Moderate Exercise has Limited but Distinguishable Effects on the Mouse Microbiome

Background: The human microbiome is known to have a complex, yet vital relationship with human health. While both exercise and the gut microbiome have been shown to independently impact human health, the direct effects of moderate exercise on the intestinal microbiota remain unclear. In this study, we compared gut microbial diversity and changes in inflammatory markers associated with exercise in mice that completed either a voluntary (VE) or forced moderate exercise (FE) protocol and mice that did not perform any exercise protocol.Results: VE mice, but not FE mice, had increased food intake and lean body mass when compared to sedentary mice. Levels of inflammatory markers associated with exercise were similar between all three groups. Traditional microbial profiling analysis did not identify significantly altered taxonomic profiles in the voluntary or forced exercise group when compared to the sedentary controls. However, machine learning using Random Forests could accurately identify exercisers from non-exercisers and identified taxa important in this classification. Conclusions: Aerobic exercise in mice did not result in a large impact on the gut microbiome or in host inflammatory response, although more sophisticated computational methods could identify some microbial shifts. More study is needed on the effects of various exercise intensities and their impact with the gut microbiome.