You will need two boxes: one at least a foot higher than the other. Place the boxes approximately 3 feet apart. Stand on top of the high box. Step off of the high box onto the floor and rebound up onto the smaller box. "Spend as little time on the floor as possible. The goal is a quick rebound and powerful explosion back up," says Lysacek. When this becomes easy, switch the boxes so that you step from the small box onto the floor and rebound onto the high box. Remember to switch your "rebound" legs after each set of six. If you want to train like Lysacek, add a weight belt or vest. Do three sets for each leg.