What are the pectoral muscles responsible for? Anatomy of the pectoral muscles, pectoralis major, pectoralis minor. Muscle training using a barbell

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proximal attachment. medial two-thirds of the clavicle; sternum, cartilaginous parts of the II-VII ribs, subcutaneous aponeuroses of the external oblique and rectus abdominis muscles.

Distal attachment. The crest of the greater tubercle of the humerus.

Function. Bringing the shoulder and rotating it inward. Clavicular portion: bending the arm as if trying to touch the opposite ear.

Palpation. The pectoralis major muscle forms the anterior wall of the armpit. Being a subcutaneous muscle of the chest, it is clearly visible when the patient presses medially on the iliac crest of the same side.

To localize the pectoralis major muscle, the following structures should be identified:

Collarbone. Trace the curved surface of the clavicle from its articulation with the sternum to its articulation with the acromion of the scapula. The medial part of the clavicle is convex, the lateral part is concave.

The sternum is a long, flat bone that forms the center of the anterior chest wall.

Intertubercular groove of the humerus. Locate the greater and lesser tuberosities of the humerus distal to the lateral surface of the acromion. (These formations are better palpated on the hand turned outward.) The intertubercular furrow is located medial to the large tubercle and lateral to the small one; the tendon of the long head of the biceps brachii muscle runs along it.

Locate the pectoralis major muscle of the patient in the supine position with the arm resting freely along the body. Palpate the muscle along its entire length, starting from the medial attachment to the sternum and to the medial two-thirds of the clavicle, move laterally along the chest wall towards the attachment of the muscle to the intertubercular groove. The free edge of the lateral surface of the pectoralis major muscle can be easily lifted above the chest wall with the help of a special “tweezer grip” technique for direct palpation of the fibers of this part of the muscle.

Pain pattern. Anterior side of the shoulder anterior to the deltoid muscle; the pain pattern may include the anterior chest and breast. The pain can spread along the ulnar side of the forearm to the 4th and 5th fingers. Sometimes pain can mimic an angina attack.

Causal or supporting factors.

Load stress when lifting a load in front of you; immobilization of the hand in the reduced position; prolonged reduction of the shoulders; prolonged anxiety, reflected pain in myocardial infarction by the mechanism of the viscerosomatic reflex.

satellite trigger points. Anterior deltoid, sternocleidomastoid, trapezius, rhomboid and scalene muscles.

Affected organ system. Respiratory and cardiovascular systems.

Associated zones, meridians and points.

ventral zone. Stomach Foot Meridian Yang Ming, Lung Hand Meridian Tai Yin, Spleen Foot Meridian Tai Yin, Kidney Foot Meridian Shao Yin. ST 14,15,16,18; LU 1,2,3; SP 19.20; KI 22-27.

Stretching exercises. Stand in front of a doorway and place your forearms firmly on either side of it.

Bend your body forward so that your shoulders are turned.

To stretch the upper fibers of the pectoralis major muscle, place the palms at about ear level.
. To stretch the middle fibers of the pectoralis major muscle, place your elbows at shoulder level.
. To stretch the lower fibers of the pectoralis major muscle, fully extend your arms and raise them above your head.

The chest muscles are one of the largest human muscle groups, which is located on the outer surface of the thoracic region. In their structure, they are fan-shaped and consist of 3 main muscle bundles.

The muscles of the chest can be divided into two structures.

The first includes muscle fibers that are directly related to the shoulder girdle:

- small muscle of the chest;

- a large muscle of the chest;

- toothed;

- subclavian muscle.

The pectoral muscles proper belong to the second:

- external intercostal muscles;

- internal intercostal muscles.

They are located in the intercostal spaces and are responsible for the contraction of the human diaphragm.

1. Large chest muscle has a powerful muscular structure and therefore occupies 90% of the chest. The main feature is their pairing and flatness. It is this structure that predisposes to the development of maximum hypertrophy of the muscle group.

Main functional features

The pectoralis major muscle is responsible for lowering the arm from the top position directly to the torso. At the same time, she makes a simultaneous turn of the hand to the inside of the body. A large lever allows you to make the above movement powerful, speedy and strong, which is exactly what is needed for heavy chest training.

2. Minor chest muscle in its shape it resembles a flat triangle and is located under the main muscle. It starts in the region of the ribs and is attached directly to the shoulder blade.

Main functional feature is aimed at moving the scapula and pulling it back and forth.

3. Front gear located on the side of the anterior part of the pectoral muscle, which starts from the ribs and is attached in the region of the scapula.

subclavian muscle located directly in the region of the collarbone.

Main functional activity the anterior muscle is aimed at turning and feeding the scapula forward. The second muscle has one function - it is the movement of the collarbone down.

4. Intercostal muscles There are two types: internal and external. They are attached to different parts of the ribs: this is necessary to ensure the normal process of exhalation and inhalation.

Subcostal muscles attached to the inside of the lower ribs. The main difference from the intercostal muscles is the uneven and rarer attachment of muscle bundles.

Diaphragm is a muscle structure responsible for human breathing. It is mobile, consisting of a septum, which is located between the cavities of the chest and abdomen.

Functional features:

When the diaphragm is brought into contraction, the plane of the chest moves away and increases, respectively, the abdominal one decreases. The above action is accompanied by a person's inhalation.

Contraction of the abdomen and diaphragm increases intra-abdominal pressure. This integral physiological characteristic is very important when working with extreme weights.

What should be noted from all of the above?

1. First, chest muscles are unique in their physiology and genetic predisposition to growth. The muscle fibers of the chest have an arrangement in different directions. That is why it is necessary to train the chest from different angles.

2. Secondly, the chest muscles are a large muscle group, so they are able to work in power mode and endure high-intensity training.

The muscles of the chest are divided into muscles that start on the surface of the chest and go from it to the belt of the upper limb and to the free upper limb, and into the own (autochthonous) muscles of the chest, which are part of the walls of the chest cavity.

In addition, we will describe here the thoracic obstruction (diaphragma), which limits the chest cavity from below and separates it from the abdominal cavity. The diaphragm in its origin belongs to the neck, so its innervation mainly comes from the cervical plexus (n. phrenicus).

I. Muscles of the chest related to the upper limb

1. M. pectoralis major, pectoralis major, starts from the medial half of the clavicle (pars clavicularis), from the anterior surface of the sternum and cartilage of the II-VII ribs (pars stemocostalis) and, finally, from the anterior wall of the sheath of the rectus abdominis muscle (pars abdominalis); attached to the crista tuberculi majoris of the humerus.
The lateral edge of the muscle is adjacent to the edge of the deltoid muscle of the shoulder, separated from it by a groove, sulcus, deltoideopectoralis, which expands upward under the clavicle, causing here a small subclavian fossa.
Function. Brings a hand to the body, turns it inward: (pronates); the clavicle flexes the arm. With fixed upper limbs, it can raise the ribs with the sternum and thereby promote inhalation, participates in pulling up the torso when climbing. (Inn. C5-8 Nn. pectorales medialis et lateralis.)

2. M. pectordlis minor, pectoralis minor, lies under the pectoralis major. It begins with four teeth from the II to V ribs and is attached to the processus coracoideus of the scapula.
Function. Pulls the scapula forward and down during its contraction. With fixed arms, it acts as an inspiratory muscle. (Inn. C7-8- Nn. pectorales medialis et lateralis.)

3. M. subclavius, subclavian muscle, stretches between the clavicle and the 1st rib.
Function. Strengthens the sternoclavicular joint by pulling the clavicle down and medially. (Inn. C4-6 N. subclavius.)

4. M. serratus anterior, serratus anterior, lies on the surface of the chest in the lateral region of the chest. The muscle usually begins with 9 teeth from the nine upper ribs and is attached to the medial edge of the scapula.
Function. Together with the rhomboid muscle, which is also attached to the medial edge of the scapula, it forms a wide muscle loop that covers the body and presses the scapula against it. When reducing entirely simultaneously with the dorsal muscles (rhomboid and trapezius) m. serratus anterior sets the scapula motionless, pulling it forward.
The lower part of the muscle rotates the lower angle of the scapula anteriorly and laterally, as happens when the arm is raised above the horizontal level. The upper teeth move the scapula together with the clavicle anteriorly, being antagonists of the middle fibers m. trapezius, with a fixed belt, raises the ribs, facilitating inhalation. (Inn. C5-7-N. thoracicus longus.)

Of the four muscles described, the first two are truncopetal, the second are truncofugal.

II. Autochthonous muscles of the chest.

1. mm. intercostales externi, external intercostal muscles, perform intercostal spaces from the spinal column to the costal cartilages. They start from the lower edge of each rib, go obliquely from top to bottom and back to front, and attach to the upper edge of the underlying rib. Between the cartilages of the ribs, the muscles are replaced by a fibrous plate with the same direction of fibers, membrana intercostalis externa. (Inn.Th1-11 Nn. intercostales.)

2. mm. intercostales interni, internal intercostal muscles, lie under the outer ones and, compared with the latter, have the opposite direction of the fibers, intersecting with them at an angle. Starting at the upper edge of the underlying rib, they go up and forward and attach to the overlying rib.
In contrast to the external, the internal intercostal muscles reach the sternum, located between the costal cartilages. In the direction of the back mm. intercostales interni reach only the corners of the ribs. Instead, between the posterior ends of the ribs is membrana intercostalis interna. Th1-12 Nn. intercostals.)

3. mm. subcostales, subcostal muscles, lie on the inner surface of the lower part of the chest in the area of \u200b\u200bthe corners of the ribs, have the same direction of fibers as that of the internal intercostal muscles, but are thrown over one or two ribs. (Inn. Nn. intercostales.)

4. M. transversus thoracis, transverse muscle of the chest, also located on the inner surface of the chest, in its anterior region, constituting a continuation of the transverse abdominal muscle. (Inn. Nn. intercostales.)
Function. mm. The intercostales externi produce rib cage elevation and anteroposterior and transverse expansion of the chest and are therefore inspiratory muscles active during normal quiet breathing.
With increased inhalation, other muscles also take part that can lift the ribs upward (mm. scaleni, m. sternocleidomastoideus, mm. pectorales major et minor, m. serratus anterior, etc.), provided that the mobile points of their attachments in other places were fixed motionless, as, for example, patients who suffer from shortness of breath instinctively do. The collapse of the chest during exhalation occurs mainly due to the elasticity of the lungs and the chest itself.

The pectoralis minor is the "smaller sister" of the more massive and well-known pectoralis major. However, even a muscle of such a small size can cause serious problems. It is located under the pectoralis major muscle, departs from the 3rd, 4th and 5th ribs, passes laterally upwards and is attached to the coracoid process of the scapula.

Functions of the pectoralis minor: stabilization of the scapula, as well as its lowering, pulling and turning down. When the scapula is in a fixed position, this muscle also takes part in lifting the chest. Explaining Functions pectoralis minor, the site will tell you what problems may be associated with it.

The condition of the pectoralis minor muscle and posture disorders

The pectoralis minor muscle is a fairly significant factor in the formation of correct (or incorrect) posture. One of the functions pectoralis minor is the retraction of the scapula - its movement forward, away from the spine, and around the chest, which leads to stoop in the shoulders.

Unfortunately, in the lives of most of us, a sedentary lifestyle prevails - we spend the lion's share of the time at computers, driving, leaning over a desk in unnatural positions, when our shoulders are rounded and tilted forward, our backs are hunched. This position over time inevitably leads to overstrain of the pectoralis minor muscle (the appearance of muscle knots, or clamps).

Posture disorders- although a big one, but not the only problem caused by overstrain of the pectoralis minor muscle. Because below the site will consider:

what are the symptoms and problems that appear with overexertion pectoralis minor;
What is pectoralis minor syndrome?
how to get rid of pain caused by overexertion of the pectoralis minor muscle.

Overexertion of the pectoralis minor muscle: the starting point of serious disorders

An overloaded pectoralis minor significantly affects the function of the shoulder joint and increases the risk of injury.

Perhaps the most common problem with pectoralis minor, is subacromial impingement syndrome.

In this case, the lack of space in the area between the humerus and the shoulder process (acromion) leads to pinching of the tendons of the supraspinatus muscle and subacromial bursa, especially when raising the arm above the shoulder, as well as during rotational movements.

Pinched tendons, nerves and blood vessels in the shoulder and chest area are the consequences of an overstrain of the pectoralis minor muscle.

This lack of space may be directly related to an overstretched pectoralis minor muscle due to forward tilt of the scapula and reduced subacromial arch.

In this case, patients complain about:

dull pain in the shoulder
increased pain when raising the arm up;
sleep problems as a result of pain, especially when lying on the affected side;
characteristic sound of a crunch or click while lowering the hand;
limitation of joint mobility;
hand weakness.

In addition to increasing the risk of pinching, overexertion of the pectoralis minor, together with the serratus anterior, verticalizes the glenoid fossa of the scapula, resulting in increased abduction, rotation, and pterygoidity of the scapula.

Due to a change in the position of the scapula, the muscle that lifts the scapula and the upper fibers trapezius muscle begin to strain intensely in an attempt to stabilize her position. Ultimately, this leads to overstrain of the muscles of the neck and shoulders and the appearance of many trigger points in this area, which is typical for many working at the table (well, or on the couch, with a laptop on their laps).

Pain in the shoulder, numbness of the arm, tingling in the upper limbs, as well as trigger points of the muscles of the neck and back are the consequences of overexertion of the pectoralis minor muscle.

Pectoralis minor syndrome - when nerves and blood vessels are affected

In 50% of cases, it is the pectoralis minor muscle that is the root cause of chest outlet compression syndrome (or simply pectoralis minor syndrome). What it is?

Pectoralis minor syndrome is manifested by compression of the nerves and blood vessels located in the anterior part of the shoulder and chest - the brachial plexus, subclavian artery and vein. Pinched nerves and blood vessels are sure to make themselves felt, causing significant physical discomfort.

Symptoms of this syndrome vary depending on the location and degree of compression of the neurovascular bundle and can manifest as:

pain throughout the arm - from the shoulder to the little finger;
numbness, decreased sensitivity, tingling in the limbs;
weakness in the arm;
blanching of the upper limb;
decrease in hand temperature;
increased pain during movement.

As you can see, the small pectoral muscle, or rather, its overstrain, can cause problems covering the area of the shoulder joint, neck and arm. But this is only part of the whole picture: as a result of muscle compensation, which runs along the kinetic chain, the negative impact of overexertion of the pectoralis minor muscle can even affect the lower back and pelvic region.

How to Relax the Pectoralis Minor: Stretching and Trigger Point Massage

The figures below show the location of the trigger points of the pectoralis minor muscle and the scheme of reflected pain when pressing these points:

Fortunately, the pectoralis minor responds well to massage therapy and/or stretching. However, it is worth noting that it is not so easy to cope with an overstrained pectoralis minor muscle on your own, therefore the site recommends either contacting a specialist (which, of course, is better), or asking a friend/spouse/relative for help.

Stretching to eliminate trigger points of the pectoralis minor muscle:

Pectoralis minor trigger point massage:

To perform a massage of the pectoralis minor muscle, it is better to contact a specialist who can correctly determine the location of the trigger points and effectively influence them. At home, massage can be performed with a tennis ball in a prone position (placing the ball on the floor) or standing (holding the ball between the wall and the pectoralis minor muscle):

In addition to stretching and massages, try exercises to strengthen the antagonist muscles of the pectoralis minor.

Focus on the middle and lower part of the trapezius muscle, diamond-shaped, pay attention to the serratus anterior, infraspinatus, and dorsal deltas.

Do you want to build big, strong and sculpted chest muscles that will finally allow you to wear tight t-shirts? Scientific knowledge will help you with this!

Many guys go to the gym to build massive and sculpted chest muscles. Very often you can see how a novice athlete performs 20, 30, or even 40 sets of bench press in one workout. That many sets can take a toll on your shoulders, and there are plenty of other great chest exercises out there.

I want to tell you how to train your chest more effectively, how to work specific muscles, and how to get the most out of your trips to the gym.

To effectively work out the muscles of the chest, you must understand how they are arranged. Here's what you need to know about chest muscles.

Large pectoral muscles

These are the muscles you need to work on the most. They are the largest of all the muscles of the chest, and consist of 3 parts: the clavicle, the sternocostal part and the abdominal part. This is very important to know, because each of them can be worked out through certain exercises.

Clavicular part

It is located in the upper part of the pectoralis major muscles. It starts from the collarbone, runs down to the upper chest and is attached to the humerus. Most guys want to pump up this particular part of the chest, so we will pay special attention to it.

Sternocostal part

It is slightly larger than the clavicle. It originates from the sternum, crosses the chest and is attached to the humerus.

Abdominal

It originates at the sheath of the rectus abdominis muscle (most of the connective tissue that surrounds the abdominal muscles), crosses the rib cage and attaches to the humerus.

Small pectoral muscles

They are located under the large pectoral muscles. They are very small, so you don't have to spend too much time developing them.

The pectoralis minor muscles originate from the shoulder blades and attach to the 3rd, 4th and 5th ribs. These muscles should not be given too much time to train. I just want you to be aware of their existence. Basically, these muscles help us breathe.

Serratus anterior muscles

They begin in front of the ribs, pass under the shoulder blades and are attached along their edges. In bodybuilders with a good definition, they are very visible.

Although these muscles do not require much time to work there either, they are important for building balanced muscles and strengthening the shoulders.

Bone Anatomy

Bones and joints play an important role in the functioning of the chest and affect the effectiveness of chest muscle training. You will not be able to pump up your chest if you do not follow the movement of the shoulder blades, shoulders and elbows.

shoulder blades

The movement of the shoulder blades is an important part of the pressing exercises. When doing the bench press, you should bring them together to generate more force. Although the shoulder blades are located at the back of the body, they play an important role in training the chest muscles.

Shoulder joints

These are the joints between the humerus and the shoulder blade. They play an important role in chest training. Shoulder joints are also more prone to injury than others. If you incorrectly take the starting position in a particular exercise, you can seriously damage them.

Elbows

Many people forget that when doing any of the press exercises, they extend their arms at the elbows. Elbows should move smoothly and not create pain so that you can train your chest muscles as efficiently as possible.