Monday, November 3, 2008

Art Devany Has No Clothes

I originally wrote this in early 2008, inspired by Art Devany's increasingly puffed-up sails. If you don't know who he is, briefly: he's a runner-phobic economics professor from UC Irvine who is best known for his exercise philosophy. Some of my statements below are relevant to comments that were being discussed on related message boards at the time. I expect a lot of hate mail from his disciples who Google me, but I also wouldn't mind reasoned discussion either.

Full disclosure: of course I am a distance runner, though I am not the Darth Vader distance freak that Devany assumes all distance runners must be. While I have run probably twenty marathons, I am certainly not a serious competitive marathoner, and I currently average 25-30 miles a week. This moderate program is not atypical even for repeat marathoners.

Devany frequently conflates claims that distance running is not the best workout for everything (which it's not) with claims that it actively hurts you; he has a clear and severe bias against running, to a point which makes me wonder if it's not associated with some tragedy in his life. Here are some major issues with Devany's claims:
1) Devany almost invariably provides examples of "extreme" runners who are champion marathoners or extremely high mileage runners who develop health problems. These folks are overdoing it or biting off more than they can chew.

I know a lot of other runners, and I don't know a single one who thinks it's a good idea to be like, or look like, the Paula Radcliffes and Alberto Salazars of the world; no one is surprised that the kind of training they put in hurts them. Similarly, a casual neighborhood softball league player doesn't get rotator cuff or knee injuries like many professional baseball players do (who overtrain), unless of course said casual player suddenly undertakes a major-league type training regimen (and bites off more than he can chew). Furthermore, there are many, many injuries that result directly from the type of training that Devany advocates. This is not an indictment of Devany; injuries can result from every type of training, Devany's included. I should add that after 17 years of distance running, the worst injury that has ever happened to me is a sprained ankle suffered when an air pocket blew out of a shoe.

In contrast, if a fifty year-old man hasn't trained adequately and keels over during his first marathon, he has no right to be surprised; just like I would be risking injury by jumping right into one of Devany's advanced upper-body regimens without building up to it. Extreme-anything hurts you, and under-training for any big athletic event hurts you. This should not be a revelation to anybody.

(2) Devany argues from an evolutionary standpoint, essentially boiling down to "when you behave in ways inconsistent with our hunter-gatherer heritage, you risk disease and injury". Evolutionary thinking is powerful, but it clearly does not support Devany's argument against distance running.

(Image credit to Alex Gregory and the New Yorker)

This idea is at base a good one and it's been around for awhile - in the 90s it was referred to as evolutionary medicine; it's also known in anthropology as the mismatch hypothesis, and in many cases it gives good results. Unfortunately, in Devany's case it falls apart on several levels. That is to say, the theory is falsified. To wit:

a) Hunter-gatherers frequently did go through periods of gorging themselves and starvation, forced on them by the whims of nature (otherwise how can you justify the fasting that is often part of Devanian regimens?) It therefore becomes difficult to argue that our ancestors would have adapted in such a way as to always require for optimum health a more discretely divided, continuous supply of good nutrition than most Americans now have. For example, the need to gorge occasionally is why we have a (now vestigial) appendix. Devany has claimed that eating a huge meal (like Thanksgiving) has a long-term negative impact on our metabolism. He either has to drop this claim, or get major points off the evolutionary basis of his theory (or just explain why something that happened to us constantly for hundreds of thousands of years would now start hurting us).

b) During a discussion on Devany's website about how distance-running was never seen among our hunter-gatherer ancestors, one contributor on his website (an anthropologist who had actually hunted with the classic hunter-gatherer Maasai) stated "I've actually hunted with the Maasai, and they run for hours after their prey," Devany's response was "No they don't. They stop and start." (I'm paraphrasing, but fairly.) So now we have Art Devany, Economist, and Fitness Guru, AND Maasai anthropology expert. Interestingly, his response is a classic economist position: either my theory is right, or my theory is right but your're giving me the wrong data.

c) One evolutionary theory for the growth of brain surface area during the evolution of hominids is that the brain grew to dissipate heat during running (the radiator hypothesis). This is evolutionary evidence that distance running is a part of our evolutionary heritage, not a perversion of it.

d) The Khoisan (less PC term, Bushmen) sometimes run for days to get to game herds whose dust plumes they see on the horizon. The Khoisan are studied by anthropologists precisely because they are thought to be the closest in lifestyle to our African hunter-gatherer ancestors. Again, it seems that distance running plays a part in our evolutionary heritage. And again refer to my comment about overtraining before: even the Khoisan don't engage in this behavior as much as Paula Radcliffe and Alberto Salazar.

e) There's also an Apache hunting technique of running down a deer for several hours until it's too tired to walk anymore. The technique works because deer (as animals) are not good distance runners, and we are. Again, the burden of argument is on Devany if he claims (as he must, to support an evolutionary basis for his theory) that the non-agricultural Athabaskan-speakers of the Four Corners area are atypical hunter-gatherers. Note that here I've pulled out three groups of people from two continents in only five bullet points, off the top of my head.

3) Many, if not most, cyclists and runners are cycling and running for different reasons that those for which Devany is exercising.

For many runners, it's a relaxation sport. For me, running is not "for" anything, except enjoyment for its own sake. It's my treat. It's like dessert to me. It makes me feel great, in a way I've never heard even one high-impact lifter say their workout made them feel. I don't have it on a to-do list, but rather I look forward to it all day. I would still do it even if I believed Devany's claims about its effects on my health, much like I know I shouldn't drink beer or go out in the sun without a hat. But both of those are fun too, and I enjoy running for its own sake.

And finally, I can't imagine how miserable it must be to equate your workouts with being indoors, and sitting on machines that have been sweated on for years, around other miserable people watching CNN on the screen in the corner, instead of in a gorgeous forest or meditating while you run through the mountains. Even Art said in one of his posts, "Run because you love it." Note that I'm not making an argument that running is a better training program than Devany's because I don't care. I would react the same way if you told me that I should stop drinking wine because it's not making my biceps bigger. It's just not relevant to my reason for drinking wine.


4) To put it bluntly: I don't know of any personal trainers who have offered me an analysis of the global credit market meltdown.

The truth or falsehood of Devany's assertions are ultimately independent of Devany's background - they're dependent on whether the data supports or falsifies them (and based on the counterexamples above, I think that's clear). Devany is an economist, not a physiologist. In fact he takes an Austrian school/libertarian viewpoint on economics that I happen to strongly agree with, largely because guys like Devany who know more than me about the subject often take that viewpoint and argue coherently, with data, in its favor. But in a nutshell, when a young specialist within a field of study contradicts received wisdom, s/he is often right; when someone from outside a field of study contradicts received wisdom, s/he is usually wrong.

A big red flag is that medically speaking, Devany's attempts at synthesis of already published exercise science results are highly selective and oversimplified to the point of being flat wrong. To wit:

a) He cites high CK levels in runners after marathons. The medical-jargon response to this is "Duh." CK is creatinine kinase, an enzyme fouund in muscle tissue. Finding it outside muscle cells (that is, circulating in your bloodstream) used to be regarded as evidence of a recent heart attack; now we look more specifically at the form of the protein that's found in the heart (CK-MB), but it's STILL not part of the differential diagnosis for cardiac trauma, that is to say, it's not meaningful enough that you include it as part of the observations required to conclude, "Yes, this person has had a heart attack." Know why it's so nonspecific? Your CK levels go up any time you do anything to exert yourself; the assay is just measuring damage to muscle fiber by looking in your bloodstream for an enzyme that normally exists only inside muscle cells (and therefore if you see it in the blood, all it means is that those muscle cells have been torn open). Guess what - after a lifting or tennis session, your CKs will be just as high. What's interesting is that the person who first explained this to me years ago was a cardiologist who was also a serious weightlifter, and he used the example of weightlifting as providing a false positive. And what's a little embarrassing about this is that it's common knowledge in sports medicine.

b) Devany likes to claim a link between running and brain cancers, and points out a high tumor marker rate in the blood of some marathon runners after a race. Here the mistake is cause-effect rather than specificity. Yes, the markers he cites are indeed used in cancer diagnosis, but in non-cancer settings they have no known link to cancer. That is to say, if you have cancer already, they're a good indicator of the severity of your disease; if you don't have cancer, there's no evidence that levels of these markers mean your cancer risk is higher. And these indicators are used for lots of other, non-cancer assays too. And even in cancer no one knows what most of them do (certainly not that they're causative or indicate some sort of pre-cancerous state). To illustrate by analogy: imagine a murder case that led to a conviction because the police officer on the scene found the still-warm gun in the suspect's car. Imagine the same officer later goes over to a friend's house and finds a still-warm gun in the shed, and accuses him of murder, regardless of the fact that the gun is sitting on top of a stack of used shooting-targets and (more importantly) no one has been found dead or turned up missing.

It's worth pointing out that pharmaceutical companies often use tricks like this when they have a drug with data that doesn't really bottom-line show that the drug does a good job of treating the disease. Their marketing people will draw your attention to some proxy indicator or pharmacokinetic endpoint and say, "You should buy our drug because it has the best concentration-over-time area-under-the-curve." Such claims are literally true and sound impressive, but it doesn't matter what else is going on as long as the competitor drug treats the disease better. You're interested in the outcome, not a proxy indicator that doesn't necessarily translate into outcome.

5) Heredity matters. A lot.

Devany jihadists often demand that I look at the results of his program. And indeed, Art Devany appears to be in good shape, especially for a man his age. Unfortunately for his theory and fortunately for him personally, he's probably just lucky (and the few such jihadists I know personally don't look as good). Many, many studies (here's one) have suggested strongly that genetics, not exercise and diet, is far and away the best predictor for obesity. We all know that there are people who stay lean throughout their lives, regardless of what they do, and Devany may well be one of those. Were other people in his family lean? I bet he had a good set of genes to start with. One of Devany's better-known advocates is Nicholas Nassim Taleb, who wrote Fooled by Randomness. It's an incredible book, and I would love to think more like Taleb; I would not love to look more like him. No, you can't count one guy as evidence against the theory, but you can't count evidence from one guy for it either.


Why did I write this article poo-pooing Devany's program? Because I've gotten tired of his disciples poo-pooing me for running. It's really getting very smug and even cultish; but in Devany's defense, the people I've encountered have been much more aggressive in their evangelism than he has been himself in interviews and on his blog. It really comes across as exactly that, evangelism, and it has almost religious overtones of "my way is the right way, and if you won't submit to the will of Devany the compassionate and merciful, you are morally inferior". So I'll say this: if people would rather do weights, squats, rapid-movement exercises in a gym, whatever, then that's fine. People exercise for different reasons. I know several people who do Crossfit training, and they don't enjoy it nearly to the degree that I enjoy running. Maybe they don't care; maybe that's not why they're in there, and that's fine too. I just ask that if you're part of this fitness subculture that you don't a) try to take away an enjoyable pastime from the rest of us who are actually happy with our exercise while we're doing it, b) try to generalize the health problems suffered by an over- and under-training minority to the activity as a whole, and c) dress up the theory in evolutionary and biomedical clothes that don't fit.

11 comments:

  1. Great Blog,
    I share your views. A while back I responded to Devany and his followers using excerpts from a book i was reading by Roosevelt, written during his hunting and species collecting while in Africa. Roosevelt clearly stated his amazement at how the Maasai would hunt by running their prey to death...by giving chase for days. Devany responded by saying that he owns a maasai spear and they would be too weak to throw the heavy weapon if they ran the claimed amount of distance. So I'm guessing that Roosevelt
    dreamed all this up. No point arguing that the body is actually hardwired for distance running because he won't buy into any of the solid data
    that doesn't support his view. I also tried to site a 73 year old marathoner who lives in my town named Ed Whitlock who holds multiple world records in several age categories. I see him running his 15-20k a day in the local cemetery. He's a machine, but Devany said he was too scrawny to throw a spear and would have starved to death in that scenario. At this point my viewpoint changed from supporter to skeptic. Your right when you say his approach is evangelical, that's the only other forum (religion) that I've experienced someone who refuses to see any perspective other than their own. I'm an avid adventure racer so running is a big part of my training and my life. Do it right and the rewards are off the charts. And most serious multi sport/triathlon racers I know have very well balanced and toned muscle definition. Ultimately, by having an objective viewpoint Devany would sell fewer of his DVD packages. Happy trails, keep up the miles, live long and prosper.
    Tom Bjelic (bjelic@cogeco.ca)
    Milton, Ontario

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  2. Great point Tom. I certainly don't begrudge people making money from their interests. If I could think of a way to monetize my blogs I'd do it in a second. But in Art's case, it does add further suspicion on the claims of someone who rejects out of hand any data that doesn't fit his pre-existing models.

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  3. DaVany is basically full of it. He really doesn't understand physiology, misrepresents data and studies, and generally is clueless about biology.

    Because of his rather amateur misguided attempts at exercise physiology I question even his statistical expertise.

    I would not waste my time criticizing DeVany. He won't accept another point of view on his rather silly apeman diet and life.

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  4. I think this will be my one post about him. I think the bottom line is that I would be just as suspicious of (well-known ultrarunner) Dean Karnazes if he started promoting eccentric economic theories about how to fix the credit markets.

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  5. Well done article, and I bet DeVany agrees but chooses to stress not running because so many people view it as a savior for total health, when really it's what you eat and being active. As much as I'd love it if we were like lions, who are truly the short burst animals, we are designed for a mix of steady running and high-intensity activity. Kudos for anyone who gets out and runs because they love it, it's a beautiful world and you don't get to see it lifting weights.

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  6. I am a big fan of Art DeVany. He is not an amature in biophysics.

    I am not dogmatic and certainly not religeous. But there is so much crap out there about health and exercise that I need scientific proof before I accept anything. And that is what Art is providing. He is a professor and capable of reading and interpreting scientic articles- even if it's not about economics.

    He must be at least 70 by now but looks much youger. He is fit and strong.

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  7. Anonymous:

    a) There are a lot of questions about exercise biology that aren't settled. We should look to exercise physiologists and nutritionists to settle them, not to economists, passionate though they may be.

    b) I make no quarrel about the shape that Art appears to be in, but as I mentioned, i) one physique does not an exercise theory make, and ii) I'll bet the rest of his family looks pretty damn good at that age too. Not all of us
    have good genes. This is why you need broader studies with big sample sizes; Devany unfortunately cherry picks, and said picking seems to be motivated by an agenda.

    c) In fairness to Devanians (including yourself), it seems the fundamentalists I encountered prior to this post are not representative of Devany fans as a whole. I've received no jihadis from his camp, though I welcome evidence-based counterarguments; bottom line, I still think that he's making claims that he mostly doesn't have evidence for, and he's motivated by an ideology.

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  8. "It makes me feel great, in a way I've never heard even one high-impact lifter say their workout made them feel..."

    I thought I was about to enjoy a well rounded discussion/arguement to a way of thinking that I am just exploring (evolutionary lifestyles/fitness), when you make this comment and lost me completely..

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  9. Andy, I think there are two possible interpretations of your statement here. One is that you're a paleo/high impact lifting guy and you do in fact have such a positive experience from your workouts. If that's the case, that's great, although based on my conversations around this topic with people on both sides of the fence, you seem to be in the minority - but if you feel this is incorrect please don't hesitate to correct me. The other possible interpretation is that you think this observation (that I enjoy my runs) is irrelevant to the discussion. If that's the objection, then I don't know what to say - I don't know how else we might assess relevance.

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  10. Following up on Andy's point: De Vany advocates short, intense workouts that are playfully nonroutine. He also says not to do reps until failure; you're basically training the brain to fail. Instead, he advocates fast lifts and slow lowering of weights, which tear the fast-twitch fibers (thus promoting their growth) to get a slight burn going.

    There's a sense of well-being afterward that doesn't quite match the runner's high, but is certainly worth it!

    I like your point about running as meditation, and as a spur to get out in nature. It's a way to feel good in this life!

    But De Vany's main concern is counteracting aging and avoiding chronic disease, and he summons acres of evidence when he gets down in the weeds of physiology, so to speak. I buy it. There seems to be a direct connection between muscle mass/body composition and the fending off inflammation-caused elderly decay.

    The Maasai example is a strong point, too; Art may be all wet in dismissing our ancestors' capacity for long runs. But I see a lot of value in his work, too. It's changed my life for the better!

    Thanks for a thoughtful critique.

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  11. Paul, thanks for your comment. Great that this post continues attracting comment after so long. I'm glad Devany's approach has worked for you. Another thing which I've thought about since I posted this but which I don't know if there's any literature on, is differing exercise response based on type of exercise. To some degree I think each of us will find the workout that we respond best to, and keep doing that. Certainly overall response to any exercise does definitely differ between individuals. So it may be that lifting (or running) doesn't build lean muscle and/or have the same mortality/illness avoidance benefits for each person.

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