What defines antagonistic muscles?

Antagonistic muscles are defined by their function in pairs where one muscle contracts while the other relaxes. This arrangement allows for precise movement and control. For example, when you bend your arm at the elbow, the biceps muscle contracts to lift the forearm while the triceps muscle relaxes. This coordinated action is essential for producing smooth and effective movements in the body.

Since antagonistic muscles operate in pairs to create opposing actions, they complement each other in their roles, working together to facilitate a range of motions, from simple movements to complex physical activities.