Push-ups are an effective way to develop powerful arm, chest and shoulder muscles. The muscle group that benefits most depends on the type of push-up. Unlike weight lifting, in which you simply add another weight to the bar, push-ups require you to change your body position. The shoulder muscles require decline positions that force you to lean forward and support your weight with shoulder strength. Several variations of push-ups can help you target your shoulder muscles.
Decline push-ups are a simple push-up variation that targets your shoulders directly. Begin in a normal push-up position, with your arms shoulder-width apart and your hands level with your ears. Place your feet on a step, chair or other elevated platform. Your center of mass is now shifted forward and the majority of your body weight is resting on your shoulders. Lower your body until your chest touches the floor, and then lift until your arms are fully extended to complete the repetition.
Hindus and Dive Bombers
Hindus and dive bombers both use the same starting position. Spread your feet slightly wider than shoulder-width apart and place your hands shoulder-width apart with your hands slightly in front of your head. Lift your butt and lower your face to the floor so your body forms an upside down V-shape. In this position, your butt should be your highest point. Make a swooping motion by moving your body down, forward past your hands, and then up so your face points toward the ceiling. End with your stomach and legs stretched out along the floor and your shoulders and head lifted up. You should feel your back muscles stretching. For a Hindu push-up, simply lift your butt and return to the starting position to complete the rep. For a dive bomber, reverse the motion. Both variations place direct resistance on your shoulders, with the dive bomber typically slightly harder to execute.
A wall stand is similar to a headstand push-up but uses the support of a vertical wall for balance and to slightly reduce the resistance. Place your hands 1 to 2 feet away from the wall -- the farther away, the easier you'll find the exercise. Kick your feet up against the wall and place your head in between and level with your hands. Lower your body until your nose touches the floor, and then push up until your arms are fully extended to complete the repetition. This exercise is very difficult and you might feel blood rushing to your head. You will get used to the feeling after a couple times and be able to do more push-ups each session, but avoid this exercise if it's overly uncomfortable.
Handstand push-ups are the pinnacle of body-weight shoulder exercises. One hundred percent of your body weight is supported by your shoulders, which act like the hips of your inverted body. By this point you should be able to comfortably hold a handstand for at least 30 seconds, although preferably a minute or more. Get into the handstand position, lower your face to touch the ground, and then raise your body until your arms are fully extended to complete one repetition. If it is too difficult to do a handstand push-up immediately, try walking on your hands to develop extra strength.