Could your gut hold the key to running motivation?

Why do some people seem to be more motivated than others to exercise? How can you increase your motivation to go out for a run or push harder in workouts? New research suggests that the answer may be found in your gut. According to researchers at the Perelman School of Medicine at the University of Pennsylvania, some species of gut-dwelling bacteria can increase your motivation to exercise.

The gut-brain connection

There has been a lot of research in the last decade dedicated to the connection between your gut and your brain, and it is now generally understood that your gut (specifically the billions of bacteria that live in your gut and intestines) has a profound impact on your mood, and even your behavior.

This new study, published in the scientific journal Nature, discovered that certain bacteria in the guts of lab mice had a substantial impact on their running performance. The reason, according to the study’s authors, can be attributed to the metabolites produced by these bacteria.

The study

The researchers set up the study to test for multiple factors that may influence running performance. Using a set of genetically diverse mice, they recorded their genome sequences, gut bacterial species, bloodstream metabolites and other data. To conduct the study, they simply measured how much voluntary wheel running the mice did every day, as well as how long they ran each time (to measure their endurance). 

There was a significant difference in the amount of wheel running, as well as endurance, across the groups of mice, and the researchers used machine learning to measure which factors seemed to have the most influence on this difference. 

The results

All bacteria in your body, including your gut, produce metabolites, which stimulate different nerves in your body. The researchers in this study discovered that the metabolites produced by certain gut bacteria stimulated sensory nerves in the gut that enhance activity in the region of the brain that is responsible for motivation during exercise. 

The two main gut bacteria that had the greatest impact were eubacterium rectale and Coprococcus eutactus. These bacteria produced fatty acid amides (FFAs), which stimulated specific receptors in the gut called CB1 endocannabinoid receptors, which connect to the brain by way of the spine. When you stimulate these receptors, it increases the amount of dopamine in your brain, which increases your motivation to exercise.

In other words, mice that had more of these bacteria did a much higher volume of voluntary running and ran for much longer than mice that had less. They also found that if they gave the mice a broad-spectrum antibiotic, which reduced the number of bacteria in their guts, their running performance was reduced by 50 per cent. Interestingly, genetics only seemed to account for a very small amount of performance differences.

The takeaways

This research, which took place over a number of years, has only been done in mice, but it could have significant implications for humans. “If we can confirm the presence of a similar pathway in humans, it could offer an effective way to boost people’s levels of exercise to improve public health generally,” said study senior author Christoph Thaiss.

The team is now planning to do further research to confirm the presence of this pathway in humans, which could open the door for an entirely new branch of exercise psychology research. In the meantime, this is yet another reminder of the importance of having a healthy gut microbiome, so if you’re struggling with motivation to get out the door, maybe the answer is in your gut?

posted Tuesday July 25th
by Brittany Hambleton