In an antagonist muscle pair, what does the antagonist muscle do?

In an antagonist muscle pair, the antagonist muscle specifically acts to return the bone to its original position after the agonist muscle (the primary mover) has contracted to produce a movement. When one muscle contracts, the antagonist muscle relaxes to let that movement occur; then, when the agonist relaxes, the antagonist acts to allow the bone or joint to return to its starting position or to control the return movement carefully. This function is crucial for coordinated movement and helps prevent injuries.

The role of the antagonist is especially important in controlling the speed and extent of the movement, ensuring that it is smooth and does not become erratic. Understanding the relationship between agonist and antagonist muscles helps in studying muscle coordination and overall functional anatomy.