Hold a stability ball against the wall.
With the ball in the small of your back, lean against the wall, with your feet away from the wall and shoulder width apart.
Tie a tensioned resistance band around your thighs, just above your knees.
Your back and buttocks should remain in contact with the ball throughout.
Slide down the wall, aiming to reach horizontal with your thighs.
Your knees should be at 90 degrees at this point.
Push yourself back up the wall, driving the movement with your buttock muscles.
