How fit are you? Guess who works out five times a week, who works out three, and who doesn't go near the gym. Then turn the page to find out how you can get your best body ever.(The Body Issue)

weekly workouts: 3

"After six weeks of Pilates, I lost weight, toned my abs, and lifted my butt."

Mary, 32 (5'3", 118 lbs.)

Her workout: Pilates three times a week; one hour per session.

Why her body looks this way: Mary is a mesomorph--she's naturally lean and builds muscle easily. That might be why she saw such dramatic results from her Pilates workouts in such a short time.

Mary's strong stomach shows off the toned torso and midsection that Pilates is famous for. The workout is also known for creating a long, lean look--as opposed to a cut, weight lifter's body--thanks to the fact that you use fewer muscle fibers with Pilates than you do with weights.

Pilates builds endurance--but not bulk or power--through isometric movements (like holding a sit-up position) and with movements in which you work against gravity (as you do with arm circles). Increased endurance is an advantage in your midsection, where you don't really need to use explosive power in an average day, says Joshua Dobbs, M.S., an instructor in exercise physiology at Ball State University in Muncie, IN.

What will Pilates do for you? A one-hour Pilates class of video three times a week will help tone and trim your midsection. It should also improve your posture (so you'll look more poised, self-confident, and even thinner) and reduce your risk of back pain.

Is it a better core workout than crunches? That depends on what you're going for. Pilates incorporates twisting and bending moves that he]p you with everyday activities (like, say, hefting a suitcase). And it focuses on the front, back, and sides of the torso--something many people forget to do in their core workouts. But Pilates alone won't…