Barefoot Is Better
Who do we wear shoes? It seems obvious; we expect that they help us avoid injuries and provide comfort. Maybe we should think of the injuries we are getting by wearing them.
The image of the barefoot person is usually of someone poor, deprived, lower-class, hick, unclean, redneck or something else unattractive. Shoes are a big business. Within that business, running shoes have become part status symbol, part science. Those images might change if a study by Daniel Lieberman at Harvard is taken seriously. PhysOrg summarized his paper in Nature in which he analyzed the physics of runners with and without shoes. Barefoot runners, he found, strike the ground differently. Their feet absorb the shock of impact by landing more on the arch and ball of the foot than on the heel. Shod runners tend to be heel-strikers. “Most shod runners — more than 75 percent of Americans — heel-strike, experiencing a very large and sudden collision force about 1,000 times per mile run,” the article explained. That shock travels up into the ankle, shin and legs. “People who run barefoot, however, tend to land with a springy step towards the middle or front of the foot.” This gives them a “more compliant, or springy, leg.” The impact of the heel strike is reduced in good running shoes. Still, it could lead to repetitive stress injuries.
Lieberman put his runners into an evolutionary landscape, but could not avoid using design terms:
The differences between shod and unshod running have evolutionary underpinnings. For example, says Lieberman, our early Australopith ancestors had less developed arches in their feet. Homo sapiens, by contrast, has evolved a strong, large arch that we use as a spring when running.
“Our feet were made in part for running,” Lieberman says. But as he and his co-authors write in Nature: “Humans have engaged in endurance running for millions of years, but the modern running shoe was not invented until the 1970s. For most of human evolutionary history, runners were either barefoot or wore minimal footwear such as sandals or moccasins with smaller heels and little cushioning.”
Lieberman warned that a runner wanting to switch to barefoot running has to ease into it. It takes a little time to get used to it, but it could be healthy. “By landing on the middle or front of the foot, barefoot runners have almost no impact collision, much less than most shod runners generate when they heel-strike. Most people today think barefoot running is dangerous and hurts, but actually you can run barefoot on the world’s hardest surfaces without the slightest discomfort and pain,” he said. “All you need is a few calluses to avoid roughing up the skin of the foot. Further, it might be less injurious than the way some people run in shoes.” He encouraged more research into the health benefits of barefoot running. For those interested in comparing the two modes, Lieberman and his colleagues have set up a barefoot running website.
Most of us are so accustomed to walking in shoes we could not imagine walking around barefoot a good deal of the time, except at the beach or around the pool, but there are a few who prefer it; they amaze the rest of us with how nimbly and painlessly they scamper about on uneven ground, rocks, and all kinds of terrain. You might be inspired by this story to try easing into some barefoot running, or at least kicking off the shoes a little more often around the house, if your family members will let you. You may only regret it when stubbing your toe on a chair. This experiment is also not advised for desert hikers or snow. When you think about it, though, most cultures throughout history have done pretty well without heavy shoes.
We didn’t need Lieberman’s little evolutionary fairy tale to make this an interesting story. “Once upon a time, Lucy told her children to grow arches in their feet, and millions of yeas later, they obeyed.” Nothing in his findings constitutes evidence for evolution; he just assumed it, and weaved a flat-footed tale around it. Regardless, his work on human endurance running (11/18/2004) remains one of the most interesting “human body” stories we have reported here.
Why must this evidence be forced into evolution? The real scientific work was all measurement and analysis of design on living runners. That design involves many integrated systems (circulatory, respiratory, muscular, skeletal, thermoregulatory, endocrine, and more) that could not have evolved in a stepwise manner, if you’ll pardon the pun. Those who prefer creation explanations will notice that the foot is very well designed for our upright stance, just as ape feet are well designed for their lifestyles partly on the ground and in the trees. Adam and Eve came complete with all their physical needs (this was, of course, before thorns). It doesn’t mean that shopping malls with their dozens of shoe stores are unnatural; human creativity and inventiveness is also evidence of our design. But we should distinguish between needs and desires. Perhaps some of our inventions are not as good as the original plan. Will there be barefoot Olympics again some day?