The bench press is one of the most popular strength training exercises around. Using barbells or dumbbells, bodybuilders perform bench presses to build upper body muscle size, powerlifters to test upper body strength and athletes to gain functional strength for sports. Knowing what muscles are involved in the bench press can help you decide whether the bench press is for you.
The Power Behind the Press
The main muscle used in any exercise is properly called the agonist or, sometimes, the prime mover. This muscle is also the target muscle of the exercise and the reason for doing a particular movement. In the bench press, the agonist is the pectoralis major, pecs for short, and your chest muscles. The bench press is known for being an effective chest-developing exercise and uses the central part of the pecs -- the sternal region.
Synergists Lend a Helping Hand
The bench press is a compound exercise, which means movement occurs at more than one joint at the same time, so along with the pecs, other muscles are involved. These muscles are called synergists and can be thought of as helpers or secondary muscles. The synergists in the bench press are the deltoids or shoulder muscles; the triceps, which extend your elbows; the serratus anterior, which fixes your shoulder blades to your ribs; and the clavicular or upper part of the pecs.
Braced for Action
To prevent unwanted movement and to ensure you have a stable base from which to press the weight up, muscles called stabilizers work to hold your body in the correct position. Deep shoulder muscles called the rotator cuff hold your shoulder joint in place, and your latissimus dorsi does likewise. A strong lower back arch helps you to generate maximal pec power, so your erector spinae or lower back muscles also get in on the act, as do your abs. Top powerlifters also drive their feet into the floor to ensure they are as rock steady as possible, and this means the glutes and hamstrings also can be considered fixators.
The Pressing Matter of Safety
It's all too easy to get into serious trouble when doing the bench press. You load up the bar, start lifting the weight and then realize you have started a rep you just can't finish. Gravity exerts its power and, despite your best efforts to push it back up, the bar starts to descend toward your chest. A heavy bar can crush your chest or neck, so to avoid such dangers, always bench press with a spotter on hand to help you if you get into difficulties. Alternatively, bench press in a power rack.