Structure of the human muscles

Muscles are organs of the human body, which consist of muscle tissue, capable of contractions under the influence of nerve impulses. It is an active element of the musculoskeletal system that provides movement when moving a person in space, breathing movements, maintaining balance, voice formation, shrinking the walls of internal organs, etc. There are about 600 muscles in the human body, their share of the total mass is about 30%. Muscles are also called skeletal musculature, since they are connected to the skeleton practically over its entire surface.

Structure of the muscle

The muscle is a collection of bundles of striated fibers that are connected in first order bundles by loose connective tissue. Then the first-order beams are combined into bundles of the second and so on. All of them, united by a connecting shell, eventually form a muscular abdomen. Between the muscle tufts at the extremities of the abdomen are connective layers that are attached to the bone by means of a tendon tissue. This is the structure of the muscles. When contracting, the muscle abdomen is shortened, and its ends converge. At this time, the muscle pulls a bone acting as a lever. So are all sorts of movements.

Each muscle is a separate holistic organ, which has a definite structure, shape, and function. Each develops in a special way and has its position in the body. As suggested by the structure of man, the muscles are equipped with nerves and blood vessels. Each movement is carried out by means of several muscles.

Now let's consider the structure of muscles more specifically. Those that act in one direction together and cause a similar effect are called synergists. The same muscles that make oppositely directed movements are called antagonists. For example, the elbow joint bends the biceps (the biceps arm of the shoulder), unbends - the triceps (triceps). When flexing the elbow joint, the contraction and relaxation of flexor muscles and extensor muscles alternate, that is, they act as antagonists. But with a static load, for example, while holding the weights in a horizontal position on an elongated arm - both flexors and extensors act as synergists. From this we can conclude that the structure of the muscles excludes the performance of only one function, but on the contrary ensures their multifunctionality. Due to the fact that the muscles of both groups take part in each movement, our movements are characterized by accuracy and smoothness.

By the nature of the basic movements that they perform, and by their action on the joint, the muscles are divided into the following types:

- leading, leading,

- flexors, extensors,

- Lifting, lowering,

- rotating, etc.

There are also mimic, respiratory and chewing muscles.

They are also different in size and shape: they can be long, short and wide. The long muscles are mostly on the limbs, the short ones are between the vertebrae and the ribs, the broad muscles are on the trunk. Almost all of them are transferred through several joints, producing in them a reduction in movement.

How muscles work

With contraction, the muscle performs the role of the lever for the bone, producing mechanical work. In order for it to carry out its work, it is necessary that the energy formed during the decomposition and oxidation of organic substances that have entered the cells. Nutrients and oxygen to the muscles supply blood, it also takes away the waste product formed during dissimilation. Long-term work leads to fatigue and a decrease in their performance.

To maintain them in tone, regular muscular work is needed, which increases their blood supply. Which in turn leads to the growth of muscle mass. Strong muscles perfectly support the trunk, preventing the curvature of the spine, the appearance of stoop.