A Workout Without The Work?

It's the workout without the work. There's an electronic device that promises to pump you up while you take it easy. It sounds mighty appealing. But before you shell out hundreds of dollars for one of these machines, find out more from Consumer Correspondent Herb Weisbaum.

It takes a lot a work to look your best, a lot of stretching and straining, a lot of pushing and pedaling and pumping up those muscles. Or at least it used to.

But if you believe the ads, there's now a better way called Electronic Muscle Stimulation, or EMS. These EMS machines are all over the Internet and in magazine ads. They promise to build up your muscles, firm up your butt, and give you rock solid abs by using tiny electrical shocks that force your muscles to contract. You get a workout, they say, while you relax.

The claims say even Olympic athletes and bodybuilders use EMS to get those rippling muscles.

That's great, if it works. I'd love to trade in my exercise bike for an easy chair. But EMS sounds a lot like the fitness version of a free lunch. Could it possibly be true?

To find out, researchers from the University of Wisconsin at LaCrosse recruited student volunteers who were willing to get wired. Before the experiment began, exercise physiologists carefully weighed, measured and photographed the students. They also checked to see how much body fat each had and how strong the muscles in their arms and legs were.

For the test, the researchers purchased several $500 EMS machines from a company called Body Shapers. The students agreed to use the machines three times a week for eight weeks, taking as much of a jolt as they could handle.

For most, like Jared Korn, the process was just mildly uncomfortable. He said it was "like you're getting poked with a bunch of needles."

Another participant said, "It's an intense tingling feeling...like your muscles are just like, I don't know, going crazy."

Of course, the discomfort would be worth it if the machine delivered the promised results. But when the volunteers were re-tested after two months of regular EMS treatments, their muscles didn't measure up.

"After they spent 45 minutes three times a week for eight weeks, they are the same as when they started," said Karen Palmer McLean, co-author of the study.

Those results do not surprise the American Council on Exercise, which sponsored the Wisconsin study.

"You're not going to lose any fat and you're not going to gain any significant increases in strength or tone," says Richard Cotton of the American Council on Exercise.

"Bottom line: this is pure deception," he concluded.

Nobody from the company would talk to CBS News about the study results.

The American Council on Exercise pointout that whatever you get from these EMS machines is not real exercise. You would not burn the calories or get the aerobic benefits that come from exercising the old fashioned way.

EMS machines are sometimes used in physical therapy for people who have been injured or paralyzed. And athletes do sometimes use them in training, but in addition to exercise, not instead of it.