Any kind of impact on the physical body becomes many times more productive if a person understands what muscles he uses, how they depend on each other and how to work them out as much as possible to get a quick and high result. In this article, we will look at simple and understandable examples of the extensor and flexor muscles, their work and interaction features.
What are the opposite muscles called?
The human musculature is designed in such a way that many muscles have "brothers" that do the exact opposite work: at the moment when one muscle tenses, the opposing muscle relaxes, and vice versa.
These muscles - flexors and extensors that control the movement of the human body or individual limbs in space, are called antagonists. This is how a person makes movements - thanks to the control system strictly coordinated by the brain and the coordinated work of the muscles that move the skeleton.
How do they work?
The brain sends an impulse to the nerve endings of a muscle, such as the biceps of the arm, and it, contracting, bends the arm. Triceps - extensor of the arm - in thisthe moment is relaxed, as the brain gave the appropriate signal to him.
The flexor and extensor muscles, that is, antagonists, always work in harmony, mutually replacing each other, but sometimes they can work simultaneously, maintaining a motionless, that is, a static position of the body in space. A vivid example of such work is the well-known plank pose, in which the body hangs motionless above the floor, resting only on the hands and toes. Most of the main flexors and extensors of the muscles in this position do exactly half of the work necessary for them, as a result, the body maintains this position. If a person does not strain, say, the abdominal muscle, then his back becomes difficult, because under the pressure of gravity, the lower back begins to sag and sag. Hands down along the body are completely relaxed antagonist muscles, and an outstretched arm in front of you at shoulder level is a synchronous work of both muscle groups.
What determines the quality of movement?
Quality work of the flexor and extensor muscles depends on several factors:
- The amplitude of movement mainly depends on the length of the muscle fibers and their restraining factors, for example, muscle spasm or a post-traumatic scar greatly reduce the range of motion, and elasticity and good blood flow, on the contrary, significantly add amplitude to the work of the muscle. That is why it is important to warm up the body well with dynamic movements before training in order to saturate the muscles with blood.
- The strength of a muscle depends on two aspects: the magnitudethe lever that the muscle uses, and directly the number and thickness of the muscle fibers that make it up. For example, lifting a 10 kg kettlebell using the entire length of the arm is easy (big lever), but lifting it with just a hand will be more difficult. It is the same with the number of muscle fibers: a muscle that is 5 cm across is several times stronger than one that is only 2 cm thick.
- All muscle movements are controlled by the somatic nervous system, therefore, all body movements depend on the speed and quality of its work, especially the coordinated actions of the flexor and extensor muscles.
If an athlete knows about the correct work of the muscles, his training becomes more conscious, and therefore correct, the level of efficiency increases significantly with less energy.
Examples of Antagonist Muscles
The simplest examples of flexor and extensor muscles:
- Biceps femoris and quadriceps are the muscles of the flexors and extensors of the leg, or rather the hips. The biceps is located behind, attached to the ischium at the top and bottom, passing into the tendon, adjacent to the femur in the area of the knee joint. And the quadriceps, an extensor, is located on the front side of the thigh, is attached by a tendon to the knee joint, and is attached to the pelvic bone with its upper part.
- Biceps and triceps are the flexors and extensors of the arm, located between the elbow and shoulder joints and attached to them by powerful tendons. They are the main muscles that form the shoulder, control the vast majority of arm movements onflexion and extension.
You can often notice that if there is a too active extensor, then, as a result, the flexor muscle will be in a passive state, that is, not sufficiently developed, which creates inadequate body movements with a greater loss of energy than in harmoniously trained people (yogis are an example).
Another example of antagonist muscles
The rectus abdominis and longitudinal along the spine, along with the psoas muscle, are also prominent representatives of the flexors and extensors of the body, and they are the most global, because thanks to their coordinated and uninterrupted work, the human body takes various positions in space: from the vertical position of the torso to bending into an arc or, conversely, back bending.
And if a person is working to correct his posture: eliminate kyphosis, correct scoliotic curvature or remove hyperlordosis in the lower back, he needs not only to work out the extensors of the spine and lumbar muscles, but also to actively pump the muscles of the press, in particular the longitudinal muscle belly.
Pectoral muscles and rhomboid backs
These two couples are also antagonists, although they are often undeservedly classified in other categories. The relationship between spasm of the pectoral muscles and passive rhomboid muscles of the back has repeatedly become an area of study for physio- and yoga therapists, kinesiologists and rehabilitators. The large and small pectoral muscles are shaped like a fan. They are located on the front of the chest,originate in one bundle at the collarbones, the lower - at the upper abdominal wall and are attached to the crests of the humerus. Spasm of the pectoral muscles can be determined not only by the stoop of a person, but also by the position of his hands, lowered along the body. His arms from the shoulder and down to the wrist will be screwed in, that is, the hands will look back with their palms.
The rhomboid muscles are located between the shoulder blades, controlling their work together with the trapezoid, which, in turn, directly depend on the freedom of the shoulder muscles, in the area of \u200b\u200bwhich there is already an attachment of the pectoral muscles. As a result, a person works on stoop, loading the back muscles, but in fact he needs to first get rid of the hypertonicity of the pectoral muscles, then work out the extensor and flexor muscles of the neck, which will give freedom to his posture.
