Sports and microbiota: a virtuous circle?

Participating in high-level sports enriches the intestinal microbiota, which, in turn, may influence athletic performance.

What is a “healthy” microbiota and how can physical activity influence its composition? To find out, researchers carried out a study on 33 cyclists (22 professionals and 11 amateurs), who train between 20 and 30 hours a week at a minimum. The cyclists were divided into three groups according to the bacterial composition of their intestinal microbiota: the first group was characterized by the predominance of the genus Prevotella and a low proportion of Bacteroides; the second by the relative abundance of Bacteroides and the absence of Prevotella; and the last by a balance between five bacterial groups. The proportion of Prevotella was directly linked to training volume, becoming really significant beyond 11 hours of cycling per week. This bacterial genus, usually scarce in Europeans and Americans, turns out to be particularly favorable to athletes: it contributes to the synthesis of components that reduce fatigue and lessen muscle damage related to intense activity. The professional cyclists differed from the others with the abundance of another bacteria, Methanobrevibacter smithii, whose presence in the microbiota makes it more effective in terms of energetic metabolism. In theory, it could reduce recovery time and therefore improve performance, the researchers speculate. Their work raises other burning questions about the way these microorganisms, Prevotella and M. smithii, react to training and influence athletic performance. Does an average cyclist have more of a chance of becoming an athlete if he has M. smithii, or is it a lifestyle packed with intensive training that creates a favorable environment for the bacteria?

Petersen et al. Community characteristics of the gut microbiomes of competitive cyclists. Microbiome (2017) 5:98.