In the context of muscle actions, what best describes a prime mover (agonist) muscle?

• A. A muscle that assists the prime mover by adding extra force or reducing unnecessary motion during the movement
• B. The muscle that provides the primary force responsible for producing a specific movement at a joint
• C. A muscle that opposes the action of another muscle to slow or stop a movement
• D. A muscle that stabilizes the origin of the prime mover to help maintain posture during movement

Answer: (B)

Verified step by step guidance

1. Understand the role of different muscle types during movement: prime movers (agonists), antagonists, synergists, and fixators.
2. Recall that the prime mover, or agonist, is the muscle primarily responsible for generating the force needed to perform a specific movement at a joint.
3. Recognize that synergist muscles assist the prime mover by adding extra force or reducing unnecessary motion, but they are not the main force producers.
4. Identify that antagonist muscles oppose the action of the prime mover to slow or stop a movement, providing control and balance.
5. Know that fixator muscles stabilize the origin of the prime mover, helping maintain posture and allowing the prime mover to act efficiently.