Why would you do a knee push up?
The knee push up is the progressive stage from the box push up to the strait body push up. The idea of the knee push up is the same as the strait body push up yet taking some of the weight off the exercise due to a shorter leverage. This takes some of the weight off the arms and chest but also takes a lot of the pressure off the stomach and back. This exercise is great for people with less core strength and back problems. Remember this is only a exercise to help those areas and poor core strength needs to be delt with and move this exercise into the next phase.