The push-up is the classic gym class exercise that most people do incorrectly. The push-up is still really one of the best, if not the best, upper-body strength-building exercises you can do. It hits the chest, the shoulders, the triceps, the abs, and a few other things here and there.
Push-ups by themselves aren't all that difficult for some people. But who said you need to limit yourself to only standard push-ups? After you're able to bang out 15 reps or more of the push-up, you can start the one-arm push-up, or the one-arm, one-leg push-up.
Here is how you can to do a perfect push-up:
Lie flat on your stomach, face down, with your arms by your sides.
Set up your push-up from the bottom, like this, to ensure a foolproof setup.
Lift your arms back up behind you as high as you can, but keep your elbows straight. Bend your elbows 90 degrees and plant your hands on the ground.
They should fall almost directly in line with your sternum. At this point, your arms should be tucked in closely to your sides, your elbows bent at about 90 degrees, and your forearms perpendicular to the ground.
If you’ve never done a push-up like this, it will likely feel more difficult at first, but keep your elbows in close to your body. In the long run, you’ll be stronger.
Tuck in your toes, tense your whole body, and push yourself up to the top of a push-up position.
Your chest, stomach, and hips all rise and descend at the same rate. In other words, when done right, your body should ascend and descend as a stiff and single unit — a plank of wood — and not in a wavelike or wormlike manner.
Lower yourself back down, keeping your elbows in tight, and repeat the movement.