The Diet and Exercise-Microbiome Paradigm: Distinct Functional Profiles of the Athlete Microbiome Revealed by Metagenomic and Metabolomic Analysis

The contribution of the human intestinal microbiome to host health has become increasingly apparent over the past decade. It is evident that the gut microbiota and factors that influence its composition and activity influence human metabolic, immunological, and developmental processes. Most and perhaps all elements of modern lifestyle influence the intestinal microbiota; including habitual diet and even sedentary occupation and physical conditioning. Extreme physical activity such as that pursued by elite or professional athletes and associated dietary adaptations have been correlated with changes in faecal microbial diversity and composition relative to that of controls with a sedentary lifestyle. However, it has not been established if these compositional differences are linked with variation in microbial functionality. Here, we show by functional metagenomic and metabolomic analysis, that extreme physical activity and associated dietary adaptations of professional international rugby union players is associated with functional differences in the gut microbiome. Athletes had relative increases in pathways (e.g. amino acid and antibiotic biosynthesis and carbohydrate metabolism) and metabolites (e.g. the short chain fatty acids [SCFAs] acetate, propionate, and butyrate) associated with enhanced muscle turnover (fitness) and overall heath when compared to both control groups.