Lie on your back, with your legs bent and feet on a step.
Ensure your legs are hips width apart.
Tighten your buttock and abdominal muscles, and press your heels into the step.
Lift your hips up, so that your weight is on your shoulders.
There should be a straight line from your shoulders to your knees.
Control the movement back to the start position.
Notice how your hips stay level throughout this movement.
