Vibram, Vivo Barefoot, Softstar, and the other shoe companies making an honest attempt at creating a viable shoe alternative aren’t the only entities capitalizing off the nascent barefoot trend sweeping the nation (and I’m not referring to podiatrists, as much as they like to claim barefoot running will create thousands of new patients). Several shoemakers have taken the barefoot ball and run the opposite direction – down the path of more shoe and more meddling into how the foot works – claiming to have improved upon the near-perfection of the naked human foot with (get this) bulky odd-looking shoes that weigh more than traditional running shoes.
Foremost is MBT, or Masai Barefoot Technology. MBT makes the “anti-shoe,” which is actually an unsteady, unstable shoe with a squishy, conspicuous “rocker” sole. The sole appears to be about 2 or 3 inches thick, and the instability is actually a feature. Yes, the most popular backed-by-internally-funded-science example of barefoot technology is a shoe that forces its wearers to teeter around. Sure, you gain a few inches, but at what cost? Without having tried them (and I honestly don’t plan to), the very notion of simulating barefoot walking by wearing big clunky shoes perplexes and confuses me. Talk about digging a hole to put the ladder in to wash the basement windows! Same goes for MBT’s claim of “natural instability” being the key to “recreating the barefoot experience.” Just what is so natural about being unsteady on your feet? I always figured feet were there to anchor us to the floor and provide stability. In fact, it’s that haptic perception (actually feeling the ground) in our bare feet that gives the brain the signals it needs to distribute shock effectively – tossed out the window now with MBT.
Then there are Skechers Shape-Ups, which are pretty similar to the MBTs: “rocker” sole, big wedge of material under the heel to “promote natural walking,” deliberate instability. They tighten abs, firm butts, and destroy cellulite. Armed with the Skechers Shape-Ups, folks can “get fit without stepping in a gym.” I’ll agree that a gym isn’t necessary for fitness, but strapping on a pair of magic non-shoes and standing there, or walking around the mall hoping for artificial instability to kick in won’t do it.
Bosu ball addicts have successfully integrated balls into many facets of everyday life. At the gym, they do squats, deadlifts, and bicep curls while balancing precariously on bosu balls; at the office, they sit on large balance balls instead of chairs; at night, they wrap their bodies around massive rubber spheres instead of beds. Locomotion was their white whale, though. They tried attaching handles to balance balls for easy bouncing to and fro, but they looked a bit too much like female bonobos in estrus (go ahead and Google that). Well, Reebok’s new(ish) EasyTone line of shoes slays the whale. They’ve actually installed three miniature balance balls into the sole of each shoe (I’m not making this up), allowing wearers to recreate the natural, evolutionary sensation of walking on inflated rubber balls.
This revolutionary barefoot technology, according to its hawkers, compels the wearer to move. Walking and exercising become almost passive acts; the shoes apparently propel you down the street. All you’ve gotta do is be carried away on a couple of foot clouds. Heck, even standing at rest in these babies is a constant, imperceptibly effective workout for your entire body. Who needs to consciously work out anymore?
Maybe the absurdity of barefoot technology isn’t evident to everyone, though. Condemning a non-shoe that’s actually a shoe for claiming to recreate the barefoot experience seems “reasonable”, but it’s always good to back arguments up with empirical data. And all the barefoot tech peddlers claim to have research supporting their products, so it’s only fair that we on the “nay” side also use research.
The American Council on Exercise, a non-profit fitness certification organization, recently put the claims of MBT, Skechers, and Reebok to the test and released the results (PDF) to the public. It should be noted that though the ACE is a non-profit, their continued existence depends on the certification of trainers that would be out of a job if the shoemakers’ “get fit without trying” claims were true, so I can see where some hackles about bias could be raised. Regardless, let’s check out their findings.
ACE conducted two studies. The first subjected 12 active women to twelve 5-minute treadmill trials at varying intensities while wearing different shoes (MBTs, Skechers Shape-Ups, EasyTones, New Balance runners). Each woman tried each shoe three times: a 5-minute, 3 MPH walk at 0% grade; a 5-minute, 3.5 MPH walk at 0% grade; and a 5-minute, 3.5 MPH walk at 5% grade. Oxygen consumption, heart rate, perceived exertion rating (RPE), and caloric expenditure were all monitored.
While all values increased across the board in response to increased work intensity, no significant differences were found in response to the different shoes. They all performed about equally.
The second study had a similar initial set-up – 12 active women, the same four shoe choices, the same 12 treadmill trials at the same intensities – but a different focus. Instead of measuring exercise output, this study examined specific muscular responses. Electrodes were hooked up to measure EMG activity in the gastrocnemius (or calf muscle), the rectus femoris (quadriceps muscle), the biceps femoris, the gluteus maxiumus, the erector spinae (back muscles), and the rectus abdominus (abs). An initial test was run to determine the EMG in response to a maximum voluntary isometric contraction (MVIC); the study would use EMG recordings from the treadmill trials and compare them to the MVIC EMG.
There was no significant difference in muscle EMG activity across different shoe types. EMG activity increased in response to the increasing intensity of the treadmill trials, as is to be expected. ACE’s ultimate conclusion follows thusly: “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.”
All parties obviously set out to prove their point. ACE may have a dog in the fight, however convoluted it might be, and they ran a fairly limited study (small sample size, short duration), while the shoe companies have the obvious objective to sell more shoes and justify it by funding their own research. I’m immediately skeptical of industry-funded research that also happens to support the industry’s product, but that’s completely natural.
My take? I just find it all absurd, to be honest; a battle over which is the lesser of two evils. It’s like those studies purporting to show the benefits of “healthy” whole grains by pitting them against refined, processed grains. Or the study that showed ankle taping provides better ankle stability in people who wear athletic footwear, while completely glossing over the fact that athletes wearing no shoes and no tape performed best and evinced the highest level of foot position awareness (the key determinant in susceptibility to ankle sprains). Neither choice is optimal.
The standard running shoe (New Balance) performed similarly to the fancy barefoot tech. What can we glean from this? What does this say about the necessity of any footwear, let alone barefoot technology? You’ve got two bare feet at your disposal, and I think people should begin learning how to use them before giving up and relying on “barefoot technology” to save them.
Have you tried MBTs or copy cat barefoot/toning shoes? Share your thoughts in the comment board. Grok on!