That feel-good and relaxed sensation we call runner’s high is closer to the effects of marijuana than most might think, as researchers suggest endorphins got undeserved credit for that wave of euphoria.
- After running, our bodies naturally produce both endorphins and endocannabinoids
- Researchers believed that endorphins are much too large to pass through the brain’s blood barrier
- Experiments were conducted on mice, and the effect of each compound was artificially cancelled out
- When they dulled out the effect of endocannabinoids, the runner’s high in mice disappeared
Any long runner could attest to the feeling of calm and utter relaxation after a successful and tiring run. They gain an unnatural amount of energy and ‘happy feeling’. This is in spite of the dreaded and physically taxing exercise that essentially works out every single muscle. Until now, a strong release of endorphins was given all the credit.
Endorphins are considered to be our body’s natural painkillers, and provide us with that boost of energy and feeling of happiness after intense physical activity. Researchers in the 80s conducted experiments that observed huge spikes of the compound after exercise in humans. That led to the natural, simple and logical explanations that they were responsible for runner’s high.
However, it has been suggested that endorphins are a much too large type of molecule to fit through the brain’s blood barrier. This has made researchers believe that they cannot possibly be the cause of runner’s high, if they cannot slip through and attach to the brain’s receptors. So, they spent the last 10 years looking into other potential explanations.
Researchers at the Central Institute of Mental Health at the University of Heidelberg have found other compounds that might lead to runner’s high: endocannabinoids. After a long, intense run, the body produces both beta-endorphin (known as an opioid) and anandamide (known as an endocannabinoid), according to the scientists. Only one of them is small enough to cling on to the brain’s receptors. A hint, it’s not endorphin.
Endocannabinoids are produced naturally in our bodies, but it’s also one of the containing molecules in cannabis, or marijuana. Recent studies have found a spike in their numbers after extensive training sessions and intense exercise, so they took the study a step forward. The researchers experimented on mice, setting them on a wheel, and simply watched them.
They suggest that the rodents could feel something akin to runner’s high, which is why they find it fun to run in place. It’s unlikely they care about their health or want to slim down. In mice, the calm and decreased anxiousness expresses through their behavior. After a run, mice are much more likely to spend time in well-lit parts of their containment. Nervous rodents just sit in the dark.
While there was a spike in both endorphins and endocannabinoids, researchers artificially cancelled out the effects of each in part. When they blocked the effects of endorphins, nothing different happened. However, after cancelling out endocannabinoids, the runner’s high disappeared entirely, and the rodents were no longer calm and relaxed.
This has led them to the conclusion that endorphins might have been given far too much credit to the ‘after buzz’ following a good, long run. While authors of the study mentioned that there’s no guarantee the same thing happens in mice as it does in humans, there’s a strong possibility it does.
The mice did run 3 miles per day though, so this might not be for amateurs. It does ring differently that runner’s high is very similar to a different kind of high.
Image source: yptparis.com