What is the role of synergist muscles during joint movement?

Synergist muscles play a crucial role during joint movement by stabilizing and supporting the primary movers, or agonists, as they contract to produce movement. While the agonists are responsible for the primary action, synergists assist by providing necessary stabilization to joints, which helps maintain control and alignment during various movements. This stabilization is essential as it prevents unwanted motions that could lead to injury or diminish the effectiveness of the movement.

For instance, when performing a bicep curl, the biceps brachii are the primary movers, while other muscles such as the brachialis serve as synergists to help keep the elbow joint steady. This support ensures that the movement is smooth and controlled, allowing the agonist to do its work efficiently.

Thus, the role of synergists is fundamentally about steadiness during movement, ensuring that the joint remains stable and functional as the primary muscle takes action.