Which muscle is the primary mover during elbow flexion?

The primary mover during elbow flexion is indeed the biceps brachii. This muscle performs the primary role in bending the elbow by shortening and contracting, which pulls the forearm closer to the upper arm. The biceps brachii has two heads that originate at the shoulder and insert on the radius in the forearm, allowing for effective flexion of the elbow joint.

In addition to its role in elbow flexion, the biceps brachii also assists in supination of the forearm. This dual functionality makes it particularly important not only for lifting but also for tasks that require turning the palm up or forward. While the brachialis is also involved in elbow flexion, especially in certain positions, it is the biceps brachii that is most prominently active, particularly when the forearm is in a supinated position.

Understanding the involvement of these muscles helps to grasp the mechanics of elbow movements and their applications in various physical activities.