“I do think there’s a place for it,” she said. “We do some barefoot running and some running in Nike Frees, but it’s limited to warm-ups, drills, and cool-downs. The rest of the time I wear regular running shoes. I mean, I have an arch support built into my marathon flats! I know I need that support. I would be scared to run without it. I have a good feel for what I need, and I know that shoes help me.”
Having just finished work on a book about the mind-body connection in running, I am keenly conscious of how attuned the world’s best runners are to their bodies and their bodies’ needs. Last year I got to spend some time with Haile Gebrselassie at an adidas-sponsored event in Los Angeles. Geb spoke at some length about how much and why he loved the adiZero Adios racing flats he had set his latest marathon world record in, and why he liked them better than the previous shoe adidas made for him. The man really knew his shoes.
I was surprised to see Geb wearing an altogether different type of shoe, one of adidas’ heaviest trainers, on a short, easy run he led me and some other journalists on. Here’s a man who weighs 113 pounds, runs so lightly that I could not even hear his feet landing on a treadmill he ran on at 4:43 per mile (his world record marathon pace) six feet away from me, and is a true forefoot striker whose heels never, ever touch the ground, and yet he of all people trains in pillow shoes. Here’s a man who is so meticulous about his gear that I overheard him complaining to an adidas technical engineer about the side slits in his shorts not being deep enough, and of all the shoes he could choose for logging heavy miles it’s a pair with marshmallow soles. Here’s a man who grew up running barefoot and has no interest in going back!
Most advocates of barefoot running do not promote the practice as a means to run faster. Rather, they promote it as a means to prevent injuries, the idea being that shoes promote unnatural biomechanics that increase injury risk. Nevertheless, there is some cause to believe that running barefoot might in fact facilitate better speed. For example, a 2009 study by researchers at the University of Valenciennes, France found that even light running shoes reduced net running efficiency by adding weight to the foot and by allowing elastic energy to dissipate through the cushioning materials.
That’s not the whole story, though. Shoes affect race performance not only by affecting running economy but also by affecting the amount of vertical impact force the body absorbs (or at least how the body manages impact forces, as we’ll see below). Ryan Hall told me, “We race on the roads, which add much pounding to the body, which can be neutralized by the added cushion in shoes. Speaking from my own personal experience, I know which shoes have enough cushioning for certain distances. For example, I know that the Asics Hyperspeed 4 are the perfect marathon shoe for me but if I were racing a 5k on the road I would prefer the Asics Piranhas. You have to know what your legs can handle. If I were to race a marathon in Piranhas I can’t imagine how wrecked my legs would be and they still have some cushioning. To run a marathon barefoot with no cushioning would severely limit my performance.”
But exactly how would that added pounding affect performance? Sure, it’s less comfortable. However, couldn’t Hall and other elites just “tough out” that discomfort for the sake of gaining the economic advantage of going barefoot? Perhaps not, because the added discomfort and trauma associated with running barefoot might trigger a subconscious protective neural inhibition that would cause the runner to run slower. Indirect proof of this speculation comes from a recent study conducted at the Université de La Réunion, France. The authors of this study reported that subjects were only able to sustain 95 percent of their maximum downhill sprint speed in a set of 10 downhill sprints on a treadmill compared to 97 percent of their flat sprint speed in a set of 10 flat sprints. The researchers speculated that the additional eccentric loading of the legs that is associated with running downhill triggered a protective neural inhibition that caused the subjects to run slower relative to their maximal downhill speed. It seems plausible that the greater impact force associated with running barefoot might have a similar effect, at least in the later miles of longer races.
And let’s not forget that performance in races is affected more by the fitness that the runner takes to the starting line than by any small advantage in efficiency that is gained by the optimal footwear choice (including the choice of running barefoot). Kara Goucher, Haile Gebrselassie, and Ryan Hall each routinely run more than 100 miles per week. Could they absorb that kind of mileage as well if they ran barefoot, or even in very minimally cushioned shoes, instead of wearing the regular trainers they wear most of the time? They don’t think so.
The one problem with the “beating up the legs” theory is that the legs actually absorb roughly the same amount of impact force regardless of what kind of shoe they wear, if any, as the research of Benno Nigg, a preeminent running biomechanics and footwear expert at the University of Calgary, has shown. “What happens is that you change your style of running depending on whether you are wearing shoes or not so that the impact forces are always similar,” he says. When runners who are not habituated to barefoot running run shoeless, they reduce impact force by increasing muscle activation in the legs. Nigg grants that this increased muscle activation could account for the feeling of discomfort that runners like Goucher and Hall feel when running barefoot, but he doesn’t think it’s a big deal.
On that point, the evidence that it’s not a big deal whether (elite) runners wear shoes or not is more substantial than the evidence that either choice is better than the other. Nigg points out that Abebe Bikile won the 1960 Olympic Marathon in world-record time barefoot and won the 1964 Olympic Marathon in world-record time in shoes. Two footwear choices, one result.
But wait: Why did Bikila switch to wearing shoes? Perhaps for the same reason Zola Budd did. In a 2003 interview for Britain’s Guardian newspaper, Budd (now Zola Budd Pieterse) confessed, “When you’re young you can get away with anything.” She says she began running in shoes everywhere (she actually always wore shoes on paved roads) in response to recurring injuries, and that the change helped.
It is worth noting that most Kenyan and Ethiopian runners start running barefoot by necessity as youngsters but switch to wearing shoes at the first opportunity and then never voluntarily go back to running barefoot. Without question, having running shoes is a status symbol among young African runners, so that cannot be discounted as a reason for the switch. But Matt Turnbull, elite athlete coordinator for the Rock ‘n’ Roll Marathon Series, who has spent a good deal of time in Kenya and Ethiopia, tells me that the lack of running shoes is considered a significant training disadvantage there, not just a status disadvantage. In fact, it’s considered such an acute problem that organizations such as Shoe4Africa exist to address it.
What would happen if running shoes and all memory of them disappeared from the earth today? Let me answer the question this way: In high school my cross country teammates and I used to run some barefoot intervals on grass. While running one of them I stepped on the head of a spike being used to fix a soccer net to the ground and went down. The resulting bruise kept me out of action for a week. If running shoes and all memory of them disappeared from the earth today, things like this would start happening all the time. Before long an enterprising victim would get the idea to create some sort of protection for the foot. The running shoe would be quickly reinvented.
Perhaps the “first” running shoes would be little more than a tougher second skin. But inevitably someone would figure out that adding a little cushioning material seemed to provide an additional level of protection that made the logging of many miles on roads more comfortable. In a few years the running shoe market would undoubtedly look much like today’s. My point is that, while on a theoretical level it might not make much difference whether one wears shoes or goes barefoot, on a practical level, once you make a decision to use footwear simply to prevent traumatic injuries, frostbite, and the like (a decision that is itself practical), then you sort of have to see that commitment through and design and wear shoes that maximize all of the potential benefits of performance footwear while minimizing its disadvantages.
Ryan Hall makes the same point in a different way. “I am all for simplicity and getting back to functioning how us humans were intended to be,” he says, “but it gets dicey when you isolate one aspect of your running and not the entire lifestyle… If you are going to run barefoot because you say it is how we were intended to run, then I would say that is fine as long as you are going to go back to prehistoric nutrition, recovery (sleeping, resting, etc), and living (running on dirt roads instead of asphalt). I don’t think there were many prehistoric humans running around with beer guts.”
I don’t have as much at stake in my footwear decisions as Ryan Hall, but I am a competitive runner and I have a strong desire to perform as well as I can without making unrealistic sacrifices. As a matter of general orientation, I choose to pursue maximum running performance by emulating the practices of the world’s best runners, and especially the best American runners, because I trust that, since they have so much at stake, they are doing pretty much everything they can safely and legally do to run faster. I like science too, but I know that practice is always a few steps ahead of science in running, so when I see that elite runners continue to wear shoes for most of their training, that’s good enough proof for me that wearing shoes is, all things considered, the faster way to go.
Now, the argument that overbuilt running shoes tend to cause injuries is persuasive to me. That’s why I advise runners to wear the least running shoe they are comfortable in. But the consideration of comfort is as crucial as that of minimalism. Benno Nigg’s research has shown that injury risk is reduced and running economy is improved when runners select shoes by comfort. “There is a sort of body intelligence at work,” Nigg says, meaning that the feeling of comfort in a shoe is the body’s way of communicating that the design of the shoe is such as to enable the runner’s joints to move in their preferred patterns and minimize the amount of muscle activation is required to control impact forces.
As I suggested above, elite runners tend to be deeply in touch with their bodies and are smart enough to heed what their bodies tell them. Goucher, Gebrselassie, and Hall choose to wear what feels right, and what feels right for the majority of their running is regular training shoes. Since I crave speed as well, I do the same.
Of course, speed is not important to every runner, and that’s okay. The barefoot running movement is not really about speed. As Benno Nigg says, it’s really more of a religion. At its foundation is a very appealing ethos of naturalness and freedom, and now that the movement is fully formed, it also offers a sectarian sense of belonging, as my colleague Mario Fraioli observed in a recent article about a Vibram event in Boston. The reason I’ll never join this movement is that I care about speed too much, and I must confess that I see in it an element of Nietzschean ressentiment (hatred of the weak for the strong). I’d rather try as hard as I can to be fast and live with being 20 percent slower than Ryan Hall than latch onto barefoot running as a sort of sacred truth that allows me to feel superior to the unsaved shoe-wearing runners who kick my butt in races.[sgi:MattFitzgerald]