I want to introduce you to a lesser known push-up. It primarily isolates your triceps, and it is a little bit tougher than the Close Grip Triceps Push-Up. This exercise also trains your muscles to get ready for the tougher one arm push-up.   You get into push-up position, but you support your body with one hand on the ground and one hand on either a basketball or a medicine ball. Bring your chest down to at least the level of where your hand is on the ball, keep your…