By ROBERT J. DAVIS
Special to THE WALL STREET JOURNAL
September 13, 2005; Page D4

It sounds like a strange contradiction: barefoot shoes. But two brands
of such shoes, Masai Barefoot Technology and Nike Free, are being
hailed by manufacturers as a way to strengthen muscles that aren't
taxed by normal shoes. Both supposedly improve athletic performance,
and MBTs are also said to increase circulation and reduce back pain,
among other things. Though each type of shoe has its enthusiasts,
there's limited independent, published research to back up the claims,
and foot doctors warn the shoes aren't right for everyone.

MBT's manufacturer, Swiss Masai, says the shoe is inspired by the East
African Masai people, who walk barefoot on soft, uneven terrain. As a
result, they have few back and joint problems, according to the
company. The MBT shoe has a multilayered sole with a rounded heel,
which creates an unstable feeling of walking on a ball or sand. To
stay balanced, the wearer is forced to use small muscles in the feet
and legs.

As these muscles strengthen, says the manufacturer, the load on the
joints decreases, resulting in less pain. The shoes are also claimed
to "lengthen" the body by improving posture and promote weight loss by
burning more calories. Some proponents say the shoes can even reduce
cellulite.

To make their case, MBT promoters often point to company-funded
research conducted at the University of Calgary. The study, which
included only eight subjects, concluded that MBTs result in more
muscle activity than standard shoes while the user is standing, and
less stress on knee and hip joints during walking. A recently
completed study by the same team suggests the shoes may reduce knee
pain in certain people with arthritis. Other small studies done in the
U.K. and Germany have found that the shoes positively affect posture
and gait. There's no credible evidence, though, that MBTs reduce the
appearance of cellulite.

MBTs are sold in a variety of styles, including sandals, sneakers,
boots and business shoes. They're expensive, running as much as $250
or more per pair.

Nike Frees, which cost $85 to $100, are targeted to a more limited
audience: athletes. Designed differently than MBTs, Frees don't have
an unstable sole but instead allow feet to move naturally as they
would without shoes. The idea comes from the experience of some elite
athletes and their coaches, who have found that training barefoot
helps increase strength and speed, and reduce injuries.

German research funded by Nike Inc., Beaverton, Ore., shows Frees
improve foot strength and flexibility when used during warmups. Some
foot doctors say the shoe may be fine for elite athletes but doesn't
provide enough support for the average runner. As a result, they worry
that Frees could cause tendinitis and other injuries like those they
see in weekend warriors who go running barefoot on the beach. Nike
says that there have been no injuries during testing and that the
shoes are safe when used as intended as a training tool.

If you decide to try Frees or MBTs, learn from a knowledgeable
salesperson how to use the shoes properly. Break them in gradually,
and don't expect them to reshape your body or cut your running time in
half. Remember that despite the claims, they are, after all, just shoes.

--With reporting by Debra Goldschmidt
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