This is a great exercise to improve core strength and stability.
- Begin on your stomach on the exercise ball, hands on the floor in front of you. Roll over the ball until just your shins are resting on the ball and you are in a push-up position. Remember to keep your arms slightly bent.
- Engage your abs. Slowly flex your hips, pulling your knees in towards your chest. Hold this position for a second or two and then slowly return to the starting position.
- Start with 7-10 repetitions of this exercise and work your way up to keep it challenging.