Can you firm and tone your butt simply by slipping into a new pair of shoes?

Reebok sure thinks you can. You’d have to be living in a cave somewhere not to have heard about the new Reebok Easy Tone walking shoe.

“Consumers are buying it — literally. Officials from Reebok, a unit of Adidas, say the EasyTone is the company’s most successful new product in at least five years,” according to the New York Times. But can it really be true? What makes this shoe so special that it can improve your level of health and fitness?

Basically the shoes integrate balance or bosu ball “balance pods” into the toe, ball and heel of the shoe. Reebok claims that this increases gluteal or butt muscle activation an average of 28 percent, in addition to stimulating hamstring and calf muscles 11 percent better.

So where do those numbers come from? A Reebok financed an exercise study involving five people. What, you say? The same New York Times articles reports:

“In that study, done at the University of Delaware, five women walked on a treadmill for 500 steps wearing either the EasyTone or another Reebok walking shoe, and while barefoot. Using sensors that measure muscle activity, the researchers showed that wearing the EasyTone worked gluteal muscles an average of 28 percent more than regular walking shoes. Hamstring and calf muscles worked 11 percent harder.”

They go on to report that Reebok’s head of advanced innovation, Bill McInnis, says the small size of the study was adequate and common among other studies of its type.

McInnis is more than Reebok’s head of advanced innovation; he’s also the scientist behind the EasyTone and a former NASA engineer. As air passes from one “balance pod” to the other, it feels to the walker as if she is walking on sand — which requires more work and muscle engagement than walking on pavement.

Despite Reebok’s tiny study and their alleged 15,000 hours of wear-test data, the long-term benefits remain to be seen. In a July 2008 study of instability boards and balls, Canadian researchers found that among experienced exercisers, moderate instability balls like the bosu had little effect on muscle activation.

As with many fitness gizmos and do-dads, the Reebok EasyTone may have more to do with a better mind-muscle connection than anything else. Even if that's the case, it should still have some initial effect — albeit a possibly small one — on the body.

Of course if you’re looking for a little eco-friendlier shoes to round out that green Christmas list, check out the fair trade sneakers from Veja or the New Balance 070’s. You may even decide to run in a green rund-raising race near you in 2010

Check out this advertisement for the Reebok EasyTone walking shoes. Yowza!