Your gut can motivate you to exercise
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Your gut might be your most important organ, or at least the one that has the most influence on your life. It's all about the dopamine.
How the Gut Microbiome Can Affect Motivation to Exercise
Anthony L. Komaroff, MD, reviewing Dohnalová L et al. Nature 2022 Dec 22/29 Agirman G and Hsiao EY. Nature 2022 Dec 22/29 Pennisi E. Science 2022 Dec 16
At least in mice, gut microbes affect the brain's reward center during exercise.
When mice are given the opportunity to exercise, they (like humans) vary considerably in their enthusiasm for doing so. A team at the University of Pennsylvania found that some “active” mice will run nearly 20 miles on a wheel in a 48-hour window, whereas other “lazy” mice barely will use the wheel.
The investigators found no genetic differences that explained the very different behavior of active and lazy mice. Instead, the behavioral differences were caused by differences in the gut microbiome. Active mice had an abundance of bacterial species that produced particular types of fatty acids. These fatty acids set in motion a series of signals that led to increased dopamine in the brain's reward centers when the animals exercised. The resulting “runner's high” encouraged further exercise. When the active mice were treated with antibiotics that killed their gut microbiome, they became inactive; restoration of their original microbiome led to increased exercise. Mice raised in a germ-free environment were lazy; when lazy mice were given gut microbes from active mice, they greatly increased their exercise.
