More exercise better in long run

Biking to work is great. For me the hour spent commuting guarantees some sort of exercise 5 days/week and I can add to that with something else during the week or on the weekends. Its also a great way to wake up, and to get my mind in the right space before a day (or after). My only complaint - it can be hard to do in the -10c winter months up here in Canada.

I wholeheartedly vouch for P90X. After getting over the commercials, my wife and I bought the DVDs. We got results within four weeks. The challenge with that system is maintaining a high level of commitment to something that kicks your butt over the long term.

That seems like a net win to me; you get a lot of time to think when you're out running (which is to say it's not wasted time).

>"Unfortunately there's no explanation which means there's no science here."

Experimental science has a long and colorful history of answering the what before the how or why. Consider the question of black body radiation. Without the experimental research results and Plank's desperate attempts to fit them to a mathematical model, Einstein wouldn't have had a reason to think of light existing as discrete particles and theoretical quantum mechanics would not have possible.

Creating frameworks for why things work is satisfying, but gathering data is just as vital to science.

If you require more than a day to recover you should either be doing less strenuous exercise or you should be lowering your number of workouts per week.

I used to sit next to a 100+ mile/wk runner and he ate nothing out of the ordinary, just more of it (100miles of running is a 10-14k net calorie increase, depending on who you believe).

Almost every interesting and serious study regarding lifestyles is ethically and practically unable to be instantiated as a controlled experiment over the long term. Like many things, from studies of the economy, to social structures, to the climate. You can try to do a multivariate analysis, but ultimately you're not going to have much to go on. You have to take everything with a grain of salt, but it doesn't mean there isn't some valuable data in there. In addition, long term results are probably more interesting and important than short-term results; so much so that I would argue longitudinal studies are probably more useful than controlled studies, so long as one is careful and rigorous and vigorous with multivariate analysis after the fact.

>"Everything else I've ever read says exercise is dwarfed by diet when it comes to health, and the health benefits are pretty minimal to fitness beyond a pretty low threshold" <citation needed>

We've already been over this ground more than once:

According to one 32,000 person study in the American Journal of Clinical Nutrition (1999), "fit persons with any combination of smoking, elevated blood pressure, or elevated cholesterol level had lower adjusted death rates than low-fit persons with none of these characteristics". The same study found that aerobic fitness had a far more important impact on longevity than obesity did. This was cited in Fantastic Voyage, Kurzweil and Grossman, Chapter 22.

Another 100,000+ person study found that men who ran two or more marathons per year were 41 percent less likely to suffer from high blood pressure, 32 percent less likely to have high cholesterol, and 87 percent less likely to be diabetic than non-marathoners. Those who ran only one marathon every two to five years also had significantly lower risk for these conditions than non-marathoners. http://www.medicalnewstoday.com/articles/140104.php

Here's a different piece on how regular hour-long runs stimulate neurogenesis and memory improvements in middle aged humans: http://www.dana.org/news/brainwork/detail.aspx?id=7374

Distance running is one of the most beneficial things you can do for yourself. Racing marathons is also fine, with sufficient training.

By listing only negative effects, you can make anything sound bad (e.g. http://en.wikipedia.org/wiki/Dihydrogen_monoxide_hoax).

It doesn't seem crazy to think that there's such a thing as too much exercise, but there are a couple problems with this top ten list you cite.

First, maybe there are right and wrong ways to run a marathon and the people doing it the wrong way have skewed the results of these studies.

Second, if running a marathon is bad, then surely running half a marathon is still not good, right? What about a quarter-marathon? One mile? Etc. I think everyone agrees that there is some amount of running that does more good than harm. But it's not that helpful to simply say that marathons cause harm without looking at the good (if any) they do and then trying to find the distance that properly balances good and harm.

That list is pretty terrible. 4 runners of the Boston marathon got brain cancer over ten years? Over 20,000 people finished the Boston marathon last year (http://www.bostonmarathon.org/2009/cf/public/statistics.htm). Even if we assume it's the same 20,000 people running every year for ten years (highly unlikely), an incidence of brain cancer of 4/20,000 is the same as the incidence in the general population 15-20 / 100,000. (http://www.oncologychannel.com/braincancer/index.shtml). So, 4 people is about what you would expect. Given that it's not the same people, it's probably a good deal lower than the rest of the population.

It's pretty difficult to take anything on that list seriously if they're going to blatantly misrepresent statistics like that.

The only thing I need to know about marathons is that according to legend the first person to run one died! ;-)

See http://en.wikipedia.org/wiki/Pheidippides for details.

People reflexively downvote DeVany's observations to their own peril.

While some of that list is anecdotal, most is based on relevant studies, and on DeVany's long interest and observation of patterns of health (as an athlete and economist). His perspective is a necessary antidote to the popular conception that ever-longer distance-running delivers a monotonically-increasing level of healthiness.

DeVany suggests -- with evidence -- that instead, the optimal activity involves bursty, varied, intense exertion more than marathon-like exertion. The stresses and rhythmic pace of marathoning damage some systems more than they help.