You might think of the pushup as an exercise designed to build strength in your arms and shoulders, but it's more than that. Pushups provide a full-body workout without the need of expensive weight-training equipment. By keeping your body in a straight alignment as you lift up and down with your arms, you challenge the core muscles of your abdomen, back and thighs. The military commonly forces people in basic training to do pushups on a daily basis, but this might not be advisable for you, depending on your intensity and overall fitness level.
Effects of Strength Training
When you exercise your muscles, you tear tiny fibers that need to heal before you work them out again. This process of regeneration is what bulks muscles up. If you're doing enough pushups to make your muscles sore afterward, you must give those muscles at least a day to heal, so doing pushups every morning is a bad idea and could lead to serious injury.
Building a Tolerance
Perform pushups every other day for an extended period and your muscles will likely build a tolerance for the exercise, meaning you're maintaining a certain degree of strength and tone but not tearing many fibers up to build muscle mass. When you reach this point, it's probably safe to do pushups every morning.
The Pushup Push Workout
Former Navy SEAL and fitness expert Stew Smith devised a pushup routine that involves daily pushups for an extended period followed by a few days of rest. His "Pushup Push Workout" involves 10 consecutive days of doing 200 pushups. On odd days, you do them in "as few sets as possible" and on even days you spread out sets of pushups throughout the day to reach 200. When you've done this for 10 days, avoid any exercise to your triceps, chest and shoulders for three days. Mr. Smith does not recommend you perform this regimen more than once every six months.
Pushups will focus on different muscles if you vary the position of your hands on the floor. Place your hands in a wide stance, extending them farther out from your shoulders, to target your chest muscles. Placing your hands closer together, so that they are directly under your shoulders, shifts the intensity to your triceps and shoulders.