To increase the speed of your upper body movements, get in a push up position and push your body up quickly and forcefully, causing your palms to leave the floor for a moment. Just make sure you keep your abdominal muscles tight so your back stays in proper form. The great thing about press ups is that they do amazing things for your upper body development. They work your arms (biceps and triceps), but they also build the muscles in your chest, shoulders, and upper back.