Which muscle is primarily used during a bench press?

The pectoralis major is the primary muscle engaged during a bench press, making it the focal point of this exercise. This large muscle, located in the chest, is responsible for the movement of the humerus in different planes, especially in horizontal adduction and shoulder flexion. During the bench press, when pushing the barbell away from the chest, the pectoralis major is heavily activated, working to lift and stabilize the weight.

In addition to the pectoralis major, other muscles play supportive roles. For instance, the deltoids assist in shoulder stabilization and movement, particularly in the pressing phase. The latissimus dorsi also contributes to shoulder adduction and extension, but its primary role is not as pronounced as that of the pectoralis major during this particular movement. Similarly, the trapezius helps with shoulder girdle stability but is not the primary mover in a bench press action. The focus of the exercise squarely lies on the pectoralis major, which showcases its strength and prominence in upper body pushing movements.