BEGINNER OPTION (Left) - Starting position is in a tall plank or push-up position. Begin exercise by slowly lift in one hand and tapping the front shoulder of your opposite arm. Make sure to keep your back straight and abdominals tight as you alternate the movement from one hand to the other. Repeat as indicated. ADVANCED OPTION (Right) - Starting position is in a handstand against the wall, maintaining a hollow body position and only your toes touching the wall. Lift your hand and touch your shoulder with the opposite arm. Maintain a hollow body position and lift with your arm on the floor. Repeat as indicated.