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Posts Tagged ‘barefoot running’

Do running shoes reduce injuries?

February 27th, 2011

This week’s Jockology column is now posted on the Globe and Mail website. It takes on a topic that’s reasonably familiar to readers of this blog: whether the “right” running shoes will reduce your risk of getting injured:

[…] “I was completely convinced that impact is something bad, and pronation is something bad, and I wanted to show that,” recalls Benno Nigg, a biomechanics researcher and co-director of the University of Calgary’s Human Performance Lab, who helped shape the original theory of pronation.

The initial studies were promising. Specialized running shoes, designed to address different degrees of under- or overpronation, could indeed reduce the impact forces shooting up through the legs of runners in lab testing. In the United States, sales of these high-tech shoes jumped from 25 million pairs in 1988 to 40 million in 2009, and growth was similar in Canada.

But there was just one problem: Running injuries didn’t disappear…[READ THE REST OF THE ARTICLE]

I also spoke to Michael Ryan, the researcher whose UBC/Nike randomized trial of different shoe types made a huge splash last year:

“We were a bit nervous, because … if you see someone who is highly pronated, putting them in a neutral shoe may be a recipe for causing more pain,” acknowledges Michael Ryan, the study’s lead author, who is now a postdoctoral researcher at the University of Wisconsin.

He needn’t have worried…

In terms of practical advice, the article ran with a sidebar that doesn’t appear to be posted online, so I’ll add it here:

Picking a running shoe
Shoe researchers Benno Nigg and Michael Ryan agree that comfort is a good starting point for picking a running shoe. Some other factors to consider:

  • You can only assess comfort by actually running in the shoe. Many running stores will allow you to run around the block or on a treadmill.
  • Don’t ignore fit in favour of fancy shoe features. Find a brand and/or model that fits the specific characteristics of your foot, such as width.
  • Dr. Ryan’s research suggests that heavier, bulkier shoes may be associated with more injuries. So all else being equal, choose a lighter shoe.
  • If you’re making a radical switch (trying minimalist shoes for the first time, for example), take it slow. Expect to spend four to six months adjusting to the new shoes.
  • If you’re currently running successfully in a certain type of shoe, stick with it!

What do we actually KNOW about running injuries?

February 20th, 2011

I’m a couple of weeks behind the curve on this, but I just wanted to highlight an excellent post by Pete Larson of Runblogger. He recently attended a conference/course on running injuries taught primarily by Blaise Dubois, and took the opportunity to write up a succinct list of 16 things we know about running injuries, ranging from the very basic to the fairly technical.

Part of the reason I liked it so much was that it was very balanced — not promoting big shoes, little shoes, or no shoes as the panacea that will cure everything. In fact, his fourth point is:

Most running injuries are overuse injuries that can be attributed to stubborn and obsessive runners doing too much too soon. In doing this, runners exceed their body’s stress threshold and something gives. The end result is an injury.

Just for kicks, though, I’ll quibble with one point. He writes:

One of the things that also came through loud and clear is that barefoot running is our default. It is how we evolved, and modern shoes are a change from that default. Thus, the burden of proof should be to prove that we are better off running in big, bulky shoes. People often seem to think that the notion that we should run in a way that emulates the barefoot gait is radical (whether actually barefoot or in minimal shoes), but in reality it’s what our species has done for nearly 2 million years prior to about 1970.

I understand the point, of course. But let me make a competing point: in the U.S. alone, according to Running USA, there were 25.559 million people who ran at least 50 times in 2009. Some 10.29 million of them finished a road race. They bought a total of 39.76 million pairs of running shoes. How many of those people went barefoot, or in minimalist shoes? I really don’t know — I wish I had the data. But I think it’s fair to say that the overwhelming majority of people who have grown up in a modern, western, convenience-filled, concrete-covered society and have taken up running without having relied on it as a primary form of transport throughout their childhood have done so wearing conventional running shoes. Does that mean barefooting or minimalism or forefoot striking is bad? Definitely not. But since we don’t have any answers yet, let’s be circumspect about applying the “burden of proof.”

Anyway, I’m just quibbling here. Pete’s post is great, and a must-read for anyone interested in the topic!

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Shortening your stride mimics the effects of running barefoot

August 23rd, 2010
Comments Off on Shortening your stride mimics the effects of running barefoot

Just got back from a fantastic canoe trip in Quebec (and yes, I caught more pickerel, along with a pike and a whitefish). While I was away, my Jockology column on how shortening your stride can mimic some of the effects of barefoot running ran in the Globe and Mail:

…a forthcoming study from researchers at the University of Wisconsin suggests that many of the benefits promised by barefoot running, including a reduction of the forces acting on knees and hips, can be obtained simply by taking shorter, quicker steps.

“We found very similar loading patterns,” says Bryan Heiderscheit, the senior author of the study, which will appear in a forthcoming issue of Medicine & Science in Sports & Exercise, “and you don’t have to go all the way to the extreme of getting rid of your shoes. [READ THE REST OF THE ARTICLE…]

I initially blogged about this study last month, but I subsequently had a really interesting interview with Dr. Heiderscheit. Obviously, this is a very controversial topic these days, and it sometimes seems as if everybody has a biomechanical study that supports their point of view. So I was happy to hear that the Wisconsin team is undertaking a proper randomized, controlled clinical trial that will follow runners for a year or two as they alter their stride length, to see whether it actually affects injury rates as opposed to just joint forces.

Orthotics for knee pain: does pronation matter after all?

August 5th, 2010

After last week’s discussion of the presumed death of the “pronation control paradigm,” I came across this new Australian study posted online at the British Journal of Sports Medicine about using orthotics to combat patellofemoral pain syndrome (PFPS — the nasty affliction sometimes known as “runner’s knee”).

The basics: 52 volunteers suffering from PFPS were given off-the-shelf three-quarter-length orthotics to insert in their shoes, with “built-in arch supports and 4 [degree] varus wedging.” They were then immediately tested to see whether they had less pain and could do more single-leg squats, step-downs and rises from sitting. The results:

Prefabricated foot orthoses produced significant improvements (p<0.05) for all functional outcome measures.

Hurrah! But here’s the rub:

A more pronated foot type and poorer footwear motion control properties were found to be associated with reduced pain during the single-leg squat and improvements in the number of pain-free single-leg rises from sitting when wearing foot orthoses.

Hold on, I thought we decided pronation and motion control don’t matter because they were just invented to make money for shoe companies! But that’s not what the authors think. In fact, they conclude that

foot orthoses have greater effects in poorer-quality shoes, possibly as a result of a greater potential to improve motion control properties.

Let’s step back for a moment. This study has a lot of limitations, not least of which is the fact that it wasn’t blinded, randomized or controlled. Also, if you look closely, the results are rather mixed. For step-downs, 57% got better, but 27% got worse; for squats, only 38% got better, while 20% got worse. Is this because orthotics made pronators better and supinators worse? Maybe… sort of… but not quite. Even the researchers had to waffle a bit in their discussion:

Although supportive of traditional theory, the associations of foot posture and change in foot posture with functional improvements were only fair.

So what can we take from this? Well, this study certainly doesn’t “prove” the pronation paradigm. But the fact that more than half the people in the study got immediate relief from a shoe insert tells us that monkeying around with joint forces is capable of affecting running injuries, for better or worse. Now, if you put those knock-kneed, flat-footed volunteers on a minimalist program, it’s entirely possible that they’d compensate for their weaknesses and imbalances and get rid of their knock knees and flat feet — eventually. Proper shoes, on the other hand (or in this case, orthotics), seem to cure the problem for some people immediately.

In a perfect world, we’d all be patient, careful, and dedicated to our exercise regimens — and no one would need running shoes. But this study suggests to me that the pronation control paradigm is able to offer quick fixes to some people, in some circumstances. As a result, while I expect the minimalism trend to continue to grow (and I’ll be glad to see that), I also don’t expect current running shoe technologies to disappear. Not because shoe companies are evil, but because some people will continue to want what those shoes can offer.

Running shoes, injuries, and the Great Nike Conspiracy

July 28th, 2010

Over the last week, there has been another bubble of excitement about the impending demise of conventional running shoes, spurred by the publication of a couple of studies that found no reduction of injuries when runners are fitted with shoes specific to their running stride — “motion control,” “neutral,” “stability” and so on. Gretchen Reynolds at the Times does a nice job of summing up the studies.

These are important studies. But I found the reaction to be a bit overblown, in some cases. Chris McDougall, the author of Born to Run, wrote a blog post with the title “Breaking news from Nike: We’ve been talking a lot of crap, and selling it,” calling the results “mindboggling and explosive stuff.” I don’t think he can be referring to findings themselves — he wrote a book on this stuff, so there’s no way he doesn’t already know that there’s never been a study linking shoe choice to injury rates. What he finds so  amazing is that one of the co-authors of one of the studies works for Nike. (It’s actually Gordon Valiant, who figured in a blog post just last week.) To him, this is evidence that Nike is peddling stuff that it knows doesn’t work.

Another point of view comes from blogger Pete Larson. In his initial summary of the research, he also marvels at this apparent contradiction:

Makes one wonder if the shoe makers actually have “proprietary data” supporting these designs, or if the whole pronation-control shoe paradigm is nothing more than a giant marketing gimmick.

Larson followed up a day later with another post titled “What is Nike doing? Speculation on a Shoe Market in Motion,” which I think is more on the money. In that post, he notes that “the questionable benefits of pronation control shoes have been present in the scientific literature for some time now (see this 2001 paper by expert biomechanist Benno Nigg).”

Here, for the record, is a list of the footwear companies that have employed Nigg’s consulting services, including Nike, Adidas and Mizuno. All the major shoe companies are perfectly aware of the strengths and weaknesses of current shoe research, and they all fund studies trying to learn more. It certainly looks like what Larson calls the “pronation control paradigm” is due for revision, as more than one shoe researcher has acknowledged. (Asics consultant Simon Bartold, for instance, told me earlier this year that Asics has completely abandoned the concept.)

The question is, what do we replace the pronation paradigm with? Nigg’s advice is to run in a shoe that feels comfortable to you — his group has produced some interesting studies suggesting that your body “knows” what will help it minimize the energy needed to stabilize your muscles.

To Larson (and McDougall, needless to say) the answer is even more obvious: “Your body evolved to run long distances, and it evolved to do so barefoot.” On the surface, it’s hard to disagree with this statement. But if you’re asking “What shoes are best for recreational runners in modern Western societies?” rather than “How did our ancestors run 100,000 years ago?” then I’m not sure we can assume the answer in the absence of studies. The barefoot/minimalist argument is extremely logical and makes a lot of sense — exactly like the “use shoes to cushion feet and reduce biomechanical forces” argument was in the 1980s and 1990s. Let’s not fall for the same mistake again by skipping the part where we check that the idea actually works in the real world.

[AUG. 5 follow-up: orthotics study suggests there’s life in the pronation paradigm after all.]

Can biomechanical analysis cure Dathan Ritzenhein’s injuries?

July 21st, 2010

Dathan Ritzenhein just announced that he’ll be running the New York City Marathon this November, joining a stacked field that already includes Haile Gebrselassie and Canadian hope Simon Bairu. One thing that jumped out at me from the press conference (as reported by Letsrun) was his coach Alberto Salazar’s assertion that Ritz’s injury problems are a thing of the past thanks to some high-tech analysis:

“Gordon Valiant – the head of biomechanics for Nike – did an evaluation of Dathan and was able to find some things that are unique to Dathan with the way he runs and strikes his foot. With that (study completed), we now have some modified inserts. I wouldn’t call them orthotics – just an insert into the shoe where he has an abnormal amount of force near his third metatarsal. It seems to have alleviated his symptoms completely and we’ve retested him in the lab and shown those forces have been lessened tremendously.”

For those who’ve been following the barefoot running debate, this should raise some flags. For years, critics of the big shoe companies have pointed out that measuring forces in a lab setting doesn’t necessarily equate to a change in injury rates. Australian minimalist advocate Craig Richards said as much in an article I wrote back in 2008:

“Shoe researchers and manufacturers will try and bamboozle you with the results of hundreds of biomechanical studies,” [Richards said]. While these studies tell you how your stride is affected by the shoe, “they cannot currently tell you what this means for either the injury risk or performance of the wearer.”

Fair point — though, as I pointed out last month, minimalists are suddenly more enthusiastic about biomechanical studies now that Dan Lieberman and others have provided them with some studies of their own.

Anyway, we now have a study (with n=1) in which the manipulation of biomechanical forces in the foot is hypothesized to solve a longstanding injury problem. The outcome measure: whether Ritz makes it to New York in one piece, with an uninterrupted build-up. Here’s hoping!

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Barefoot running and the difference between biomechanics and injury rate studies

June 7th, 2010

I just noticed that a short article I wrote for Canadian Running‘s May/June issue is now available online. It’s my attempt to provide some context for the studies on barefoot running that made lots of (somewhat wild) headlines at the beginning of the year. It doesn’t offer any definitive conclusions, mainly because I don’t think such conclusions yet exist. My main point is the distinction between biomechanical studies and injury-rate studies. Everyone has been beating up on the shoe industry for years because it relies on the former rather than the latter — but that distinction is suddenly being “forgotten” now that biomechanical studies supporting barefoot running are appearing.

A short excerpt:

[…] There’s no doubt that thinking on footwear has evolved in the last decade or two. For instance, plush cushioning is no longer considered the ultimate defence against injury. “I wish running companies would stop rattling on about ‘gel’ and ‘air’ and so on,” says Simon Bartold, an Australian shoe researcher who consults for Asics. Newer shoes reflect this thinking, he says: Nike has introduced the Free, for example, and Asics has completely abandoned the concept of “motion control.” But rushing to the opposite extreme and claiming that runners of all shapes and sizes should give up shoes makes no sense either – and the new studies certainly don’t support this position. […]

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National Magazine Award nominations

May 6th, 2010

If you’ll pardon a little self-promotion, the nominations for this year’s National Magazine Awards were announced last night, and I was thrilled to pick up three. Two of them were for my piece in The Walrus about the neuroscience of navigation and how using GPS may be affecting our brains.

The third was for a piece in Canadian Running on evolution, barefoot running and injuries, including some interesting thoughts from Chris McDougall, the author of the bestseller Born to Run. (The piece was written last spring, before McDougall’s book was released and rocketed the topic into the public conversation.) I included a brief excerpt from the piece in a blog entry last summer, but now the full piece is available online for the first time here:

The giant screen at the front of the lecture theatre shows, in gruesome detail, a dissected bare foot connected through tendons to ten different muscles in the lower leg, all pulling in slightly different directions. Benno Nigg, a renowned professor of biomechanics who co-directs the University of Calgary’s Human Performance Laboratory, is leading an audience of Australian academics gathered at the University of Sydney through a presentation titled “The Future of Footwear.” During almost four decades as one of the world’s leading athletic shoe researchers, Nigg has worked closely with major companies such as Adidas, Nike and Mizuno. But plotting the future of the running shoe, he now believes, may require a look to the past, at what worked for our ancestors.

“Look at all these muscles here,” he says, gesturing at the dissected ankle. He asks the audience to guess which of the muscles we need in order to walk while wearing a typical shoe. Only two of the ten are needed, it turns out: the tibialis anterior (shin) and the triceps surae (calf). “And all the other ones, you don’t need, because the shoes take over.” Nigg pauses to let his audience consider this piece of trivia, then poses the central question of his talk: “Is that a problem?” [READ ON…]

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If heel-striking is so unnatural, why do apes do it?

February 14th, 2010

In the wake of Dan Lieberman’s foray into the barefoot running debate, there’s an interesting counterpoint in the newest Journal of Experimental Biology from David Carrier of the University of Utah — the man who anticipated Lieberman’s 2004 “endurance running” evolutionary hypothesis by 20 years.

muybridge-walkingIn a nutshell, Carrier’s paper points out that heel-striking — a.k.a. “the devil,” as far as Lieberman is concerned — actually has advantages in some contexts. As the Utah press release puts it:

Humans, other great apes and bears are among the few animals that step first on the heel when walking, and then roll onto the ball of the foot and toes. Now, a University of Utah study shows the advantage: Compared with heel-first walking, it takes 53 percent more energy to walk on the balls of your feet, and 83 percent more energy to walk on your toes. […]

Economical walking would have helped early human hunter-gatherers find food, he says. Yet, because other great apes also are heel-first walkers, it means the trait evolved before our common ancestors descended from the trees, [Carrier says].

The main point of the paper is that it’s curious that our foot anatomy is adapted to heel-strike while walking (i.e. we have a big, prominent heel), unlike most other mammals. But it’s a trait we share with all the other great apes, so it’s not something that was only created by the advent of thick-heeled modern shoes. As both Carrier and Lieberman have argued, many of our anatomical features seem to have evolved precisely to favour endurance running — but our heels, in contrast, seem better suited walking. This isn’t that surprising, the authors argue, given that both running and walking were likely essential to early hunter-gatherers.

Ultimately, none of this conflicts with the arguments put forth by Lieberman. Even if it’s natural to heel-strike while walking, the evidence suggests that early humans didn’t heel-strike while running. (Though the new study confirms earlier findings that there’s no difference in efficiency between heel-foot and fore-foot striking for running.) But as the barefoot running debate heats up, it’s interesting to note that heel striking has an evolutionary origin.

Lieberman says barefoot running is better than shoes

January 27th, 2010

This is going to make a big splash. A paper by Dan Lieberman — the Harvard anthropologist who made headlines with the argument that long-distance running was a key evolutionary driver in humans — in tomorrow’s issue of Nature argues that barefoot running is better than modern running shoes. Here’s how the Associated Press is reporting this story:

Harvard biologist and runner Daniel Lieberman had a simple question: “How did people run without shoes?”

The answer he got is: Much better.

At least running barefoot seems better for the feet, producing far less impact stress compared to feet shod in fancy, expensive running shoes, according to a study by Lieberman in Thursday’s issue of the journal Nature. The study concludes that people seem to be born to run—barefoot…

What great timing, you might think. After all, it was just last week that I blogged about Mark Plaatjes’ thoughts on barefoot running — and two of his key statements, which I agreed with, were:

4. There are no clinical trials that show an effect of barefoot/minimalist running for a prolonged period of time.
5. There are no research studies that prove that wearing traditional running shoes increases injuries or that barefoot/minimalist running reduces injuries.

So does Lieberman’s study fill this gap? No. What he found is that his subjects strike the ground with three times more force when they’re wearing cushioned running shoes compared to running barefoot. This is reminiscent of the study that made waves a few weeks ago (which I blogged about here) that made the convoluted claim that running shoes are worse than high heels. What we’re dealing with in both cases is very indirect measures that may or may not have some connections to the outcomes that matter to us — i.e. pain and injury. I really don’t care how many Newtons of torque my patella is feeling if it doesn’t result in any injury or discomfort.

Now, I haven’t seen the study, so I’ll be very interested to read it when it comes out tomorrow. But given the current wave of popularity surrounding barefoot running, I have a sinking feeling that this is just the beginning of the storm — we’re going to see a whole bunch of studies coming out, accompanied by press releases and news stories, that capitalize on this interest without really telling us what we want to know. Hopefully there are also people doing the long, painstaking, prospective research that would really shed new light on this question.

I don’t mean to sound too skeptical here. I think a lot of what’s said about barefoot running makes very good intuitive sense. If I was growing a batch of test-tube babies to create a distance-running army, I’d probably have them avoid shoes during their formative years to develop the stride we see in Kenyan runners.

But most would-be runners in the Western world are not starting from scratch — and the question of what shoe makes the most sense for a middle-aged, overweight neophyte is still very much open. Even staunch minimalists would acknowledge that running barefoot isn’t an instant miracle cure. (“If you change the way you run quickly ‘you have a high probability of injuring yourself,’ Lieberman says. In general, changes either in running shoes or distance should be no more than 10 percent a week.”)

That may well be true. My feeling, though, is that most people who are REALLY cautious and patient enough that they never change their weekly running distance by more than 10 percent a week will find that they’re able to run successfully in almost anything. It’s like (bear with me here) buying a house to get the financial advantages. We can debate until we’re blue in the face whether owning or renting makes more sense — but for many people, buying acts as a “forced savings” mechanism, since they no longer have any disposable income to waste. Maybe barefoot running acts in a similar way: it forces runners to be cautious and build up very gradually — precisely the approach that works best no matter what you’re wearing.