If you were to look under your arm, you would see skin, flab and muscle. The muscle found here is known in anatomical terminology as the triceps. To exercise your underarms, you need to do elbow flexion exercises that work the triceps muscles. Flexion is a movement that causes your lower arm to go from a bent to straight position.
Close-grip Bench Press
Close-grip bench presses are performed with a barbell and bench. To perform this exercise, lie face-up on the bench, grasp the bar with a slightly less than shoulder-width grip and hoist it off the supports. After holding the bar right above your chest, slowly lower it down to chest height. Once you feel a strong contraction in your triceps, push the bar back up, stop just short of locking out your arms and repeat. When you lower the bar, be sure to keep your arms in tight against your sides.
Dips are performed with two weight benches. To do the exercise, line the benches up parallel to each other and slightly wider apart than the length of your legs. After grasping the edge of one bench with your hands, place your heels on top of the other bench. Once your abs are tight, lower yourself down by bending your elbows. When your upper arms parallel the floor, pause for a second, push yourself back up and repeat.
Skull crusher is the nickname given to a lying barbell press to chin. To do this exercise, lie flat on a bench while holding a barbell straight above your chest with your hands approximately 6 inches apart. After tightening your core, lower the bar toward your forehead by bending your elbows. When the bar is within an inch or your head, push it back up and repeat. When you do this exercise, do not let your elbows flare out to the sides.
Swiss Ball Rollouts
Swiss balls are filled with air and used to work various muscle groups. To do a rollout for your underarms, place the ball against the wall at eye level, place your fists on the ball right above the apex, spread your feet shoulder-width apart and step back slightly so your body is at an angle. Once you have fully extended your arms, bend your elbows and lean forward as you roll the ball down the wall. Once your nose is close to the ball, press your fists into the ball, push yourself back to the starting position by extending your arms and repeat. When you do this exercise, keep your arms in close to your sides.
About this Author
Kevin Rail has worked in the fitness industry since 2001 and has been writing since 2004. He has professional experience as a certified personal trainer, wellness coach, motivational engineer and freelance fitness writer. He currently writes a monthly column for Ron Jones High-Performance Health. Rail has a bachelor’s degree in sports management: fitness and wellness from California University of Pennsylvania.