Research Paper Title

Exercise Alters Gut Microbiota Composition and Function in Lean and Obese Humans.

Background

Exercise is associated with altered gut microbial composition, but studies have not investigated whether the gut microbiota and associated metabolites are modulated by exercise training in humans. The researchers explored the impact of 6 weeks of endurance exercise on the composition, functional capacity, and metabolic output of the gut microbiota in lean and obese adults with multiple-day dietary controls before outcome variable collection.

Methods

Thirty-two lean (n = 18 [9 female]) and obese (n = 14 [11 female]), previously sedentary subjects participated in 6 wk of supervised, endurance-based exercise training (3 d·wk−1) that progressed from 30 to 60 min·d−1 and from moderate (60% of HR reserve) to vigorous intensity (75% HR reserve). Subsequently, participants returned to a sedentary lifestyle activity for a 6-wk washout period. Fecal samples were collected before and after 6 wk of exercise, as well as after the sedentary washout period, with 3-d dietary controls in place before each collection.

Results

β-diversity analysis revealed that exercise-induced alterations of the gut microbiota were dependent on obesity status. Exercise increased fecal concentrations of short-chain fatty acids in lean, but not obese, participants. Exercise-induced shifts in metabolic output of the microbiota paralleled changes in bacterial genes and taxa capable of short-chain fatty acid production. Lastly, exercise-induced changes in the microbiota were largely reversed once exercise training ceased.

Conclusions

These findings suggest that exercise training induces compositional and functional changes in the human gut microbiota that are dependent on obesity status, independent of diet and contingent on the sustainment of exercise.

Reference

Allen, J.M>, Mailing, L.J., Niemiro, G.M., Moore, R., Cook, M.D., White, B.A., Holscher, H.D. & Woods, J.A. (2018) Exercise Alters Gut Microbiota Composition and Function in Lean and Obese Humans. Medicine and Science in Sports and Exercise. 50(4), pp.747-757. doi: 10.1249/MSS.0000000000001495.