Which muscle group is responsible for moving the joint during a movement?

The muscle group that is responsible for moving the joint during a movement is known as the agonist. Agonists are the primary muscles that contract to produce a specific movement, effectively acting as the main muscle force in the action. For example, during a bicep curl, the biceps brachii acts as the agonist to flex the elbow joint.

In contrast, the antagonist muscle group serves to oppose the movement created by the agonist, helping maintain balance and control. Stabilizers are muscles that maintain posture or stabilization of the joints throughout a movement, ensuring the body remains in a steady state. Synergists assist the agonist by helping to facilitate the movement, often by reducing unwanted movements or providing additional force. However, it is the agonist that is primarily responsible for generating the movement at the joint, making it the correct answer in this context.