(Photo: Tom Schierlitz)
Admittedly, there’s something counterintuitive about the idea that less padding on your foot equals less shock on your body. But that’s only if we continue to think of our feet as lifeless blocks of flesh that hold us upright. The sole of your foot has over 200,000 nerve endings in it, one of the highest concentrations anywhere in the body. Our feet are designed to act as earthward antennae, helping us balance and transmitting information to us about the ground we’re walking on.
But (you might say) if you walk or run with no padding, it’s murder on your heels—which is precisely the point. Your heels hurt when you walk that way because you’re not supposed to walk that way. Wrapping your heels in padding so they don’t hurt is like stuffing a gag in someone’s mouth so they’ll stop screaming—you’re basically telling your heels to shut up.
And your heels aren’t just screaming; they’re trying to tell you something. In 2006, a group of rheumatologists at Chicago’s Rush Medical College studied the force of the “knee adduction moment”—basically, the force of torque on the medial chamber of the knee joint where arthritis occurs. For years, rheumatologists have advised patients with osteoarthritis of the knees to wear padded walking shoes, to reduce stress on their joints. As for the knee-adduction moment, they’ve attempted to address it with braces and orthotics that immobilize the knee, but with inconsistent results. So the researchers at Rush tried something different: They had people walk in their walking shoes, then barefoot, and each time measured the stress on their knees. They found, to their surprise, that the impact on the knees was 12 percent less when people walked barefoot than it was when people wore the padded shoes.
“If you can imagine a really big, insulated shoe on your foot, when you walk, you kind of stomp on your foot,” says Dr. Najia Shakoor, the studies’ lead researcher. “The way your foot hits the ground is very forceful. As opposed to a bare foot, where you have a really natural motion from your heel to your toe. We now think that’s associated with more shock absorption: the flexibility your foot provides, as well as a lack of a heel. Most shoes, even running shoes, have a fairly substantial heel built into them. And heels, we now know, can increase knee load.” Another factor, she points out, is that when your foot can feel the ground, it sends messages to the rest of your body. “Your body tells itself, My foot just hit the ground, I’m about to start walking, so let’s activate all these mechanisms to keep my joints safe. Your body’s natural neuromechanical-feedback mechanisms can work to protect the rest of your extremities. You have much more sensory input than when you’re insulated by a thick outsole.”
The same holds true with athletic shoes. In a 1997 study, researchers Steven Robbins and Edward Waked at McGill University in Montreal found that the more padding a running shoe has, the more force the runner hits the ground with: In effect, we instinctively plant our feet harder to cancel out the shock absorption of the padding. (The study found the same thing holds true when gymnasts land on soft mats—they actually land harder.) We do this, apparently, because we need to feel the ground in order to feel balanced. And barefoot, we can feel the ground—and we can naturally absorb the impact of each step with our bodies. “Whereas humans wearing shoes underestimate plantar loads,” the study concluded, “when barefoot they sense it precisely.”
Six students, of which I am one, have gathered in a studio at the Breathing Project in Chelsea, to learn how to walk properly. “Walking itself is the intentional act closest to the unwilled rhythms of the body, to breathing and the beating of the heart,” wrote Rebecca Solnit in Wanderlust: A History of Walking, and this is what we’re aiming for, more or less, as we circle the room slowly, in our bare feet, under the eye of our instructor, Amy Matthews. She’s a former dancer who now does private movement therapy, as well as teaching yoga, anatomy, and kinesiology classes as part of her Embodied Asana workshops. This is day two of a ten-week class on the leg that started, conveniently for my purposes, with the foot. Last week, Matthews showed the students how you should roll through each step as you walk, rather than simply clomping your feet up and down—a lesson that everyone is now struggling to apply. When Matthews asks the class how things went over the past week, one woman is not thinking so much about internal rhythms or the beating of the heart. Instead, she says, “I learned one thing: Walking’s hard.”