Although I do crunches religiously, my abdominals aren't nearly as toned as I would like. I just can't seem to fatigue them, no matter how many reps I do. How can I add extra resistance to my abdominal workouts?

A: "It's quality, not quantity, that counts in any form of exercise, so 200 sloppy crunches will produce nothing compared to 20 core-conscious moves," says Scott Cole, co-author of Athletic Abs (Human Kinetics, 2003; $19) and creator of the Best Abs on Earth video (Natural Journeys, 2003; $20; both available at

If you're not feeling resistance when you perform crunches, it's probably because you're making mistakes in technique, Cole says. For instance, you may be crunching too quickly instead of taking two full seconds to rise and two to lower, or you may be lifting from your shoulders and neck rather than from your torso. However, even a crunch performed correctly isn't the best exercise for your abs. Cole recommends more-challenging exercises that require your abdominals to function as stabilizers for your entire body and to work in conjunction with other muscle groups. For example, do your crunches on a stability ball. "Drape yourself backward over the ball, and begin your crunch with your head slightly below your hips," Cole says. This position uses gravity to provide more resistance. Plus, your abs (and other muscles) will have to work harder to keep your body from rolling off the ball.

In his book and video, Cole demonstrates dozens of challenging abdominal exercises using a variety of equipment. Our own SHAPE ... Your Abs DVD ($20; available at offers four five-minute ab routines incorporating a variety of our best toning moves.