Ball Reverse Hyperextensions
Lay with your hips on the ball. Use your hands for support as shown in the first picture. Your legs should be straight and feet should be on the floor.
Raise your legs and contract the glutes.
Hold for 1-2 seconds, then slowly return to the starting position.
Be sure that you are comfortable and stable on the ball before trying any ball exercises.
Search on FreeTrainers.com