Getting to the bottom of the runner's high 16 Mar, 2021 01:02 AM 5 minutes to read Runners develop a gentle intoxication, known as a runner's high. Photo / 123RF New York Times For years we've been crediting endorphins, but it's really about the endocannabinoids. We can stop crediting endorphins, the natural opioid painkillers produced by our bodies, for the floaty euphoria we often feel during aerobic exercise, according to a nifty new study of men, women and treadmills. In the study, runners developed a gentle intoxication, known as a runner's high, even if researchers had blocked their bodies' ability to respond to endorphins, suggesting that those substances could not be behind the buzz. Instead, the study suggests, a different set of biochemicals resembling internally homegrown versions of cannabis, better known as marijuana, are likely to be responsible.