According to a new study published in Psychoneuroendocrinology, endorphins are not responsible for “runner’s high,” the euphoric state that some runners report experiencing during lengthy exercise. For decades, scientists assumed that endorphins, an endogenously-produced opioid, were behind the somewhat-mythical state, but the latest research actually credits endocannabinoids.
Yes, you read that last bit correctly. A naturally-occurring compound that’s biochemically similar to marijuana is lighting up our pleasure sectors during running — and these fun endocannabinoids also make an appearance in the brain during orgasms.
In order to reach this conclusion, researchers recruited over 60 different experienced runners and randomly administered a drug that blocks the flow of endorphins. After a 45-minute run, during which most of the volunteers experienced a runner’s high to some degree, the scientists measured the euphoria and anxiety of each runner. Even with endorphins inhibited, people were content and relaxed. The endocannabinoids had gone to work, positively impacting the runners’ emotional states.
Unlike endorphins, endocannabinoids are able to make the leap from the bloodstream to the brain. The inability of endorphins to do the same is why scientists started doubting their involvement in the runner’s high in the first place. If you ever needed more reason to get outside and exercise, well, here you are. This is peer-reviewed, double-blind research in support of getting biochemically buzzed while out on your next jog.
As for why our bodies do this? It’s likely a relic from our hunter-gatherer days. If you’re chasing a gazelle across a savanna for an hour or more, it helps to remain in good spirits.