Muscles of the forearm. According to the topographic location, the muscles of the forearm are divided into anterior and posterior groups, with four muscle layers in the front group, and two layers of muscles in the back.
Depending on the function performed, the muscles of the anterior group are divided into the flexors of the hand and fingers, and the back muscles into the extensors of the hand, fingers and instep supports.
The anterior group of muscles of the forearm (Fig. 72, A, B). 1. The first (superficial) layer of the muscles of the forearm. Brachioradialis muscle(m. brachioradialis) has a fleshy beginning from the humerus, lateral intermuscular septum and is attached to the distal end of the radius. Flexes the forearm at the elbow joint, rotates the radius, is set in the middle position between pronation and supination.
Round pronator(m. pronator teres) starts from the medial epicondyle of the humerus and the coronoid process of the ulna; attaches to the middle part of the radius. Participates in flexion of the forearm, turns it towards the elbow (pronation).
Radial flexor of the wrist(m. flexor carpi radialis) originates from the inner epicondyle of the humerus, from the fascia of the forearm and is attached to the base of the second metacarpal bone. Flexes the wrist, participates in the pronation of the hand.
The long palmar muscle (i.e. palmaris longus) starts from the inner epicondyle of the humerus, the fascia of the forearm and attaches to the palmar aponeurosis. Participates in flexion of the hand, strains the palmar aponeurosis.
Elbow wrist flexor(m. flexor carpi ulnaris) begins with the humeral head from the inner epicondyle of the humerus and fascia, the ulnar head from the ulna and attaches to the pisiform, uncinate and V metacarpal bones. Flexes the wrist, brings the wrist.

Rice. 72.
A - superficial: 1 - aponeurosis of the biceps brachii; 2 - biceps muscle of the shoulder; 3 - round pronator; 4 - long palmar muscle; 5 - elbow flexor of the wrist; 6- shoulder-tevaya head of the superficial flexor of the fingers; 7- superficial flexor of the fingers; 8 - short palmar muscle; 9 - square pronator; 10 - the radial head of the superficial flexor of the fingers; 11 - long radial extensor of the wrist; 12 - radial flexor of the wrist; 13- brachioradial muscle; B - deep: 1 - aponeurosis of the biceps brachii; 2 - deep flexor of the fingers; 3, 6 - superficial flexor of the fingers; 4 - square pronator; 5 - long flexor of the thumb; 7- instep support; 8- biceps brachii

2. The second layer of the muscles of the forearm. Superficial finger flexor(m. flexor digitorum superflcialis) originates from the medial epicondyle of the humerus, the coronoid process of the ulna, the proximal radius; ends with the attachment to the middle phalanges of the II-V fingers of the bone. Participates in the flexion of the middle phalanges of the II-V fingers, in the flexion of the hand.
3. The third layer of the muscles of the forearm. Deep finger flexor(m. flexor digitorum profundus) originates from the upper two-thirds of the anterior surface of the ulna and the interosseous membrane of the forearm; attached to the base of the distal phalanges of the II-V fingers. Flexes the distal phalanges of the II-V fingers and the hand.
Long flexor of the thumb(m. flexor pollicis longus) starts from the anterior surface of the radius and is attached to the distal phalanx of the thumb. Flexes the distal phalanx of the thumb and hand.
4. The fourth (deep) layer of the muscles of the forearm. Square pronator(m. pronator quadratus) starts from the anterior edge and the anterior surface of the lower third of the ulna and radius, attaches to the anterior surface of the distal third of the radius. Turns inward (penetrates) the forearm and hand.
The back muscle group of the forearm. 1. The superficial layer of the muscles of the forearm. Long radial extensor of the wrist(m. extensor carpi radialis longus) originates from the lateral epicondyle of the humerus, the lateral intermuscular septum of the shoulder; attached to the base of the II metacarpal bone. He flexes the forearm somewhat, unbends the hand, removes the hand laterally.
Short radial extensor of the wrist(m. extensor carpi radialis brevis) starts from the lateral epicondyle of the humerus and fascia of the forearm; attached to the dorsum of the base of the third metacarpal bone. Extends the brush and pulls it away.
Finger extensor(m. extensor digitorum) begins on the lateral epicondyle of the humerus and fascia of the forearm. The muscle is divided into four tendons, which on the back of the hand pass into tendon extensions and are attached to the base of the distal phalanx of the II-V fingers.
Little finger extensor(m. extensor digiti minimi) originates from the lateral epicondyle of the humerus and attaches to the middle and distal phalanx of the little finger. Extends V finger.
Elbow wrist extensor(m. extensor carpi ulnaris) starts from the lateral epicondyle of the humerus, fascia of the forearm. Attaches to the base of the V metacarpal bone. Extends and brings the brush.
2. The deep layer of the muscles of the forearm. Instep support(m. supinator) starts from the lateral epicondyle of the humerus, the capsule of the elbow joint, the crest of the instep support of the ulna; attaches to the lateral surface of the proximal third of the radius. Turns (su-pines) outwardly the radius and hand.
The long muscle abducting the thumb of the hand(m. abductor pollicis longus) begins on the back surface of the ulna and radius, the interosseous membrane of the forearm; attached to the base of the I metacarpal bone. Removes the thumb and the entire hand.
Short extensor of the thumb(m. extensor pollicis brevis) departs from the posterior surface of the radius, the interosseous membrane of the forearm; attached to the base of the proximal phalanx of the thumb. Extends the proximal phalanx, removes the thumb of the hand.
Long extensor of the thumb of the hand(m. extensor pollicis longus) originates from the back surface of the ulna, interosseous membrane; attached to the base of the distal phalanx of the thumb. Extends the thumb of the hand.
Extension of the index finger(m. extensor indicis) begins on the back surface of the ulna, the interosseous membrane of the forearm; attached to the dorsum of the proximal phalanx of the index finger. Extends the index finger.

The anterior forearm muscles (flexors) are arranged in 4 layers. The muscles are examined sequentially from the side of the radius towards the ulna. The first, superficial layer is formed by the following muscles: brachioradialis muscle, elbow flexor of the wrist. In the second layer lies the superficial flexor of the fingers. The third layer is formed by two muscles: the long flexor of the thumb (on the radial side, the deep flexor of the fingers (on the ulnar side). The deepest, fourth, layer is represented by a square pronator.

First (superficial) removal of the forearm muscles

The brachioradialis muscle (m.brachioradialis) has a fleshy beginning on the lateral supracondylar crest of the humerus and on the lateral intermuscular septum. At the level of the middle of the forearm, the muscular abdomen continues into a narrow flat tendon that passes under the tendons of the abductor longus muscle and the short extensor muscle of the thumb of the hand and attaches to the lateral surface of the distal end of the radius. The brachioradialis muscle limits the ulnar fossa from the lateral side.

Function: flexes the forearm at the elbow joint, rotates the radius, sets the hand in an average position between pronation and supination.

Innervation: radial nerve (CV-CVIII).

Blood supply: radial artery, collateral and recurrent radial arteries.

Round pronator

(m.pronator teres) - the shortest of the muscles of the superficial layer. At the site of the beginning, it is divided into two unequal parts, the largest of which begins on the medial epicondyle of the shoulder, the fascia of the forearm, the medial intermuscular septum, and on the fascia plate that separates the muscle from the radial flexor of the wrist. The smaller part originates deeper - on the coronoid process of the ulna. The median nerve runs between these two parts of the pronator circular. The muscle follows in the distal direction and outward, limiting the ulnar fossa from the lower medial side. The muscle is attached by a flat tendon in the middle of the lateral surface of the radius.

Function: acting on the proximal and distal radioulnar joints, it turns the forearm together with the hand to the elbow side (pronation), also participates in flexion of the forearm in the elbow joint.

The radial flexor of the wrist (m.flexor carpi radialis) begins on the medial condyle of the shoulder, on the fascia and the medial intermuscular septum of the shoulder. Approximately in the middle of the forearm, the muscle continues into a flat long tendon, which, passing under the flexor retinaculum (retinaculum flexorum) in the groove on the trapezium bone, attaches to the base of the II (partially III) metacarpal bone.

Function: flexes the wrist, acting together with the radial extensor of the hand, pulls the hand laterally.

Innervation: median nerve (CV-ThI).

Blood supply: brachial, ulnar and radial arteries.

The long palmar muscle (m.palmaris longus) begins on the medial epicondyle of the shoulder, on the fascia and adjacent intermuscular septa of the forearm. It has a short, fusiform, muscular abdomen, which in the middle of the forearm becomes a flat long tendon. The tendon extends to the hand above the flexor retinaculum and is woven into the proximal frankincense aponeurosis. Sometimes the muscle is missing.

Function: tightens the palmar aponeurosis, at the same time participates in flexion of the hand.

Innervation: median nerve (CV-ThI).

Blood supply: radial artery.

Elbow wrist flexor

(m.flexor carpi ulnaris) begins with two heads - shoulder and ulnar. The brachial head (caput brachiale) originates on the medial epicondyle and on the medial intermuscular septum of the shoulder. The ulnar head (caput ulnare) begins deeper - on a deep leaf of the fascia of the forearm, on the medial edge of the olecranon and the posterior edge of the ulna.

In the region of the proximal third of the forearm, both heads are connected to a common abdomen. Further, the muscle is directed to the palmar surface of the hand along the medial edge of the forearm and passes into a long tendon, which is attached to the pisiform bone. Part of the tendon bundles continues below, forming the piso-hook-shaped ligament, and attaches to the hook of the uncinate bone and the piso-metacarpal ligament, as well as to the base of the V metacarpal bone.

Function: flexes the wrist (in conjunction with the radial wrist flexor); while contracting with the ulnar extensor of the wrist, brings the hand.

Innervation: ulnar nerve (CVII-CVIII).

Blood supply: ulnar artery, superior and inferior collateral ulnar arteries.

The second layer of the muscles of the forearm

The superficial flexor of the fingers (m.flexor digitorum superficialis) begins with two heads - brachio-ulnar and radial. The heads are connected in the form of a bridge by a tendon stretch that crosses the median nerve and ulnar blood vessels in front.

The shoulder head (caput humeroulnare) is larger than the radial head. It begins at the medial epicondyle of the shoulder, fascia of the forearm, ulnar collateral ligament, and at the medial edge of the coronoid process of the ulna. The smaller one - the radial head (caput radiale) - begins on the proximal two-thirds of the anterior edge of the radius. In the proximal forearm, both heads join and form a common abdomen of the muscle, which is divided into 4 parts in the middle of the forearm, and in the distal third of the forearm passing into tendons. These tendons, passing along with the deep flexor tendons of the fingers through the wrist canal (under the flexor retinaculum and the palmar aponeurosis), are directed to the palmar surface of the II-V fingers and are attached to the base of the middle phalanges.

At the midpoint of the proximal phalanx, each superficial finger flexor tendon splits into two legs, between which the corresponding deep finger flexor tendon passes.

Function: flexes the middle phalanges of the II-V fingers (along with the fingers themselves), participates in flexion of the hand.

Innervation: median nerve (CV-ThI).

Blood supply: radial and ulnar arteries.

The third layer of the muscles of the forearm

The deep flexor of the fingers (m.flexor digitorum profundus) begins on the proximal two-thirds of the anterior surface of the ulna and on the interosseous membrane of the forearm. The four tendons of the muscle, along with the tendons of the superficial finger flexor, pass through the canal of the wrist. At the level of the proximal phalanges, the deep flexor tendons of the fingers pass between the split tendons of the superficial flexor of the fingers and attach to the bases of the distal phalanges of the II-V fingers.

Function: bends the distal phalanges of the II-V fingers (along with the fingers themselves); participates in flexion of the wrist in the wrist joint.

Innervation: ulnar and median nerves (CV-ThI).

Blood supply: ulnar and radial arteries.

The long flexor of the thumb of the hand (m.flexor pollicis longus) begins on the anterior surface of the radius and the adjacent part of the interosseous membrane of the forearm from the level of the tuberosity of the radius to the upper edge of the square pronator. The muscle tendon runs through the carpal tunnel into a separate synovial sheath. In the palm of the hand, it passes between the two heads of the short flexor of the thumb of the hand and attaches to the base of the distal phalanx of the thumb.

Function: flexes the distal phalanx of the thumb of the hand (along with it the finger itself), participates in flexion of the hand.

Innervation: median nerve (CV-ThI).

The fourth layer of the muscles of the forearm

The square pronator (m.pronator quadratus) is a flat muscle with transversely oriented bundles of fibers. It is located under the flexor tendons of the fingers and wrist on the front surface of the lower third of the body of the ulna, radius and on the interosseous membrane of the forearm. The muscle begins at the anterior edge and anterior surface of the lower third of the ulna body. Having passed in the transverse direction, the muscle attaches to the anterior surface of the distal third of the radial body.

Function: penetrates the forearm and hand.

Innervation: median nerve (CV-ThI).

Blood supply: anterior interosseous artery.

Posterior forearm muscle group

The back muscles of the forearm are divided into superficial and deep layers. The superficial layer includes 5 muscles: the long radial extensor of the wrist, the short radial extensor of the wrist, the extensor of the fingers, the extensor of the little finger, the ulnar extensor of the wrist. The deep layer is also formed by 5 muscles: an instep support, a long muscle that abducts the thumb of the hand, a long extensor of the thumb of the hand, and an extensor of the index finger.

The superficial layer of the muscles of the forearm

The long radial extensor of the wrist (m.extensor carpi radialis longus) begins with muscle bundles on the lateral epicondyle of the humerus and the lateral intermuscular septum of the shoulder. Here, the muscle is directly adjacent to the lateral surface of the capsule of the elbow joint. Distally, along the entire length of the forearm, the muscle occupies the gap between the brachioradialis muscle (front) and the short extensor of the wrist (back). In the middle of the forearm, the muscle passes into a flat tendon, which, passing under the retinaculum extensorum, attaches to the base of the second metacarpal bone.

Function: flexes the forearm (slightly), unbends the hand; while contracting with the radial flexor of the wrist, it abducts the hand laterally.

Blood supply: radial artery, collateral radial and recurrent radial arteries.

The short radial extensor of the wrist (m.extensor carpi radialis brevis) begins on the lateral epicondyle of the humerus, radial collateral ligament, on the fascia of the forearm. Attaches to the dorsum of the base of the third metacarpal bone.

Function: unbends the brush; while contracting together with the radial flexor of the wrist, it abducts the hand.

Innervation: radial nerve (CV-CVIII).

Blood supply: collateral radial and recurrent radial arteries.

Finger extensor

(m.extensor digitorum) is located medial to the radial extensors, begins on the lateral epicondyle of the humerus and on the fascia of the forearm. Near the wrist joint, it is divided into 4 tendons, which pass under the extensor retainer in the common synovial sheath and are attached to the back of the II-V fingers, forming tendon extensions. The middle bundles of tendon extension are attached to the base of the middle phalanx, and the lateral ones to the distal phalanx. At the level of the metacarpal bones, the extensor tendons of the fingers are connected to each other by obliquely oriented fibrous bundles - the connexus intertendineus.

Function, unbends II-V fingers; participates in the extension of the hand in the wrist joint.

Innervation: radial nerve (CV-CVIII).

The extensor of the little finger (m.extensor digiti minimi) has a common origin with the extensor of the fingers. The thin tendon of this muscle passes under the extensor retinaculum in a separate synovial sheath and is attached on the back of the little finger to the bases of its middle and distal phalanges (muscle tendon bundles are spliced ​​with the extensor tendon of the fingers).

Function: unbends the little finger.

Innervation: radial nerve (CV-CVIII).

Blood supply: posterior interosseous artery.

The extensor carpus ulnar (m.extensor carpi ulnaris) begins on the lateral epicondyle of the humerus, the capsule of the elbow joint, and the fascia of the forearm. Attaches to the base of the V metacarpal bone. The muscle tendon runs separately in the synovial sheath under the extensor retainer, occupying a groove on the posterior surface of the distal end of the ulna.

Function: unbends the brush. Acting in conjunction with the elbow flexor of the wrist, leads the hand.

Blood supply: posterior interosseous artery.

Deep layer of the muscles of the forearm

The instep support (m.supinator) is almost completely covered with superficial muscles. The instep support begins on the lateral epicondyle of the humerus, radial collateral ligament, on the annular ligament of the radial bone and the crest of the instep support on the ulna.

The muscle runs obliquely in the lateral direction (covers the radius from behind and from the side) and attaches to the lateral surface of the proximal third of the radius.

Function: turns outwardly (instep support) the radius along with the hand.

Innervation: radial nerve (CVI-CVIII).

Blood supply: radial, recurrent and interosseous arteries.

The long muscle that abducts the thumb of the hand (m.abductor pollicis longus) begins on the back of the ulna, the back of the radius and on the interosseous membrane of the forearm. Following from the place of its origin downward and laterally, the muscle bends around the outside of the radius with the tendons of the radial extensors of the wrist lying on it. Further, the tendon of this muscle passes along with the tendon of the short extensor of the thumb of the hand in one synovial sheath under the lateral part of the extensor retinaculum and attaches to the dorsum of the base of the I metacarpal bone.

Function: removes the thumb of the hand; participates in the abduction of the hand.

Innervation: radial nerve (CV-CVIII).

Short extensor of the thumb

(m.extensor pollicis brevis) is present only in humans (genetically it is part of the long muscle that abducts the thumb of the hand). It begins on the posterior surface of the radius, on the interosseous membrane of the forearm. The tendon of this muscle passes along with the tendon of the abductor thumb muscle in one synovial sheath under the extensor retinaculum. Attaches to the base of the proximal thumb phalanx.

Function: unbends the proximal phalanx (along with it the finger), removes the thumb of the hand.

Innervation: radial nerve (CV-CVIII).

Blood supply: radial artery, posterior interosseous artery.

The long extensor of the thumb (m.extensor pollicis longus) begins on the lateral side of the posterior surface of the ulna (within its middle third), on the interosseous membrane of the forearm. The extensor longus tendon of the thumb of the hand passes under the extensor retinaculum in a separate synovial sheath, in the groove on the posterior surface of the radius. Attaches to the base of the distal phalanx of the thumb.

Function: extends the thumb of the hand.

Innervation: radial nerve (CV-CVIII).

Blood supply: radial artery, posterior interosseous artery.

The extensor of the index finger (m.extensor indicis) begins on the back of the ulna and on the interosseous membrane of the forearm. The muscle tendon runs along with the extensor tendons of the fingers in the common synovial sheath under the extensor retinaculum. Attaches to the posterior surface of the proximal phalanx of the index finger (the muscle tendon is spliced ​​with the extensor tendon bundles).

Function: extends the index finger.

Hey! The hardest part of studying bones is, of course, the temporal bone. The hardest part of the peripheral nervous system is the cranial nerves. But the hardest part of myology in normal anatomy is the forearm, this is undeniable. The forearm amazes students in a lecture, sometimes there is simply no idea how all this is possible to learn.

But it is possible to learn it, and very quickly. The main thing is to arrange memorizing landmarks and clearly imagine the entire anatomical picture as a whole.

First of all, let's remember that the hand should only be viewed in a physiological position. We will have a large number of schemes ahead, at your seminars you will also answer on tablets and drugs - so, everywhere, absolutely everywhere, hands are in the correct physiological position. That is, the inner side of the palm is forward, and the nails are back. Like this illustration:

And one more thing that is important for us. All that is on the arm in the physiological position in front are the flexors. Everything in the back is the extensors. When we pull up with a reverse grip, the biceps work, and he is in front. When we bring our palm closer to the shoulder, bending the arm at the elbow joint, we use the biceps. It's the same with the forearm - there are flexor muscles in front, let's start with them.

MUSCLES OF THE FOREAR, ANTERIOR GROUP:

Surface layer.

1. Our main landmark here is a powerful, large brachioradialis muscle(musculus brachioradialis). Its special features: it is very wide, powerful, against the background of other muscles. It occupies the most lateral position (if the hand is physiologically positioned).

Do not forget that the radius goes from the elbow joint to the wrist along the side of the thumb. This is how we show the brachialis muscle. The largest, the most lateral is just a fairy tale. Unambiguously the main landmark, which is immediately visible on any tablet or preparation.

• Location: starts from the humerus, attaches to the radius (it's easy to remember by the name);
• Function: very typical for this entire muscle group. Namely - flexion of the arm at the elbow joint.

2. Round pronator(musculus pronator teres). Using our first reference point, we can easily identify the round pronator (in what place is the round truth, a question for the ancient anatomists). It is he with the brachioradialis, the widest and most lateral muscle, that forms the letter Y. It is very easy to remember.

• Location: starts from the medial epicondyle of the humerus, as well as from the coronoid process of the ulna (the muscle is rather wide and short). Attaches to the center of the radius from the lateral side.
• Function: flexion of the arm at the elbow joint and also penetrates the forearm.

By the way, there is a great way to remember what suppination and pronation are. Imagine you are carrying a bowl of soup. If your palm is in the same position as holding a bowl of SOUP, it is Supported. If you turn the palm over, the soup Spills and Pronation occurs.

3. We remembered this Y, which is formed by our main reference point - the brachioradialis muscle (the most lateral, very large) and the round pronator, which is adjacent to it at an acute angle. But the round pronator fits very tightly radial wrist flexor(musculus flexor carpi radialis). Of course, it does not look very laterally, but we will have another flexor, relative to which the radial flexor of the wrist will be really lateral.

• Location: starts from the medial epicondyle of the humerus, attaches to the second metacarpal bone.
• Function: As the name suggests, this muscle flexes the wrist

4. We are talking about this muscle - elbow wrist flexor(musculus flexor carpi ulnaris). It is the most medial muscle of the superficial layer of the anterior group. Longest, thinnest and most medial. Pretty simple, isn't it?

• Location: It starts from the already familiar medial epicondyle of the humerus, as well as from the back surface of the ulna (the muscle has two heads). Attaches to the uncinate bone.
• Function: bends the brush

5. So, we have two flexors - radial and ulnar. And between them will pass long palmar muscle(musculus palmaris longus). I deliberately chose to leave the radial and ulnar flexors tinted because they are great landmarks for locating the palmaris longus. I marked the longest palmar muscle with a red dotted line.

An important feature of the long palmar muscle is that it is woven into the wide palmar aponeurosis. You can find the palmaris longus on the specimen by first finding the aponeurosis itself, and then looking a little more proximally - the elongated palmaris longus tendon.

• Location: starts from the medial epicondyle of the humerus, attaches, as we have already found out, to the wide palmar aponeurosis.
• Function: bends the brush. Do not confuse it, it is the hand that flexes this muscle, not the palm.

So, what will help us remember all this, what are the loopholes, life hacks and patterns in this topic?

1. Correct landmarks... We start from the brachioradialis muscle. A very large, most lateral muscle of the entire group. Then we find the round pronator - the same muscle that connects to the brachioradial in the shape of the letter Y. Then we find two flexors - the radial and ulnar. Between them (also an excellent landmark, by the way) runs the long palmar muscle with a very characteristic direction straight to the center of the palm, to the palmar aponeurosis.
2. Names... Pronator - pronate, wrist flexors, oddly enough, flex the wrists. Three out of five muscles have a function - in the name.
3. Regularity of location... All muscles, except for the brachioradialis, start from the medal epicondyle of the humerus.

Lexical minimum.

A traditional list of Latin names for muscles that you should display on tablets without any problems, as well as explain their function and location:

• Musculus brachioradialis;
• Musculus pronator teres;
• Musculus flexor carpi radialis;
• Musculus flexor carpi ulnaris;
• Musculus palmaris longus

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 skinny state.

Forearm- this is the part of the hand that is located between the ELBOW and the WRIST.

This is because our forearms are made up of a HUGE amount of small muscles.

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

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

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

After all, when you do squats, you are doing them to develop your quads, hamstrings and glutes, and not in order to pump up the adductors.

This is true from the point of view of the cost of the training process and obtaining the corresponding result.

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

Movements performed by the muscles of the forearm

All movements performed by the muscles of the forearm can be divided into FIVE CATEGORIES:

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

It is important to consider the Forearm Bones, because their structure allows us to move in different vectors, which means we can use different exercises.

Inside the wrist there is not one, but TWO IMPORTANT BONES - RADIAL and ELBOW, which are connected with 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 extra 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, c.

Forearm muscles: anatomy

The muscles of the forearms are a very intricate chain of many different muscles.

I must say that most of these muscles simply supplement the work of one main muscle, and, as you can imagine, these "secondary muscles" synergists give less gain in volume.

Therefore, we will develop with you exactly those muscles that are best susceptible to growth.

1. Brachioradialis muscle(from the English "brachiordialis") - this is the BIGGEST muscle of the forearms. She bends the forearm, and also, takes part in pronation and supination of the forearm (rotates the forearm in and out). When flexing the arms with a reverse grip (grip from above), the brachioradialis muscle is SECOND in importance after the brachialis muscle.
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 function is basic. 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 (towards the elbow). Those. unbends the wrist in the wrist joint.
4. Round pronator brush - this muscle is located on the “lower levels 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 (towards the little finger). Additional function: flexion of the forearm.
5. Square pronator brush - 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 edge of the forearm.
6. Brush arch support - rotates the forearm outward (supine) and is included in the work when the arm is extended at the elbow joint. The instep is located deeper than the pronator and crosses it crosswise on the other side, i.e. attaches 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 little volume from them, but we will also talk about them.
8. Shoulder muscle (brachialis) - we talked about it in the article about. It does not apply to the muscles of the forearms, but in all flexion movements with a pronated hand ("hammer", "lifting the bar for biceps with a reverse grip", etc.) does most of the work. These flexion exercises are important to do because they are the main exercises for developing the brachioradialis muscle (which is the bulk of the forearms.

Tip: Train your forearms on biceps training days, otherwise, if you do flexions on another day, your forearms are at risk of overloading.

Tip: Train your forearms AT THE END of your basic workout. The forearms are the link in all pulling movements. If you “hammer” your forearms at the start of your workout, you will not be able to properly load the rest of the muscle groups.

In the near future, friends, there will be an article about the most detailed forearm training schemes. I am sure many of you will be very interested.

P.S. Subscribe to blog updates... It will only get steeper from now on.

Regards and best wishes!