Agonist

The agonist refers to the muscle that is primarily responsible for a specific movement during exercise or in anatomy – the muscle that does the main work during that movement. For example, during a bicep curl , the biceps are the agonist, as they are responsible for bending the elbow. Agonists often work in functional muscle chains and are supported by synergists (supporting muscles) during complex movements.

The antagonistI'm is the counterpart to the agonist. It performs the opposite action of the agonist, helping to control movement and maintain balance in the joint.