The bench press is a popular exercise for building upper body strength and size. It mainly targets the chest, shoulders, and arms, but also recruits several secondary and tertiary muscles to assist in the pushing movement. The primary muscles worked during the bench press are:

• Pectoralis major and minor (chest muscles): These are the prime movers for the bench press, responsible for doing the most work.

• Anterior (front) deltoids: These triangular muscles help the arms move forward and are responsible for lifting the weight off the chest.

• Triceps brachii: These muscles are located on the back of the upper arm and are responsible for extending the elbow joint.

Other muscles that are worked during the bench press include the biceps, serratus anterior, upper back muscles, forearms, and lats. The exact muscles worked may vary slightly depending on the specific variation of the bench press that is performed.

In summary, the bench press is an effective exercise for building upper body strength and size, primarily targeting the chest, shoulders, and arms.