Watching the joy on Busu’s (our adorable Whippet-Jack Russel Terrier) face during this week’s run together, reminded me of this Economist article “Exercise and addiction” http://www.economist.com/node/21552536
- Running triggers the release of brain chemicals called endocannabinoids that create a potent feeling of pleasure in the same way as the active ingredient of marijuana
- The surge of endocannabinoids aka “runner’s high” is an evolutionary benefit that was used to encourage humans to remain fit enough to run after game and away from predators and enemies for survival.
- A study led by David Raichlen of the University of Arizona has revealed that the runner’s high exists in other species who gain an evolutionary benefit from being fast on their feet
- After running the average human’s endocannabinoid levels rose from 2.4 picomoles per millilitre (pmol/ml) to 6.1. Dogs showed a similar trend, with levels rising from 2.4 pmol/ml to 8.0
- Ferrets did not show a statistically significant rise because running consumes a lot of energy, may cause injury, and is not crucial to the stealthy hunting technique of sneaking down burrows and killing rabbits in their sleep