What muscles belong to the muscles of the trunk? Muscles of the human body

For the implementation of all kinds of movements in the human body, there are muscles that are divided into three main types. These are: skeletal, cardiac and smooth. Each has its own purpose and a different structure.

The purpose of the muscles in the human body

The very first and main purpose of them in the body is to support bones and internal organs. The muscles completely cover the human body and carry the main goal - the support and provision of motor functions. Each movement of our body provides muscle tissue, and this is not only the movement of the arms and legs, but blinking, swallowing, processing and movement of food, the work of the heart. Without muscle tissue, the human body is unable to function.

The structure of the muscle corset

All human muscles can be divided into groups according to their purpose and location.

It is much easier to consider them in larger groups, for example, dividing them into three main ones. So, the muscles of the body include:

• dorsal;
• thoracic;
• abdominal.

The muscles of the trunk include the dorsal superficial and deep.

Superficial back muscles

The superficial muscles are represented as follows:

• The trapezius muscle, which is attached to all the vertebrae of the thoracic region and its second end to the clavicle and scapular spine, is responsible for bending the head. She is responsible for the movement of the scapula. The upper part raises, and the lower part lowers. When the arms are pulled back, the middle part of the muscle brings the shoulder blades closer to the spine. Also attached to the base of the skull and neck.
• The latissimus dorsi following the trapezius is attached to all other parts of the spine of the lower part and to the vertebrae of the anterior chest, thus covering the entire body with a full revolution. It is not only a corset for the human body, but also pulls the shoulders and arms back, while simultaneously turning them inward. She is one of those who belong to the group of "large muscles", as it is one of the largest in the whole body.
• The rhomboid muscles, both large and small, lie beneath the trapezius and attach with their bundles to the lower cervical and capture 4 vertebrae of the thoracic region, and at the other end they are attached to the bone of the scapula and are responsible for its approximation to the center.

• The muscle that lifts the shoulder blade is slightly higher, above the rhomboid on the back of the neck. One end is attached to two cervical and two thoracic vertebrae, and the second part is fixed on the upper rib. This is a good holder for the neck, while raising the shoulder blade up.
• Lower and upper posterior dentate muscles. The lower one is located obliquely on the back and begins in the lumbar region, attaching to the first four lower ribs. Responsible for lowering the ribs. The upper one is located under the diamond-shaped and attached to the upper ribs, starting from the 2nd to the 5th, with its other end clinging to the cervical vertebrae. Responsible for raising the ribs.

Deep back muscles

The lateral and medial muscles, which are located on both sides of the spinal column, extend from the sacrum to the back of the head, also belong to the trunk muscles. Lateral are responsible for straightening the back and are superficial. The medial muscles are located at the very bottom relative to the others and consist of groups of small muscle bundles thrown through the spine. And also such muscles include the belt muscles of the head and neck, which participate in all movements and are a kind of corset.

Pectoral muscles

The muscles of the chest can be divided into two groups, which include the upper muscles of the limbs and shoulder girdle:

• The pectoralis major muscle is the uppermost one, having a triangular shape and starting from the clavicle bone near the shoulder, joining the sternum from the 2nd to the 7th rib. The pectoralis major muscle is responsible for the movement of the arm forward and inward, and is also involved in lifting the ribs on inspiration.
• The pectoralis minor muscle is located somewhat deeper and is attached at one end to the scapula and the other to the ribs, from the 2nd to the 5th. Participates in its movement forward and downward, and, like a large one, is an inspirational rib lifter.
• Another representative of the small muscles is the subclavian. She is stretched between the collarbone and the upper right rib. Pulls it down, thus locking and holding.
• The anterior dentate muscle grasps the lateral surface of the chest. One end is attached to the 9th rib, and the second - to the lower corner of the edge of the scapula. Pulls it forward, rotates. This is necessary for the movement of the hand above a horizontal position. Also, in collaboration with the rhomboid muscle, presses the shoulder blade tightly to the body.

Breathing muscles

The muscles of the body also include those involved in breathing. The external and internal intercostal muscles are located between the ribs and are the main participants during inhalation and exhalation.

The diaphragm is the most unusually located flat muscle, which has a domed appearance. It is directed convex part up. By its action, it is a piston pump for the implementation of the breathing function. It is this muscle that compresses and decompresses the lungs, causing them to fill with air and freeing it from it. The diaphragm is attached around the entire perimeter of the chest. It is stretched over the ribs, spine, lower chest.

Abdominal muscles

They are represented by five main ones, including the abdominal muscles.

• The external oblique muscle is attached to the lower eight ribs, and back to the iliac crest, thus, located under the pectoralis major and to the level where the limb muscles begin to attach, such as the femur, quadriceps and others.
• The internal oblique muscle is located under the external, starting from the lower rib, attaching to the lumbo-thoracic fascia and inguinal ligaments, and back to the lower ribs. The oblique muscles serve as a corset for the internal organs of the abdominal cavity and are involved in flexion, extension and tilting, as well as turning the body.
• The transverse muscle is located below the oblique and attached to the lower ribs, starting from the 6th, and then to the lumbo-thoracic fascia, iliac crest and to the inguinal ligament.
• The rectus abdominis muscle lies outside and consists of 8 muscle bundles that pass into each other. They begin on the sternum and descend from 5 ribs to the pubic bone itself. Their second name is the muscles of the press. The rectus is the main muscle in flexion and extension of the body in the forward direction.
• The square muscle of the lower back begins from the iliac crest and is attached to the lumbar spine, forming the posterior abdominal wall. Holds the abdominal muscle corset. Participates in the extension of the trunk back, as well as in the forward bending.

Muscle movement fills the body with life. Whatever a person does, all his movements, even those that we sometimes do not pay attention to, are enclosed in the activity of muscle tissue. This is the active part of the musculoskeletal system, ensuring the functioning of its individual organs.