

Tip: Train your forearms on bicep days, otherwise if you do curls on a different day, your forearms risk overstressing.

Tip: Train your forearms AT THE END of your main workout. The forearms are the link in all traction movements. If you overwork your forearms at the beginning of your workout, you won't be able to properly load the rest of your muscle groups.

In the near future, friends, an article will be published about the most detailed schemes for training forearms. I'm sure many of you will be very interested.

P.S. Subscribe to blog updates. It will only get worse from there.

With respect and best wishes, !