WESTCHESTER COUNTY, N.Y. - Every year, some 36 million people in the United States go running -- and about half of them suffer at least one injury, according to the U.S. Library of National Medicine. In many cases, shoes wind up being the culprits.
In the last couple of years debate about running shoes has been particularly heated, and has focused on running in cushioned shoes versus the merits of running barefoot or in “minimalist” shoes that mimic running barefoot.
“For 30 years, there has been very little structural change in running shoes,” says Dr. Alan Berman, podiatrist with Somers Orthopaedic Surgery & Sports Medicine Group. “Now runners and shoe manufacturers are jumping on the barefoot bandwagon with dramatically different designs that have serious implications for runners' form, as well as for the potential for injury.”
The so-called barefoot running revolution was sparked in 2009 by by Christopher McDougall’s bestselling book, “Born to Run.” McDougall tracked down members of the reclusive Tarahumara tribe of the Copper Canyons in Mexico to find out how they could run a hundred miles at incredible speeds without suffering the routine injuries that plague runners in the U.S.
Noting the thin-soled sandals (huaraches) worn by the Tarahumaras, McDougall argues that modern cushioned running shoes developed over the last 30 years are largely responsible for running injuries. And as the craze for running barefoot or nearly barefoot has gathered steam, shoe manufacturers have introduced designs to suit. Among the most popular are Vibram FiveFingers, distinguished by individual pockets for the toes.
“The most important difference between traditional running shoes and the barefoot or minimalist shoes is that the new shoes have minimal padding on the bottom, sometimes as little as two-to-three millimeters,” says Berman. “They also have a lower heel-to-toe ramp angle, allowing the foot to sit almost level in the shoe, and they have less stride-controlling structure, that is, they don't correct for pronation, the inward roll of the foot with each step. The shoes are also quite a bit lighter, he adds.
Proponents of barefoot running argue its benefits include allowing the foot to move more naturally and the runner to run as nature intended, both of which result in stronger feet and leg muscles, improved running posture and reduced risk of injury.
But these benefits, says Berman, are predicated on the fact that people run differently barefoot than they do while wearing shoes and minimalist shoes are designed to accommodate barefoot running form. So runners who switch to minimalist shoes without changing their form are likely to suffer more, rather than fewer injuries.
Barefoot endurance runners land most often on the forefoot or the mid-foot before bringing down the heel. In contrast, shod runners land on the rear of the foot, facilitated by the raised and cushioned heel of the modern running shoe.
Proponents of barefoot and minimally shod running say heel-striking produces destructive forces on feet, knees and hips, and some studies have claimed reductions in knee injuries through barefoot running. But traditionalists claim forefoot and mid-foot striking put more strain on the calf and Achilles tendon, and there has been an increase in those injuries as well as anecdotal reports of stress fractures in barefoot running converts. As Berman says, “It may be that barefoot running isn't eliminating injuries but just changing their location.”
Runners are likely to run into trouble if they change shoe styles without changing running styles. “The bottom line,” Berman says, “is that the body clings to what it knows. Changing shoes doesn't mean you will automatically run in proper barefoot form. Many new barefoot runners continue to stride as they always have, landing heavily on their heels but without the cushioning of their usual shoes, which increases their risk of injury.”
As with most elements of daily life, a one-size-fits-all approach does not a solution make. “Minimalist shoes,” says Berman, “certainly aren't right the right fit for everybody.”