Physician Warns of Risks Of Barefoot, Minimalist Running

CARMEL, N.Y. — Spring is here and runners are hitting the road.

Every year, 36 million people in the United States run and about half of them suffer at least one injury. To prevent injury, runners are advised to stretch properly, cross-train in other sports and, above all, to wear proper footwear.

Shoes come in for a good deal of the blame for injury and in the last couple of years debate about running shoes has been particularly heated, focusing on 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,” said Dr Alan Berman, podiatrist with Somers (N.Y.) 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 and the potential for injury.”

The barefoot revolution was sparked by the publication in 2009 of the best-seller Born to Run by Christopher McDougall. Mr McDougall tracked down members of the reclusive Tarahumara Indian 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 United States.

Noting the thin-soled sandals (called huaraches) worn by the Indians, he argues that the modern cushioned running shoe developed over the last 30 years is largely responsible for running injuries. 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, which are distinguished by individual pockets for the toes, Nike Free, New Balance Minimus, and models from Vivo, Inov-8, and Newton.

“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,” said Dr 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. And, of course, the new shoes are much lighter, generally in the six- to ten-ounce range for a man’s size 9, as opposed to the ten- to 13-ounce weight of traditional trainers.”

Proponents of barefoot running argue that the benefit of minimalist shoes is that because they remove cushioning, reduce heel lift and are less structured, they allow the foot to move more naturally and the runner to run as nature intended, resulting in stronger feet and leg muscles, improved running posture and reduced risk of injury.

But these benefits 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.

Habitually barefoot endurance runners land most often on the forefoot or the midfoot before bringing down the heel. In contrast, habitually 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 midfoot 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 Dr. Berman said, “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. In one study in which runners switched from traditional shoes to running barefoot or in minimalist shoes, only half of them adjusted their form, as recommended, to a forefoot strike pattern.

The other half kept the same form, landing first on their heels. Those who used the correct form experienced lower-impact forces on the foot but among those who did not change their form and continued to land on their heels, the impact forces created by barefoot and minimalist running were nearly twice as high as in regular athletic shoes.

“The bottom line,” Dr Berman concluded, “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. Further, we are all different in our biomechanics, our daily activit,y and our level of training or running experience. So a ‘one-size-fits-all’ approach is not appropriate and minimalist shoes certainly aren’t right for everybody.”