Runners’ High: Why Dogs Make Better Exercise Partners than Ferrets

People who love exercise often refer to a feeling of euphoria or invincibility that washes over them during good exercise. Some experience the feeling fairly regularly, while others refer to an exceptional experience that happens only occasionally

Higher endorphin levels that have been measured in the blood during strenuous exercise
The effects of rising core body temperature on the brain
Increased levels of anandamide and other endocannabinoids in the blood during strenuous exercise. Anandamide stimulates the same brain receptors as THC in cannabis.

It also turns out that this effect may not be unique to humans. Some mammals routinely engage in high-intensity endurance activities, while others do not. Researchers have long speculated that runner’s high is there to increase endurance activity in humans. Anthropologist David Raichlen hypothesized that if chemical indicators of runners’ high correlated with endurance activities across different animals, this would support the theory that runners’ high makes us run.

More than hypothesize, he and his research colleagues put humans, dogs, and ferrets on treadmills and then took blood samples. As expected, both humans and dogs had increased levels of endocannabinoids after high-intensity endurance exercise, but not after walking. The ferrets, on the other hand, did not have an increase in endocannabinoids regardless of the exercise type. The researchers propose that the running and playing behavior we observe in both dogs and humans may be chemically programmed behavior, and that animals not built for running won’t have the same biochemical rewards.

Your dog will enjoy a good run or brisk walk, and your body will thank you.

Reference:

Raichlen D, Foster A, Gerdman G, et al. Wired to run: exercise-induced endocannabinoid signaling in humans and cursorial mammals with implications for the ‘runner’s high’. The Journal of Experimental Biology. 2012 April 15; 215: 1331-1335.