Is it possible for a parent to learn from a child’s mistakes? That’s what seems to be happening in the “toning shoe” market: Online claims made by granddaddy-of-them-all MBT (Masai Barefoot Technology) have been rewritten since mid-December, possibly in response to a cascade of legal claims recently made against manufacturers of other thick-soled shoes.

On August 25, 2010, California resident Venus Morga filed a class-action lawsuit against Skechers, makers of Shape-Ups, because she found that she “did not experience any of the benefits described in Defendant’s misleading ad campaign,” including “weight loss, firmer muscles, reduced cellulite, improved circulation, and improved posture.” But Morga’s substantive allegations go further than an attack on a “deceptive marketing campaign”: her federal district-court filing also states that “the scientific community has rejected [Skechers’s] claims” of enhanced fitness effects.

Handily, the burgeoning popularity toning shoes had earlier in 2010 led to a study commissioned by the American Council on Exercise (ACE), “Will Toning Shoes Really Give You a Better Body?” A series of exercise trials pitted three brands of toning shoes against a pair of standard running shoes. Researchers measured subjects’ “oxygen consumption, heart rate, ratings of perceived exertion (RPE) and caloric expenditure” along with muscle-group activity via electromyography (EMG). They found that “across the board, none of the toning shoes showed statistically significant increases” in any of the measurements, stating decisively that “there is simply no evidence to support the claims that these shoes will help wearers exercise more intensely, burn more calories or improve muscle strength and tone” through their foot-destabilizing designs. ’Nuff said, according to this preeminent nonprofit fitness organization.

However, corporate managers will say interesting things when a $1.5 billion market (according to one estimate) is at stake. A group president at Skechers USA fired back at ACE by telling MSNBC.com blogger ConsumerMan that the ACE study is “flawed, flimsy and based on junk science.” He pointed to the more than thirty studies that exist on toning shoes (see www.toningshoestudies.com for some examples). However, it is telling that the studies Skechers cites in its U.K. ads (which are, incidentally, no longer available on its American website) were apparently run by the company itself, as reflected in one “result”: “an average weight loss by our participants of 3.25 pounds” (emphasis added). Although this “result” sounds great, it is rather difficult to assess the true impact of wearing Shape-Ups when no control subjects (indeed, no control shoes) are in place.

Dicey science is at the heart of a similar case, filed after California resident Bistra Pashamova was injured while wearing New Balance’s toning shoes. Pashamova’s class action complaint alleges that the studies behind New Balance’s rock&tone and True Balance shoes are simply not valid. On January 3 of this year, Pashamova claimed in her class-action complaint that “none of New Balance’s purported scientific studies, if any, have been subjected to traditional scientific scrutiny, in that none of them was conducted by impartial, double-blinded third parties, and none was subjected to peer review or other methods traditionally used by the scientific community to ensure accurate results. Rather, these purported studies, if any, were commissioned by New Balance and, from their inception, have been nothing more than deceptive marketing tools. Further, actual scientifically sound studies have found that the Toning Shoes do not provide the benefits claimed by New Balance.” Sound familiar?

No stranger to the party, Reebok’s EasyTone shoes have also been targeted by consumers, twice in November 2010. One filer of an attempted class-action suit, Sandra Altieri of Massachusetts, doesn’t say why she was disappointed in the shoes, but she demands a “corrective advertising campaign” and that money be returned to those who believed Reebok’s claims and spent about $100 on them in the quest for a firmer butt and thighs. Reebok stands by its shoe in a statement to MSNBC.com: “Reebok has never claimed that by wearing EasyTone a person will burn more calories or that EasyTone is a ‘magic bullet’ that will replace exercise.” It’s certainly easier to claim innocence in terms of newly invented claims versus those that have graced one’s advertising campaigns in the past.

Surely those companies charged with making untrue statements will be toning down their rhetoric if they haven’t already. Ironically, it’s possible that the huge market for toning shoes wouldn’t exist if not for MBT, which is lawsuit-free as of this writing despite trumpeting “There can be only one true original” on its homepage. The Skechers spokeman implicitly acknowledged MBT’s claim when he told MSNBC.com’s ConsumerMan that “It’s very intuitive.… Walking on sand will be more effortful than walking on a hard surface.” MBT created their shoes in 1996, their website states, for exactly that purpose: to mimic the effects of walking barefoot in sand like the Masai. MBTs are patented, but apparently their curved, rocker-like sole was one model for the toning-shoe marketplace—hence one reason for the company’s keen awareness of “brand protection.”

If MBT wanted its “pioneering physiological footwear” to remain “unique” though, perhaps it should have left out the two most irresistible (and ultimately refutable) of its four claims: “MBTs activate and tone your muscles” and “MBTs help you burn more calories whether walking or standing.” In mid-December of 2010, this text appeared on the MBT website under the words, “Over 40 scientific studies prove the unique benefits that only MBTs deliver, here are some of the facts.” This text is now gone, replaced by unprovable, emotionally oriented statements like “enjoy the unique feeling” and the tagline “Love the way they make you feel.” MBT’s website and “benefits” video claim that the shoes will “generate muscle activity in the lower body,” which could easily be proved or disproved by EMG tests with or without the shoes—provided that the wearer is actively moving his or her own feet! The same could be said for the claimed “positive effects both when walking and standing.”

Even the heart of MBT functionality has been wrapped in a blasé-sounding claim, with another layer of protection supplied via a telltale asterisk: “The curved sole with its integrated balancing area requires an active and controlled rolling movement that can help the body to improve balance and posture while standing and walking.* … *As every individual is different, results may vary from person to person.” Which results? We can circle back to “increased muscle activity,” which we discover “leads to activation of neglected muscles, improved posture and gait and relief of back and joints” (though if you have a “history of unexplained falls” or other listed medical conditions, you would do best to heed MBT’s “Important Safety Precaution”). “Relief of back and joints” actually pertains to MBT’s other, non-fitness market: the one Skechers is warming up to with its Shape-Ups work shoes, complete with “aluminum alloy safety toe.” Nurses and other consumers—in reviews found all over the Internet—report that they can stand happily for twelve-hour shifts in “toning shoes.” These reports indicate a happy future for this market but not for skeptics.

The MBT website now states that its shoes “Tone your body” rather than claiming the more specific claim that the shoes “tone your muscles.” This latter claim has been taken out of MBT’s literature entirely. It was a wild claim that ended up getting the kids in trouble, so MBT was wise to rethink it.