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Chris McDougall on “the one true way” to run

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My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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[UPDATE Nov. 8 : Chris McDougall sent me an e-mail asking that I correct several errors in this blog entry. His description of the errors, along with my response, is here.]

I’ve had a few e-mails asking what I thought of Chris McDougall’s piece “The Once and Future Way to Run” in this weekend’s New York Times Magazine, so I figure I might as well share those thoughts here.

1. Chris is a great storyteller and an engaging writer. I really enjoyed Born to Run, and I enjoyed this piece too. I think the running world is better off now that there’s greater awareness of the potential benefits of running barefoot or in minimalist shoes, and people have another option in the search for a running approach that works for them. I’d go so far as to say that McDougall has done more than anyone else in the world over the past two years to bring new people to running and create excitement about its possibilities.

2. What about the science in the article? I can’t really critique it, because there isn’t any science there — it’s all anecdote. For a thorough and balanced take on what the science does (or, more accurately, doesn’t) tell us about the quest for running perfection, read Pete Larson’s response to the article. He’s the evolutionary biologist quoted in the opening scene of McDougall’s article. Larson’s cautious middle ground is probably not what you’d expect if you’d just read McDougall’s article without knowing anything else about Larson.

3. What about W. G. George’s 100-up exercise, a century-old drill that McDougall suggests may be the “one true way” to develop perfect running form? This is where I start rolling my eyes, when he attributes a series of personal best performances to this magic drill:

“I don’t get it,” [he says at one point in the article,] “I’m four years older. I’m pretty sure I’m heavier. I’m not doing real workouts, just whatever I feel like each day. The only difference is I’ve been 100-Upping.”

Oh, please. For one thing, four years ago was, by his own account, roughly when he finally “learned to run” for the first time. If he’d been unable to run for years, and then learned to run, his improvement now compared to four years ago is likely due to something we call “training.”

Incidentally, the 100-up is a drill that modern runners call the “running A.” Virtually every competitive runner I know has done it at some point, and it’s a basic staple of every elementary school track camp. I was first introduced to it more than 20 years ago. So does that mean that McDougall is right, that it’s the secret that makes good runners fast? Of course not. It’s one of the many, many tiny ingredients that can add up to running success. There’s no secret, and no short cut.

4. The one part of the article that made me kind of angry was this passage, about McDougall’s visit to the Copper Canyon in Mexico that led to Born to Run:

I was a broken-down, middle-aged, ex-runner when I arrived. Nine months later, I was transformed. After getting rid of my cushioned shoes and adopting the Tarahumaras’ whisper-soft stride, I was able to join them for a 50-mile race through the canyons. I haven’t lost a day of running to injury since.

I actually interviewed McDougall back in 2009, shortly before Born to Run came out. And that’s not the story he told me. Here’s what I wrote then:

Long plagued by an endless series of running injuries, he set out to remake his running form under the guidance of expert mentors, doctors and gurus. He adjusted to flimsier and flimsier shoes, learning to avoid crashing down on his heel with each stride and landing more gently on his midfoot. It was initially successful, and after nine months of blissful training, he achieved the once-unthinkable goal of completing a 50-mile race with the Tarahumara. But soon afterwards, he was felled by a persistent case of plantar fasciitis that lingered for two years. “I thought my technique was Tarahumara pure,” he recalls ruefully, “but I had regressed to my old form.” Now, having re-corrected the “errors” in his running form, he is once again running pain-free.

I’m in New York right now, and won’t be back home until Monday night, otherwise I’d see if I can dig up my actual notes from the interview. But I remember McDougall telling how stressed out he’d been, because he’d spent all this time working on a book about the “right” way to run — but as the publication date loomed ever nearer, he’d been chronically injured for two years. It was only shortly before publication that he was able to get over the injuries and start running again.

So does this prove that barefoot running is a sham? Of course not. Injuries happen, with or without shoes. But it points to a fundamental dishonesty in the way the story is being told. He’s not disinterestedly sharing with us the results of an experiment he performed on himself; he’s deploying all his rhetoric to make as convincing a case as possible for one side of an argument that (as Pete Larson explains) is much more nuanced than he pretends. I’m not a big fan of “science by anecdote” under any circumstances — but if you’re making up the anecdotes, then what have you got left?

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Dehydration in the lab vs. the real world

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My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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The “right” amount of hydration during exercise is a hot topic these days. For years, lab studies showed that if you forcibly dehydrate someone and then stick them on a treadmill, their performance suffers. But more recently, “real-world” studies (like the one I blogged about here) have shown that in many cases, the fastest finishers in races tend to be the most dehydrated. The difference, according to researchers like Tim Noakes, is that in the real world your brain is able to make pacing decisions that keep your body in a safe state (using the thirst mechanism); on a treadmill at a fixed pace in a lab, your brain is cut out of the loop.

The result is that there are two bodies of research — lab and field — that appear to be answering the same question (how much should we drink?) but that produce completely different answers. So it’s nice to see a study from the “lab” camp that tries to bridge this gap by doing some experiments on an outdoor trail run. Researchers from the University of Connecticut had 14 runners perform two 12K trails runs, one in a hydrated state and the other in a dehydrated state. Here’s what they found:

Pretty straightforward, right? The runners were slower when they were dehydrated. As expected. Case closed. And we should disregard those inconvenient studies that found that faster runners in real races are more dehydrated, according to the researchers:

Although some field studies have found runners to be extremely successful despite considerable body fluid losses, these runners were not compared with a control condition where these same runners remained more optimally hydrated. Therefore, one cannot conclude that performance in these elite runners may have been enhanced if they had maintained or at least attenuated some of their fluid losses while racing.

But hang on a sec. Does this new study really offer valid “field” conditions? Not quite. It may have been conducted outdoors, on nice trails in a local state park, but it nonetheless managed to reproduce all the usual problems of lab studies. First of all, the runners weren’t freely paced: they were instructed to run at a set heart rate, which imposes a rather arbitrary limitation. So they didn’t go slower because they were unable to keep the pace, but because they weren’t allowed to increase their heart rate. More importantly, the dehydrated runners weren’t allowed to drink or eat “high water content foods” for 22 hours before the test run! The result:

So what can we conclude from these results? If you subject volunteers to a punishing dehydration regimen before your experiment even starts, their performance will suffer. This is very important to bear in mind next time you’re stranded in the desert. But as for how much water you should drink during your next run, this study has basically nothing to say.

(I should point out that the researchers did measure a number of other physiological parameters in the study, like gastrointestinal temperature. This is useful data. They also argue that holding heart rate steady is useful because it’s “similar to how a cross country or track coach may advise their athletes to maintain a certain intensity level during a run.” Sure, I guess. But if that’s what they’re measuring, then why are they using the results to make claims about what happens in real-world marathons, where nobody starts after a full day of dehydration?)

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Average fitness has (surprise) increased since the 1970s

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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Here’s an interesting graph from a new paper from the Cooper Institute, the famous fitness institute founded by Kenneth Cooper, the “inventor” of aerobics:

The paper appears in this month’s issue of Medicine & Science in Sports & Exercise, and it shows the results of 52,785 fitness tests performed on men at the Cooper Institute between 1970 and 2009. Each patient appears only once in the data, so it’s not a longitudinal study of how individuals got more or less fit; it’s a cross-sectional study showing how the initial fitness of patients at the institute has changed over the years. The trend is pretty straightforward: a big jump from the 1970s to the 1980s, then levelling off to the 1990s, then a slight decline into the most recent decade.

So… at first glance, I found this data pretty surprising. My naive guess would have been that fitness (as represented in this graph by VO2max determined in an incremental treadmill test) would have declined steadily from the 1970s to the present. After all, we’re always hearing about how society has never been less fit. Instead, it seems that we’re fitter than we were 30 years ago, and other data in the paper suggests that we’re more active too. So does this mean that our current health woes have nothing to do with physical activity level? After all, the data also shows that average weight in the subjects has increased by 8 kg since 1970, while height has stayed the same. So we’re more active, but fatter — a pretty good indicator that diet, rather than exercise, is driving the rise in obesity.

Of course, there are a few caveats. For one thing:

Cooper Clinic patients are self-referred or referred by their employers and are primarily healthy college educated middle to upper income non- Hispanic whites who have access to medical care.

So there’s really no way of knowing whether the average patient who decides to go to the Cooper Clinic is comparable to the average patient from the 1970s. It could be, for example, that the clinic’s clientele has changed as it became famous, so that it now attracts people who are already a bit more serious about fitness. But that’s just speculation. The data may well be a fair representation of societal trends — and if so, I need to revise some of my assumptions.

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Yoga vs. stretching for lower back pain

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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I tend to post a lot about studies that find no benefits from traditional static stretching. Does that mean stretching has no benefits? No — it just means that the benefits are hard to quantify. So to be fair and balanced, I figured I should mention this recent study from the Archives of Internal Medicine, which suggests that stretching may be helpful for lower back pain (press releases here and here).

The study was actually designed to test whether yoga helps back pain. They compared a 12-week yoga program to 12 weeks of stretching (chosen to have a similar level of physical exertion), or 12 weeks reading a self-care book. Both yoga and stretching were better than reading the book at improving pain and function; there were no differences between yoga and stretching.

Now, I can’t help pointing out that the study isn’t immune to placebo effects. The assessments of pain and function were done with telephone interviews, and relied on subjective reports from the patients. And let’s be honest: the suckers who were randomized into the “self-care book” group knew darn well that they got the short end of the stick! So I don’t view this as strong evidence of a mechanistic relationship between stretching and back pain (i.e. that the back pain is caused by tightness in some specific muscle, and stretching releases the pressure to eliminate the pain). But that’s kind of beside the point. The stretching made people feel better — and for a very simple, low-cost, low-risk, uninvasive intervention (unlike, say, surgery), that’s a good enough outcome.

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Another reason for morning workouts: UV and cancer

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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Runners and cyclists (and walkers and open-water swimmers and so on) spend a  lot of time outdoors. Which is great — for me, that’s one of the big attractions! Still, that’s a lot of UV exposure, which is a bit worrying. But a neat and surprising study from researchers at the University of North Carolina, published in the Proceedings of the National Academy of Sciences, suggests that UV exposure in the morning is much less damaging than an identical dose of UV exposure later in the afternoon. This has nothing to do with cloud cover or sunlight intensity — it’s all about the body’s circadian rhythms.

The problem with UV light is that it damages your DNA; your body fights this ongoing damage by trying to repair the DNA. The levels of a key protein responsible for this repair process fluctuate during the day, with a maximum early in the morning and a minimum late in the afternoon. In contrast, the process of DNA replication, which can cause the errors in damaged DNA to spread, is slowest in the morning and fastest in the afternoon. So UV damage in the morning should be less likely to spread and more quickly repaired; in the afternoon, it’s the opposite. Here’s an illustration from the study’ s press release (you’ll notice that mice, which are nocturnal, have exactly the reverse pattern):

So does this effect have any real practical significance? Well, the researcher tested it on mice. They exposed two groups of mice to identical doses of UV radiation, one at 4 a.m. and the other at 4 p.m. The morning exposure group was five times more likely to develop skin cancer than the afternoon exposure group. (Remember that mice have the opposite cycle compared to humans, so that means morning is the best time to be exposed for humans.)

Is this sufficient evidence to tell people to switch up their exercise patterns? Not really. The researchers are now planning to directly measure DNA repair rates in human volunteers at various times, which would be another plank. For now, the timing of my workouts (which are, in fact, mostly in the morning) is dictated by lots of other factors — but it’ll make me worry a little less about the tan lines that I develop even when I’m running super-early in the morning. Now I just need a study that tells me that vitamin D production is maximized by morning sun exposure, and I’ll be all set!