Push-ups are the quintessential calisthenics exercise, but you may wonder exactly what you're working when someone tells you to drop and do 50. The muscles of the chest, shoulders and triceps engage most, but the push-up also provides conditioning for your abs, back stabilizers and thighs.
Primary Muscles Worked
When you do push-ups, you feel your arms and chest working. The primary muscles worked are:
Pectoralis Major: The pectoralis major is a large fan shaped muscle that makes up your chest wall. It has a sternal, or lower, portion that is most activated during the push-up. The clavicular, or upper region, that's near the collar bones, also works during a push-up, but to a lesser extent. Strong pecs assist you in throwing and pushing actions.
Triceps Brachii: The triceps are a muscle with three heads, or insertion points, located at the back of the upper arm. The primary function of the triceps is to extend the elbow joint.
Anterior Deltoids: The anterior deltoids are located at the front of the shoulder. During a push-up they support the action of the pectoralis major. Anterior, or front, deltoids also help you raise your arms up in front of you.
Biceps: This two-headed muscle provides support for your arm as your triceps activate. The shorter head is what works during the push-up.
Rectus Abdominus: This is a broad and long muscle that covers the front of your torso and, when toned, is responsible for that six-pack look. During a push-up, the rectus abdominus engages as you hug it in to keep your body straight.
Obliques: These abdominal muscles are at the sides of your waist and are responsible for side bending and rotation. They activate during the push-up to prevent twisting and other unwanted torso movement.
Quadriceps: During a full push-up, the quadriceps also engage to keep your body straight. They support your lifted legs and toes rooted in the floor.
Erector Spinae: This is a set of muscles along your spine. They engage in conjunction with your rectus abdominus and obliques to keep your back rigid.
The push-up is a compound exercise, as it activates multiple joints. Your body is required to work in symmetry, making it one of the most functional exercises you can do.
Remember, when you do a push-up to keep your form in check. Your hands are in the floor about shoulder distance apart with the hands flat, rather than domed. Bend your elbows at a 45-degree angle with your torso, rather than allowing them to flare out to the side.
Most importantly, keep your trunk stable and straight as you push up and down. This means no hiking of the hips or sagging into the lower back. This cheats your core from working and puts your shoulders and elbows at risk of injury. If you find it too hard to lower your chest to the floor without sagging, simple brace your knees in the mat to build the initial strength.
The way you do the push-up affects how much activation each of the primary muscles get. Try these to add dimension to your upper body and introduce additional challenges:
Inclined Push-Ups: Usually slightly easier than a standard push-up, especially if you choose a high incline. You'll work the sternal portion of the pectoralis muscle most with this move.
Declined Push-Ups: Place your feet on a box or weight bench to put greater emphasis on the anterior deltoids and upper, or clavicular, pectoralis major.
Diamond Push-Ups: When you keep your hands close together under your chest and hug your elbows in against your torso as you press up and down, your triceps brachii get more activation.
Unstable Push-Ups: Push-ups done against a stability ball or other unstable surface makes your core work harder to stabilize you.