Lie on your back with your legs on a stability ball.
The closer the ball is towards your feet, the harder the exercise.
Tuck in your navel and lift your hips straight up, driving the movement from your buttock muscles.
Once you reach a straight line from your shoulders to your feet, try to lift one extended leg in a slow and controlled movement.
Make sure your pelvis stays level.
Alternate your legs for the required time.
