Workout Devices Get Rated

Kangoo Jumps. The Bowflex. The Body Dome. The Ab Away. You've seen them on TV. You've heard the promises -- tight abs, sculpted arms, supercharged metabolism, burn calories like a furnace. But do these products really deliver?

For feedback, WebMD turned to two experts, both with the American Council on Exercise (ACE): Cedric Bryant, PhD, ACE's chief exercise physiologist, and Sal Fichera, MS, exercise physiologist and certified personal trainer with Forza Fitness in Manhattan.

Here's their advice on several "As Seen On TV" products: the Ab Away, the Body Dome, Body Flex, Bowflex, the Gazelle, inversion/gravity tables, Kangoo Jumps, spinning bikes, the Total Gym, and trampolines (mini).

The Ab Away

Bryant: "This is an abdominal 'training' product that focuses on the lowering action of a sit-up. That's fine, it's an important aspect of exercise, but there's nothing magical about it in terms of sculpting. The ads say the product is safe because of the cushioned back support. But given the dimensions of the device, it would seem that for individuals of average height or taller, it will be too short to provide any real support for the back."

Fichera: "The problem is, you are seated almost upright during the movements. I don't think that's necessarily good. In order to activate abs, you need to bend from the mid torso. If you bend at the hips like old-fashioned sit-ups, you're going to use hip flexors, not abdominals. You could do a full range of ab exercises using just your own muscles, with no machine, and get more results."

The Body Dome

Bryant: "This is a 'stability ball' but with a stable base, which allows you to do push-ups and other exercises. This kind of apparatus can be used effectively for muscle conditioning exercises. However, the infomercials hype that it can do everything -- like converting fat to muscle. That's impossible; those are two distinct tissues. Also, it claims to supercharge metabolism, which may lead people to believe they will burn calories like a furnace. That would be nice, but it won't happen."

Fichera: "It's a good product, but limited. You can't do a whole-body workout on the Body Dome. It's good for squats and crunches, but it's not at all a full-body exercise tool. It's one tool to be added to a series of others."

Body Flex

Bryant: The inventor of this program "alleges that so-called aerobic breathing is key to weight loss -- that it speeds up metabolism, allows you to burn more calories. That's really nonsensical. She says that performing 15-minute exercises is the key to stoking metabolism, which has no scientific basis."

Fichera: "Just looking at this program, it looks limited at best. I'd have to try it to see if it really did anything."