What is the function of the antagonist muscle?

The function of the antagonist muscle is to execute the opposite movement of the prime mover. In any given movement, the prime mover, or agonist, is the primary muscle responsible for the product of that action, such as flexion or extension. The antagonist works in opposition to this muscle, playing a crucial role in creating balance and control during motion. For example, when the biceps (the prime mover) contract to flex the elbow, the triceps act as the antagonist by relaxing in order to allow for smooth and coordinated movement. This balance prevents joint injuries, ensures proper movement mechanics, and allows for the dynamic stability required during physical activities.