So Dr Fuss and his crew developed a similar experiment, but this time, with 63 human runners. And a mouse may act less anxious after exercise, but you can't ask it if it felt a euphoric buzz during its bout on the wheel. It was compelling evidence that endocannabinoids were behind the feel-good effects of running, not endorphins.īut, of course, mice aren't people. "But when we gave the mice endocannabinoid receptor blockers, all the positive effects vanished," Dr Fuss says. When the mice were given drugs that stop endorphins from latching onto opioid receptors , they still got those good post-run effects.
#IS ADRENALINE AN ENDORPHIN FREE#
They found mice that were free to scamper on a running wheel for a couple of hours were less anxious and felt less pain than their wheel-less counterparts. He and his colleagues started with animals. Johannes Fuss, a psychiatrist who now heads up the Human Behaviour Laboratory at the University of Hamburg, started investigating endocannabinoids as a potential source of the runner's high during his PhD studies. Its name is derived from the Sanskrit word ananda, which means bliss or joy. The first endocannabinoid, which was discovered in 1992, is called anandamide.The endocannabinoid system is involved in regulating appetite, pain and stress.Endocannabinoids are a group of molecules that activate cannabinoid receptors, which are found throughout the body and mainly in the brain.The main psychoactive compound in marijuana, delta-9-tetrahydrocannabinol or THC, is a cannabinoid.Īnd there's growing evidence that the high some runners experience is driven by the same system that's activated during marijuana use. In recent years, research has put forward a different class of self-made drugs: endogenous cannabinoids, or endocannabinoids. "So while they might be important, endorphins are not the only thing contributing," Dr Jones says. If you give a runner a drug that stops endorphins from doing their thing, they can still get a runner's high. "But whether or not that actually relates to someone then having those feelings of euphoria and less pain is less clear," Dr Jones says. This triggers a cascade of molecular activity that ultimately elicits feelings of wellbeing and pain relief. Like a key in a lock, endorphins slot into opioid receptors on the surface of brain cells. On the face of it, the endorphin high makes sense.
This coincides with a rise in endorphins in their blood. How long that rush takes to appear varies between people, but it typically comes on after around half an hour of running at moderate intensity, says Matthew Jones, an exercise physiologist at UNSW.
They're produced in the brain and spinal cord, and are also made and churned out into the bloodstream by the pituitary gland.Endorphins are a group of chemicals made in the body when we're stressed or in pain (the word is short for endogenous morphine).I call it "happy exhaustion": my muscles feel tired and heavy, but in a good way, and I can look forward to an afternoon of snacking and napping on the couch. Most people ( but not all) feel pretty great after a workout too. Studies have shown, time and again, exercise's long-term mental health benefits. Neuroscience is starting to untangle which naturally produced chemicals might contribute to the euphoric runner's high.