Lie face down with ball under your hips. Bend your left knee and lift up towards your chest. Finish by extending and driving your left leg behind you. Return to the starting position and repeat.
Lie face up on floor, legs straight in front and neck resting on pad. Place elbows on pads and grip bar or place hands on bar above head. Slowly lift your legs towards your chest while keeping your knees relaxed and with a slight bend. Then proceed to lower your legs back down to the floor. While doing this exercise, concentrate on lifting your legs with your abs and not your back or legs. Do not allow muscle to relax before next repetition.