The pectoralis major and the anterior deltoid are involved in shoulder joint horizontal flexion (adduction) in the bench press. In this action the arms travel in a plane perpendicular to the trunk. Initially the arms are out to the sides in line with the shoulders and then they move upward until they are directly above the chest.
In the shoulder girdle, the pectoralis minor and serratus anterior are involved in scapula abduction. In this action the scapulae move out to the sides of the rib cage from a position close to the spine. In the elbow joints the triceps brachii is involved in elbow joint extension. In this action the forearms move away from the upper arms until the arms are straight.