Which of the following best describes the role of antagonist muscles?

The role of antagonist muscles is best characterized by their function in allowing movement through lengthening. In any given movement, when an agonist muscle contracts to produce a specific action, the antagonist muscle must relax or lengthen to enable that motion to occur smoothly and effectively. For instance, during a bicep curl, the biceps act as the agonist when they contract to lift the weight, while the triceps serve as the antagonist, lengthening to allow the curl to happen without hindrance. This dynamic interplay between agonists and antagonists is essential for coordinated movement and proper muscle function, as it ensures that one muscle group does not overpower another, facilitating balance and control throughout the motion.