In line with what I’ve been saying for years now, today The Well has a report of new research supporting the hypothesis that endocannabinoids are much more likely to be the source of runner’s high than endorphins. (See my endocannabinoids tag for previous posts.)
The gist of the experiment was to give mice running wheels, and then measure both mood (anxiety levels, as shown by a willingness to linger in light areas, as opposed to staying in the dark) and blood levels of endocannabinoids and endorphins. Then they used drugs to selectively block receptors for cannabinoids. Doing so eliminated any observable anxiety-reduction effects from running. Blocking receptors for endorphins had no such effect.
The study itself: A runner’s high depends on cannabinoid receptors in mice.
In keeping with earlier research on this effect, the amount of running it takes to see a strong endocannabinoid effect was substantial—the mice were running more than 3 miles a day. I don’t know how far three mouse miles is in human miles. Earlier research suggested that 50 minutes of running was sufficient in humans.
So the subtle upshot of the new study may be that we should run. And if we don’t feel a high, perhaps try running more, until eventually a gentle euphoria may settle in and we can turn to our running companion and say, “Ah, my endocannabinoids are kicking in at last!”
I should probably find some running companions to share this with. I almost always run alone, and it seems like my endocannabinoids kick in just about exactly when I no longer feel any urge to wonder about whether they’re going to kick in or not.
Here’s one of the paths through the prairie where I run:
