The push-up is an excellent exercise because it engages the entire core region and the upper body region. Start with modified push-ups (which keep the knees on the ground) for 5 repetitions, then progress to 10 repetitions. Once you are comfortable with 10 repetitions, progress to standard push-ups.
Step By Step Instructions
Lie in a prone position (flat with the chest down) on the mat, place hands under your shoulders, and push your body up so your arms are in a straightened positioned. Focus on keeping your back and hips level and the core engaged.
Lower the body down so the arms are at a 90-degree angle at the elbows. Push back up to the starting position. Repeat until repetitions are complete.