If you want to look cool in the gym, but lack the upper body strength to do so, this exercise is for you. The modified ball push-up appears difficult. But in actuality, it is fairly simple to perform. The higher the ball is on your legs, the easier it is. Why is this? Well, it has to do with the distribution of bodyweight over the ball.

When the ball is positioned on your upper leg/stomach area, it reduces the amount of force required to push the weight of your upper body. Conversely, if the ball was positioned on your ankles, you would have to push about 90 percent of your bodyweight.

Instructions for the modified ball push-up are as follows:

Lie down on a workout ball. Position the ball so that it is on your upper legs/stomach area. Make adjustments as needed. Place your arms approximately shoulder width apart. Perform a push-up by bending your elbows and lowering your upper body to the floor. As your torso goes down, your feet should go up (like a see saw). Push back up to the starting position. Exhale as you push up.