Hold a stability ball against a wall, placed in the small of your back.
Lean firmly back against the ball.
Walk your feet forwards, keeping your toes pointing ahead and your legs at hips-width apart.
Squat down, dropping your hips towards the floor and bending your knees until they reach 90 degrees.
Stand up straight, driving the movement with your buttock muscles.
Make sure your body remains straight and knees travel directly forwards over your toes throughout this exercise.
