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- Alex Hutchinson (@sweatscience)
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This is a neat paper on how running affects the mind, with a surprise twist. (Check out Frontal Cortex and Neurocritic for more detailed discussions.) Researchers at Columbia University wondered whether the extreme stress of running a marathon might trigger hormones in the brain that would temporarily alter how our minds work. It’s a reasonable assumption:
Indeed, [the researchers write] cortisol levels recorded 30 min after completion of a marathon rival those reported in military training and interrogation (Taylor et al., 2007), rape victims being treated acutely (Resnick, Yehuda, Pitman, & Foy, 1995), severe burn injury patients (Norbury, Herndon, Branski, Chinkes, & Jeschke, 2008), and first-time parachute jumpers (Aloe et al., 1994).
So does running disrupt your memory? Yes. The researchers tested Boston and New York marathon participants, either a few days before their race or within 30 minutes of finishing, and the post-race tests showed worse performance on a set of verbal memory tests. That’s an example of “explicit memory,” where you consciously remember events and facts. But here’s the surprise: the researchers also found that the post-race testees did better on tests of “implicit memory,” which is how you store information that you don’t need to access consciously, like how to ride a bike.
In other words, it appears that being under stress (and marathons definitely count as stress!) causes you to tap into the older, reptilian part of your brain, where instinct and intuition dominate.
[Thanks to Kyle for the tip. I’m heading out the door in a few hours for a week-long canoe trip, so expect the next blog update around August 10. Happy long weekend!]
But are there any long term effects of all this? I think it is safe to say that after a full marathon, not many people’s brains are going to be at full capacity. We just ran 26 miles, and you expect us to remember certain dates and facts? highly unlikely. But as long as we keep our brains fit, we should be able to keep running marathons and have the same level of memory as if we didn’t run at all. It is all about keeping the brain active with puzzles and other brain challenges.
To the best of my knowledge, this is just a short-term effect — basically suggesting that running a marathon is stressful enough to put you in “fight or flight” mode, which temporarily affects brain chemistry. In the long term, exercise is supposed to be good for brain function.