Q: I want to make my ab workouts more intense with a stability ball, but I don’t know where to start. Any suggestions?

A: First thing’s first: make sure that the ball is the correct size for you. Determine this by sitting on a stability ball with your feet shoulder width apart. If your knees are at a 90 degree angle, the ball is the right size for you and you are ready to start.

To perform an abdominal crunch effectively, start by moving your hips forward and lying back onto the ball. Then place your hands across your chest. Once you are in this position, concentrate on raising your chest and shoulders up to a 45-degree angle. Now squeeze your abdominals and return to the starting position. Perform three sets of 15 to 20 repetitions three to five times each week.

To increase the difficulty, place your feet closer together and your hands at the sides of your head.

Shaun Karp is a certified personal trainer in Vancouver. For further information call his office at 604-420-7800.