We’ve all heard of the runner’s high. It comes from the endorphins produced during prolonged exercise, and it’s based on the theory that these chemicals interact with receptors in our brain to reduce pain perception, and that they may also give you a very pleasant euphoric feeling.
But a new study published in the Proceedings of the National Academy of Sciences refutes that theory, and poses a different one: that high is caused by a different substance called endocannabinoids.
The Body’s Self-Produced Marijuana
Endocannabinoids are considered the body’s self-produced marijuana, and, like cannabis, it can impact a series of physiological processes like appetite, pain, memory and mood. The research was only done in mice so how it could apply to humans is vague, but the research is compelling enough to bring forth follow-up studies. A team from the Central Institute of Mental Health of the University of Heidelberg put a number of mice in running wheels, and after a running routine, it was found that they were less anxious and more tolerant to pain.
Later on, they used drugs to block endocannabinoids in the test subjects, and the results were shocking: the animals were as anxious after their run as before, and they were more sensitive to pain. The team reports that it was ultimately brought to their knowledge that cannabinoid receptors were crucial for the main aspects of the runner’s high.
So there is indeed a connection marijuana high and a runner’s high, they might even mirror one another.
The Runner’s High Has Inspired Many Other Studies
There’s been many other interesting studies made on the subject of the runner’s high, especially in recent times. This August, a team of scientists at the University of Montreal published data on a different animal study involving leptin, a hormone nicknamed the ‘satiety hormone’, which regulates energy stores and signals to the body when it has enough fuel and energy. Researchers concluded that it’s possible that when in the middle of a workout, one’s leptin levels fall, which could send a hunger signal to the brain’s pleasure signal in order to generate the rewarding effects of running.
A different study published in the journal Cell Metabolism compared normal mice to genetically engineered mice that lacked STAT3, a leptin-sensitive protein that relays the leptin signal to release dopamine. The normal mice ran an average of 6 km per day, while the genetically engineered mice rain nearly twice the amount each day.
It Starts With Mice But it Could One Day Come in A Pill
If these studies were to progress onto human subjects, there are some that question if these effects could be put in bottles for people to exercise more and get more health benefits, and it seems to be only a matter of time.
