ACSM Personal Trainer Certification Practice Exam

Elbow flexion during exercise predominantly activates which muscle?

1. Biceps

2. Triceps

3. Deltoids

4. Quadriceps

The correct answer is: Biceps

Elbow flexion primarily involves the biceps brachii, which is the main muscle responsible for this action. When performing exercises that require bending the elbow, such as bicep curls or pull-ups, the biceps contract to bring the forearm closer to the shoulder, effectively flexing the elbow joint. This muscle is particularly well-equipped for generating force during flexion, making it crucial for movements that involve lifting or pulling the arms. The other muscles mentioned do not play a primary role in elbow flexion. The triceps, for example, are the antagonistic muscle that is responsible for elbow extension, working in opposition to the biceps. The deltoids are associated with shoulder movements rather than elbow flexion, and the quadriceps are primarily involved in knee extension and are not related to the movements of the elbow joint. Understanding the specific roles of these muscles helps in designing targeted exercise programs and ensuring proper technique during strength training.