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If the 100-up isn’t the secret, what is?

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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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I’ve had some interesting e-mail exchanges over the last few days after I expressed my skepticism about the merits of the sudden enthusiasm for the 100-up exercise. Basically, my position was (a) sure, it’s a perfectly good form and/or conditioning drill, which is why it has been in pretty much continuous use for decades, but (b) I didn’t see any reason to think it was “the secret,” or any more useful than other form drills, simply because Walter George said he used it. The mere fact that someone is fast and does a particular drill is a pretty slender reed to build a training program on — and if that’s the yardstick, I pointed out to one person with tongue firmly in cheek, then I should be considered more qualified than Walter George to dispense advice, since I’ve run considerably faster than him.

Well, Justin called my bluff:

Great points all around [he wrote,] so here’s a question for you: if you had to start somewhere to learn running form — and you couldn’t afford a coach — where would you start?  What exercise would advance you the most in the shortest period of time?

That’s an excellent question. And a difficult one. So here’s my attempt to answer — or rather, to explain why I don’t have a simple, easy-to-package-and-sell answer.

The thing is, I’m still not convinced that most people do need to learn running form. I worry that all these articles about the necessity of learning the “one true way” to run are convincing people that they shouldn’t risk heading out the door in an untrained state to try this enormously complex activity.

Of course, some people definitely do need help with form. I watched the New York Marathon last weekend, and yes, there were some funky strides going past after the leaders were gone. So how do we fix those strides? Well, that depends on what’s wrong with them. Some people are leaning too far forward, others are leaning too far back. Many are overstriding, but a few are understriding. Some people are flapping their arms around like birds, others are barely moving them at all. It’s not the same fix for all of them.

Now, what Justin’s looking for isn’t a fix for a particular problem; he’s looking for a way to build the ideal stride from the ground up. And for that, maybe the 100-up is as good a place to start as any. I don’t have another exercise that I think is a “better” way to start developing a perfect stride, because I’m skeptical of the value of this perfect stride. In a sense, I’m just like Walter George in that I’m captive to my own experience and development. The way I learned to run was by heading out the door and trying it, then gradually adjusting along the way based on what felt good. That’s also how most of the people I know learned to run. Would we have been better if we’d been taught the “right” way to run right from the start? It’s possible.

By no means am I dismissing the benefits of optimizing running form. As I’ve written elsewhere, I think the single most common mistake people make is overstriding, which can often be addressed by quickening your cadence. I just have a nagging sense that form work has acquired enormous importance that is out of proportion to its value, when the real barrier for most beginning runners is still aerobic fitness. It reminds me of one of the most famous passages from Once a Runner:

And too there were the questions: What did he eat? Did he believe in isometrics? Isotonics? Ice and heat? How about aerobics, est, ESP, STP? What did he have to say about yoga, yogurt, Yogi Berra? What was his pulse rate, his blood pressure, his time for the 100-yard dash? What was the secret, they wanted to know; in a thousand different ways they wanted to know The Secret.

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Asker Jeukendrup on Gatorade and Geb

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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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While I was in New York earlier this week, I had a chance to chat with Asker Jeukendrup, the new “global senior director” of the Gatorade Sports Science Institute. After Amby Burfoot’s wide-ranging interview with him in September, I was curious about what that would mean both for his research and for Gatorade — which, as I wrote about in a Globe article back in 2009, had seemed to be moving away from evidence-based science and toward marketing gimmicks like adding theanine to “improve focus.”

So, after our conversation, I’m now at liberty to reveal… well, nothing. Asker promises that the Gatorade formulas will change, possibly in the short term but certainly in the medium term as new research directions yield results. What those research directions are he wouldn’t reveal, but he emphasized a shift from hydration to the full spectrum of performance nutrition. Two key focuses: energy delivery and recovery. What does this mean? His previous work on “multiple transportable carbs” (which he made famous for PowerBar) showed that the bottleneck for athletes trying to get carbs to their muscles is getting the carbs across the intestinal wall. My totally uninformed guess is that he’s looking at novel ways (different types of carbs? different molecular structures? different ratios?) of getting carbs across that barrier more quickly.

One other interesting nugget. A few months ago, I blogged about a study that included an unverified claim that Haile Gebrselassie lost 10% of his body mass due to dehydration during his world record marathon run. Jeukendrup has worked extensively with Geb — and though that data is confidential, I pressed him a bit about this claim. He confirmed that the 10% figure was reasonable. Geb’s a very small guy who’s capable of working at an inhumanly high work rate for an extended period of time. The result: he generates a huge amount of heat, and thus sweats a lot, likely more than two litres an hour. It’s not practically possible to drink anywhere near this much at world-record marathon pace, so Geb loses a ton of weight.

So the obvious question is: does this rather severe level of fluid loss hurt Geb’s performance? Jeukendrup’s guess: no. The primary mechanism through which dehydration might hurt performance is through reduced blood volume forcing the heart to work harder. But you can compensate for reduced blood volume to some degree: for example, your veins (which return the oxygen-depleted blood to the heart) contract, effectively shortening the circulatory loop. Geb’s example doesn’t prove anything either way — obviously it’s possible that he’d be a 2:02 guy if he drank more. But it’s hard to argue with a world record, unless we have some compelling reason to think that dehydration held him back (and I can’t think of one).

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Chris McDougall responds

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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: After a few further e-mails, it’s become clear that Chris misspoke in his original interview with me, and said he’d been struggling with plantar fasciitis for “two years” when he meant to say “two months.” This certainly makes a difference in my general sense of the extent to which it was misleading to write that he hadn’t lost a day of running to injury since then.]

I got an e-mail from Chris McDougall earlier today, asking that I correct what he sees as the errors in my post from a few days ago. Here’s his account of my errors:

there are several mistakes in your post about me. i’ve told the story of my bout with PF publically and often, as in the outside magazine interview below. your version is incorrect.

1/  i wasn’t “felled” by PF. in fact, i never missed a day of running because of it.during that period, i ran with many sources, including amby burfoot, matt carpenter, scott jurek, tony kupricka, david horton — all of them tough runners, most of the runs on hard trails.

2/ I didn’t have it for two years; it bothered me for a few months.

3/ i wasn’t ‘stressed out’ about it because the publication date was nearing; on the contrary, i was still researching and writing. i considered it a formative learning experience, which is why i’ve spoken and written about it many times.

4/ my training in 2006 was vastly greater than 2010/2011. in 2006, i hit 100 miles a week, including two 50-mile runs and several weeks of high altitude in leadville. last year, i averaged maybe 30 miles a week. i was traveling nearly non-stop, squeezing in whatever workouts i could manage.

Here’s an excerpt from the transcript of our interview in 2009:

Imagine the situation I’m in. Because two years ago, I start researching this book. And the whole purpose of the book, premise of the book is that I’ve discovered the secret of lifelong injury-free running. And in the middle of writing the book, I come down with this ailment. And I can’t shake it. And I’m thinking, you know, I’m about to go out and promote a book. And I got this stinking injury. And I spent two years [UPDATE: Chris misspoke and meant to say “two months”] trying to get rid of it.

His points number 2 and 3 are directly contradicted by that quote. Obviously I’m not inside his head (or his foot), so I don’t know which version is more accurate. But I think my original blog entry was a fair account of what he told me.

As for point number 1, I’m happy to believe him if he says he hasn’t missed a day of running due to injury since then. And I never said he did. But I certainly felt (and still feel) that the impression left by writing “I haven’t lost a day of running to injury since” is at odds with the fact that, during that period, he travelled (again, according to his 2009 interview with me) to see “doctors in Germany, in London, in Detroit, in Indianapolis, in California… all kinds of different people” in unsuccessful attempts to get rid of the injury. If that’s not being “felled” by an injury, I don’t know what is.

Finally, I’m not sure why he’s calling point number 4 an “error.” He suggested that his improvement from 2006 to 2010/2011 could be explained by his use of the 100-up. I suggested that an alternate (and in my opinion more likely) explanation was that he had four years of consistent running behind him, instead of one year of high mileage. Running is cumulative, and many runners experience episodes like this. Obviously I’m just speculating, as is he himself.

Ultimately, I’m disappointed by this exchange. As I said in the initial post, I think McDougall has a great story to tell that has resonated with a lot people. That story is strong enough on its own merits; it doesn’t need to be made better than it already is.

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Stats 101: interpreting medical studies

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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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I have a new article over at the Men’s Health website that tries to explain a bit about how the process of “statistical adjustment” works in large observational studies, and what some of the pitfalls are. My favourite example from the piece: a 2009 study of over half a million people that found that red meat intake is associated with increased risk of death — even after “adjusting” for potentially confounding factors like age, education, race, BMI, smoking, exercise, vegetable consumption and so on. Needless to say, that study got lots of press at the time. But when you dig into the study’s stats (as Stanford prof Kristin Sainani pointed out to me), you find out that red meat also increases your risk of sudden accidental death from causes like car crashes and guns!

“Unless red-meat eaters are swerving to avoid cows, that doesn’t make any sense,” Sainani says. Instead, the most likely explanation is that red-meat eaters take more risks in other areas of life. But the study didn’t collect any data on the driving habits and gun collections of its volunteers, so the researchers were unable to adjust for these factors—and as a result, the conclusions were skewed.

Another interesting nugget is a rough estimate of the size of effect needed to be fairly sure you’re not seeing the effects of residual confounding, according to statistical simulations:

Bad data can easily generate an apparent risk increase of up to 60 percent, according to a research paper on statistical adjustment published in the journal PM&R. Effects bigger than that are very difficult to explain without serious errors in the design of the study.

Anyway, check out the whole article for more!

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After New York: how did marathoners get so fast?

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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Another major marathon, another jaw-dropping course record — pretty much what we’ve come to expect in 2011. Geoffrey Mutai’s 2:05:06 at yesterday’s New York Marathon, a course record by 2:37, continues the string of unbelievable performances from Boston, London, Berlin, Frankfurt and so on that have redefined our (or at least my) perceptions about what’s humanly possible at this distance. For a great post-race look at what’s going with the marathon, check out David Epstein’s piece at Sports Illustrated (and for more background, read Ross Tucker’s Science of Sport piece from last week).

Epstein gives a nice overview of the various forces that are converging to give us all these 2:03 marathoners — most obviously money (more of it in marathons, less of it on the track), which is bringing talented runners to 42.2K earlier in their careers. But I just wanted to highlight two quotes from his piece. First:

“I think people are starting to figure out the training and physiology better,” said American Dathan Ritzenhein, who made his marathon debut in New York in 2006 at the age of 23 and finished ninth in the Olympic marathon in ’08.

And second (on the topic of whether all these runners moving to the marathon at a young age will end up having shorter careers than guys like Geb and Tergat, because of the inevitable physical toll of the distance):

Krista Austin, a physiologist who works with pro runners, thinks that this generation of young Kenyan marathoners will have a shot at long careers because “the Kenyans are just starting to do some of the basic [injury prevention] things, like stretching and massage and Pilates.”

The juxtaposition of these two quotes made me smile a bit. One on hand, Ritz saying that marathoners are getting faster in part because of greater understanding of physiology. On the other hand, Austin is correctly pointing out that the runners who are most obviously the fastest (the 20 fastest male marathoners of 2011 are ALL KENYAN) are barely taking advantage of even the most rudimentary suggestions of sports science. If we’re judging by results, we might want to think carefully about which approach we emulate!

Obviously it’s a very complex issue, and I won’t even get into the whole genes/environment question. But in addition to money, I think Epstein (citing Gabriele Nicola, the Italian coach of several of the top Kenyans) nails a vital point:

If one person can run fast, well, dammit, you can train or race with them, and you can, too. As much as we might say this is “in your head,” if it’s in your head, it’s in your body, at least within limits.