A study led by researchers at the University of Pennsylvania Perelman School of Medicine has found that some species of gut-dwelling bacteria activate nerves in the gut to promote the desire to exercise. The research found that differences in running performance within a large group of lab mice were largely attributable to the presence of certain gut bacterial species in the higher-performing animals. The team then traced this effect to bacterially produced metabolites activating sensory nerves in the gut to stimulate a motivation-controlling brain region, which then promotes the desire to exercise.
