You’ve seen them on the running trails around town and at the gym: all those people wearing funky socks. (And no, we’re not talking about the way they smell.) The minimalist footwear trend has caught on with runners and lifters alike, for good reason.
A large and growing body of research shows that distance runners who are used to wearing shoes have an overwhelming tendency to hit the ground with their heels first. Despite the fact that traditional running shoes are designed to provide greater cushioning and correct pronation problems, heel striking by its very nature tends to shorten the runner’s stride. Moreover, it intensifies mechanical stress on the body: A study published in the journal Nature by Harvard University professor Daniel Lieberman shows that when distance runners remove their shoes, the peak vertical force at impact with the ground is seven times greater in heel strikers than forefoot strikers. About 75 to 80 percent of endurance runners are heel strikers.
Running barefoot or in minimalist shoes, however, removes the artificial architecture, allowing the muscles and supporting structures in the feet and lower legs to strengthen themselves. It also promotes forefoot striking, which translates stored energy in the calf and Achilles tendon into forward motion and has only one-third the impact force of heel striking. That means greater speed and fewer repetitive stress injuries. But the benefits don’t end there.
Did you really think all those photos of Arnold Schwarzenegger working out barefoot at Gold’s Gym in the ’60s were some kind of fluke? Golden-era bodybuilders sometimes preferred the feel of their feet against the gym floor on heavy lifts such as squats and deadlifts because they believed it built the supporting musculature of the feet, ankles and calves along with the rest of the larger muscles. This is a technique still employed by lifters today, but near-max loads should still be shoed — especially by those new to barefoot or minimalist footwear training — because of the incredible forces that come to bear on the bones of the feet.
As with all things weight training, it’s better to start small and work your way up. Jon Gaffney, a former University of New Hampshire wrestler, tried on his first pair of Vibram FiveFingers (one of the first “barefoot” shoes on the market) in 2008 and hasn’t looked back since. On the days he forgets to bring his FiveFingers to the gym, he’d rather work out barefoot or in socks than go back to wearing regular cross trainers. “I found my base was much more stable in my major lifts: squat, deadlift, front squat, the big compound moves,” he says. “My knees weren’t coming out over my toes as much. My back and hips were more aligned, I didn’t have as much pain, and I really felt I could drive through my heels more effectively on those big lifts.”
Being able to grip the floor or ground with your toes — whether in minimalist shoes or none at all — gives you automatic traction. And because minimalist shoes are designed to strengthen your feet and legs naturally, almost anyone can wear them. “Some people with super-collapsed arches find they’re uncomfortable,” Gaffney says. “I personally have used custom orthotics for pancake-flat feet since I was in middle school, and these are more comfortable than my orthotics.”
While some people like Gaffney may take to minimalist footwear right away, most people will require an adjustment period, and that goes double for heel-striking distance runners. Scientists and shoe salespeople alike recommend building up your endurance slowly when making the switch. For runners, Lieberman suggests wearing them for only 400 meters to a mile every other day for the first week, then increasing the distance by 10 percent a week as long as you have no problems. Stretch your calves and hamstrings regularly and massage your arches. “Always listen to your body,” Gaffney says. “If something is hurting or uncomfortable, back off.”