Lay on the floor in a supine position. Place the stability ball under your legs somewhere between your calf and heel. Your arms should remain at your side on the floor slightly under your body to help control your position. Push your legs down into the ball as you push your hips upward until your body has created a straight line. Hold at the top and slowly lower your body back to the floor. Squeeze your hamstrings and glutes at the top of the movement to increase intensity. The further the stability ball is from the hips the more difficult the exercise.
Stability Ball Hip Extensions