Lie on your back with your legs bent and one foot on a football.
Cross your arms over your chest with your knees no more than hip-width apart.
Tighten your core and buttock muscles and lift up into a bridge.
Do not allow the ball to roll as you lift the leg on the floor straight out in front of you, keeping your hips up and level.
Lower the leg back down and repeat.
Monitor your hip and trunk position throughout the movement.