The effect of exercise and diet on gut microbial diversity

We have read with great interest the study by Clarke et al 1 who in a very elegant and sophisticated manner documented the increase in gut microbial diversity in association with exercise and dietary extremes in professional rugby players. The observed microbial shifts were accompanied by lower inflammatory and healthier metabolic profiles among athletes. Significantly higher proportions of the genus Akkermansia muciniphila in athletes as well as in low Body Mass Index control group were found. As previously shown, the presence of these bacteria in the human GI tract has been associated with improved metabolic profiles, possibly due to enhanced barrier function. However, from the study of Clarke et al it is difficult to draw the conclusion and assess the impact of exercise per se from dietary influences in groups studied for their gut microbial diversity. As the alterations of the microbial diversity have already been linked to changes in dietary habits, …