Get your abs & butt on the ball

Tight abs and a sculpted butt are tops on everyone's summer wish list, but doing the usual crunches and squats over and over can get tedious and even slow down your progress, if they're the only moves you've got in your repertoire. The good news: You might get better, and faster, results by using a stability ball.

When you do crunches and squats, if you don't pay close attention to form, it's easy to cheat and avoid using the muscles you most need to strengthen, says San Francisco trainer and Pilates expert Elisabeth Crawford, author of Balance on the Ball (Equilibrio, 2000). So Crawford designed this exclusive Pilates-based abs and butt workout that makes cheating almost impossible. Using a stability ball, these challenging yet graceful moves force you to engage more muscles and maintain total focus; if you get sloppy for just a sec, you lose your balance. The result of this boredom-busting workout is fab abs and a firmer butt with minimal sets and reps. "You get the benefits of a fitness routine and the fun of playing with a toy," Crawford says. So go have a ball!