Superficial back muscles are called groups of muscle tissue that are attached to the skeleton of the shoulder girdle. They are arranged in two layers. The upper layer is the trapezius muscle and the widest, the lower - the large and small rhombus muscle.
The structure of the trapezius muscle
This broad, flat muscle occupies a position in the upper back in the posterior lower neck. It has a shape similar to a triangle. Its base is facing the spinal column, while the apex is turned towards the acromion. If you examine the trapezius muscles on both sides of the back, then they will resemble the geometric figure “trapezoid”. For this they got their name. The trapezius muscle is divided into three parts:
- upper (neck area);
- middle (upper part of the blades);
- lower (bottom of the shoulder blades and the area below them).
The muscle has short tendon bundles. They form a rhombic platform only in the region of the upper thoracic and lower cervical vertebrae. The bundles of muscle radically converge to the scapula. Here they are attached to its axis, as well as to the acromial end of the clavicle and directly to the acromion itself. In the area of attachment, between the point of attachment of the ascending bundles and the spine of the scapula, there is a small size drier bag. It is located between the bone and the tendon itself. In the place where the trapezius muscle joins the acromion, there is an acromial subcutaneous bag. She is quite large. It lies on the posterior surface of the acromion.
Trapezius muscle: functions
This muscle has many functions, but the main one, of course, is the movement of the scapula, which provides the raising, lowering and rotation of the upper limbs. Let's consider everything in detail:
- with the simultaneous contraction of all parts of the muscle, in the condition of a fixed spine, the scapula approaches it;
- while reducing the upper and lower fibers, the bone rotates along the sagittal axis;
- the scapula lift the upper muscle bundles;
- muscle during contraction on both sides contributes to the extension of the cervical spine, this allows you to tilt your head back;
- with one-sided squeezing, the front of the head turns slightly in the opposite direction.
How does a trapezius muscle swing?
So, the trapezius muscle is located in the upper back. By its size, we can say with confidence whether a person is engaged in physical training or not. If the volume of the trapezoid begins to increase, the girth of the neck also increases. It becomes more powerful and embossed. It is not too difficult to achieve that the trapezius muscle of the back becomes more massive and impressive. To do this, there is a whole range of traction exercises. This muscle is trained by lowering and raising the shoulders with weights, for example using a barbell or dumbbell. The lower part sways by the method of information-breeding under the load of the blades. But do not train this muscle group separately. This can lead to a visual narrowing of the shoulders. It needs to be downloaded in the complex.