Size does matter

Is it crunch time again? If so, you'd do well to get off the floor and instead bang out some sets of this ab exercise on a Swiss ball (or stability ball, physio ball, exercise ball, or whatever you want to call it). But, should you just go and use any sized Swiss ball? Not if you have a choice.

According to Men's Health magazine, the perfect ball should allow your entire torso to be supported and in full contact with the ball at the bottom of the move. A larger ball has a gradual arch, so you won't feel as much of a stretch in your abs. A smaller ball, by contrast, has a more abrupt arch, placing your body in a more pronounced stretch position.

So, aside from how you fit on a Swiss ball, you should also take your fitness level into account. As your core strength and flexibility improves, drop down to a smaller size for best results.