Fitour Primary Personal Training Certification Practice Test 2026 – Your All-in-One Guide to Certification Success!

The prime mover, also known as the agonist, is the muscle that is primarily responsible for initiating and carrying out a specific movement at a joint. When a muscle contracts and causes a particular action, it is classified as the prime mover for that movement. For example, during a bicep curl, the bicep brachii acts as the prime mover as it contracts to flex the elbow. This role of directly causing the movement distinguishes the prime mover from other muscles involved in the action, such as stabilizers or antagonists, which have different functions in the kinetic chain during movement. The prime mover is crucial in ensuring that the desired motion occurs efficiently and effectively.