Germany – The sudden feeling of euphoria in runners known as the “runners high” is now being related to the increase of endocannabinoids, producing a similar effect to the high people experience after consuming marijuana, according to a recent German study.

The state of general well-being experienced after exercising is known to be triggered by endorphins production, but now researchers from University of Heidelberg, University Medical Center Hamburg-Eppendorf, Gutenberg University and Max Planck Institute of Psychiatry notice these are too large to pass the blood-brain barrier and that the endocannabinoid system is also responsible for triggering the “runners high”.

Reigning world champion Mariya Savinova passed Pamela Jelimo at the top of the final straightaway and proceeded to a decisive 800-meter triumph in 1:56.19 in London 2012. Credits: Runners World

According to the Washington Post, endocannabinoids can basically be thought of as the body’s self-produced marijuana. It impacts on a wide range of physiological processes like appetite, pain, memory or mood.

To prove the involvements of endocannabinoids, the group worked with a number of mice forced to perform on running wheels regularly. One group of mice would run for five hours and the other group would remain sedentary. Results showed that running mice displayed far less anxious behaviorand a higher tolerance for pain than the sedentary ones (measured by their tendency to jump or lick their paws when placed on a hot plate.)

Then the group of running mice was given drugs to block endorphins and endocannabinoids while exercising that resulted in their anxiety and sensitivity to pain reduced to usual levels but no longer joy for running during long periods. Even though the research was only in mice, the team’s findings suggest that endocannabinoids help cause runner’s high. For now it is unclear how the study will apply for humans.

“The authors have moved the field forward by providing such a complete view of how this key reward system is involved in allowing exercise to improve psychological state and pain sensitivity,” sayd David A. Raichlen, an expert in human brain evolution and exercise at the University of Arizona.

Source: The Washington Post