Slip into these shoes, and they will do everything from tighten your tush and prop up your posture to put a dent in cellulite.

At least that's the promise/premise.

In fact, some ads (many feature a scantily clad female's lean legs and buff backside) even suggest the "toning/shaping" shoes make the gym obsolete.

Game on.

But hold your laces.

Is this fad, fiction or truly fantastic for those seeking a fit-fix?

At this point, the jury is still out. And it probably depends on whom you ask.

Although the shaping shoe designs vary somewhat, they generally feature thick, rocker-like soles with pods or curves in the bottom that create instability or a similar effect to a wobble or balance board. That imbalance, shoemakers say, causes about 11 percent to 41 percent increased muscle activity in the legs, glutes and calves, and decreases heel impact with forward motion.

Teresa Kennedy swears by the effectiveness of the Reebok EasyTone fitness shoes,

"I own a pair, and honestly, I love them," she said. "I got them in early September last year, and I went on vacation with them, and by the end of (it), I felt like I'd been walking up hill all week."

According to employees at the Reebok store at Tanger Outlet, the EasyTones are so popular, there's been difficulty in keeping up with the demand.

At the Skechers store at Tanger, Jim McKee, store manager, calls the Shape-Up a top-selling shoe in the U.S.

"The idea is that you get in shape while you're walking, even while you're at work."

Jon Juarbe, a sales rep at Super Shoes, agrees that the toning shoes are popular, but he has also seen some returned as well, and he questions the fad factor.

"Your body gets used to them," he said. "It's like weight lifting, first you start with 5 pounds and then you do 10, and you have to keep increasing."

Han Simonis, manager at Secret Sneaker, which currently offers the Shape-Up, said the shoes sell well, and customers seem to indicate the footwear does what it's marketed to do.

But Dr. Bruce Williams, a podiatrist and a past president of the American Academy of Podiatric Sports Medicine quoted by CNN, says there is not much independent research on the shoes, and he believes that the increase in muscular activity touted to result from wearing the shoes isn't always beneficial … and in some cases, uncomfortable.

Manufacturers recommend new wearers don the shoes during normal activities, starting with short periods as the unique style may take some getting used to.

"I'm not a big fan of people relearning how to walk," Williams said.

Dr. Alan Tuckman, an orthopedic surgeon with Lancaster Orthopedic Group, agrees that there is not much verifiable information about shoemakers' fitness claims.

But he does vouch for the medical benefits of the rocker-style shoes he has prescribed for patients, based on their reports of a decrease in pain and symptoms.

However, rehabilitative shoes have been designed with curved soles to help people with foot and ankle problems by transferring workload away from joints and bones, not to address physical fitness and strength, he said.

"It's nice that this type shoe is now out there and accessible," he said, as in the past, patients seeking rehabilitative footwear would have to get specially made shoe modifications.

He warns wearers that with this style shoe, there is no "docking station, so you're constantly trying to find a center."

Of course, whatever the consensus, manufacturers are banking on success.

Forerunners of the trend were Chung Shi Shoes and Switzerland's Masai Group International, a pioneer in what it calls "physiological footwear." Masai's MBT (Masai Barefoot Technology: the product name was inspired by the Masai tribe of Africa) is dubbed the "anti-shoe."

Following in the footsteps of these shoes are versions of FitFlops, including mukluks, as well as Skechers Shape-Ups and the EasyTone fitness shoes. Avia entered the game with the AviMotion, and even Avon has gotten on board with the Curves fitness shoes.

Although there are toning shoes available for men and women, the sneakers are generally marketed more to the latter.

Cost, size and weight of the shaping footgear varies, but expect to pay at least $100, and at the higher end, up to $400. Avon sells its shoes for around $50.

The claim that the shoes will make the gym unnecessary is "far-fetched," said Pete McCall, an exercise physiologist with the American Council on Exercise.

"If you think about it, you'd think you'd work harder with these shoes," said Tuckman, "but I don't think it's a replacement for a good old-fashioned workout, any more than the Wii is."

The right fit

When looking for a pair of fitness shoes, the key is comfort.

One expert offers these tips:

• Regardless of the brand, seek the one that's comfortable to you.

• The shoe should have medium firmess, not too soft or hard.

• It should be somewhat bendable.

Source: Dr. R. Amadeus Mason, Emory Sports Medicine Center

sjurgelski@lnpnews.com