Overhead Tricep Extension On Ball

Lying on ball with head and shoulders resting on ball. Activate your core making sure you keep the center of your body in a bridge position and core muscles tight. Raise dumbbells above chest keeping them over shoulders. Bend at the elbow allowing only your forearm to to move towards your head until you reach 90 degree angle. Draw dumbbells to starting straight arm position and repeat.

Make sure you are only moving arm at the elbow joint, not the shoulder. This is a single joint movement.