In each movement performed during our physical exercises, the muscles perform different functions. And the main functions of the complete execution of the movement are the functions of the agonist and antagonist muscles.
In a very simple way, the difference between the agonist and antagonist muscle is that they work in opposite directions during an exercise. While one contracts, the other stretches.
In each movement performed during our physical exercises, the muscles perform different functions. And the main functions of the complete execution of the movement are the functions of the agonist and antagonist muscles. Quite simply, the difference between them is that they work in opposite directions during an exercise. While one contracts, the other stretches.
Although the definition seems simple, there are many confusion about nomenclature. Many will come to understand that the agonist muscle is one that plays a role in the production of a movement, whereas in reality the agonist muscle is only one that can produce a force that accelerates a limb around its set in a particular direction.
In addition to the agonist and antagonist, other auxiliary muscles play an important role during an exercise, ensuring that the muscles of movement agents work more efficiently. These auxiliaries are known as synergists and subdivided into fixatives and neutralizers.
Differences between muscle agonist and antagonist
Agonist and antagonist muscles work together to perform a wide variety of movements and actions. Agonist muscles react to respond to voluntary or involuntary stimuli and create the movement needed to complete a task. The antagonist, in turn, acts contrary to the agonist muscle and helps to bring the exercised member back to its original position after the end of the movement. The agonist muscle always contracts to initiate movement and the antagonist stretches and stretches allowing circulation.
However, it is only possible to define the role played by each muscle if each action is evaluated, since the same muscle can be agonist in one movement, and antagonistic in another. To move the part of the body back to its normal position, the agonist muscle, which initiated the movement, becomes the antagonist. The functions are then reversed.
The agonist muscle is also called the motor agent, by initiating the contraction necessary to move a limb. And the antagonist is reactionary. It stretches and stretches so the agonist can complete the action.
A common example of agonist and antagonist pairs are biceps and triceps, which work together to complete exercises related to arm movement. In a bicep exercise, such as the direct threading, for example, the action performed works the biceps, which in this case is the agonist muscle. On the other hand, the counteracting muscle, which causes the worked-out body part to return to the initial site, is the triceps, which in this case is the antagonist muscle.
Already in triceps exercise, the agonist and antagonist muscles invert, causing the triceps to be the agonist muscle and the biceps the antagonist muscle.
Another example is the quadriceps and hamstring muscles, which work in tune and counterclockwise to move the knee joint, as well as perform squats and leg extensions.
Auxiliary muscles: synergists
However, for the movement to be perfect and complete, there are other muscles that primarily aid the agonist's function. This is the case of synergistic muscles, which participate by stabilizing the joints so that undesirable movements do not occur during the main action. They actively participate in the movement, assisting the agonist muscle in the execution of the movement. Hence they are still known as "secondary agonists".They are not primarily responsible for the movement, but give support.
Within this group of auxiliary muscles, there are still subcategories, which classifies the fixing or stabilizing muscles and the neutralizers.
Fixers act by stabilizing surrounding structures during the movement of both types of muscles. When doing push-ups on the ground, for example, while agonists are the extensor muscles of the elbow, the abdominal muscles act as stabilizers, keeping the trunk straight, while the arms move the trunk up and down. They stabilize the origin of the agonist muscle so that it can act more efficiently.
Neutralizing muscles, such as fasteners, help prevent unwanted movement. Many muscles can produce a pulling force in more than one direction, so that an unwanted action can occur simultaneously as desired. And the role of the neutralizer is to prevent this from happening.