Dynamics of gut microbiota and short-chain fatty acids during a cycling Grand Tour are related to exercise performance and modulated by dietary intake
Authors: Fernández-Sanjurjo Manuel , Fernández Javier , Martínez-Camblor Pablo , Rodríguez-Alonso Manuel , Ortolano-Ríos Raquel , Pinto-Hernández Paola , Castilla-Silgado Juan , Coto-Vilcapoma Almudena , Ruiz Lorena , Villar-Granja Claudio J , Tomás-Zapico Cristina , Margolles Abelardo , Fernández-García Benjamín , Iglesias-Gutiérrez Eduardo , Lombó Felipe 
Published: December 2022

ABSTRACTObjectiveThe aim of this study was to analyse the dynamics of faecal microbiota composition and short-chain fatty acids (SCFAs) content of professional cyclists over a Grand Tour, and their relationship with performance and dietary intake.Design16 professional cyclists competing in La Vuelta 2019 were recruited. Faecal samples were collected at four time points: The day before the first stage (A); After 9 stages (B); After 15 stages (C); On the last stage (D). Faecal microbiota populations and SCFAs content were analysed using 16S rRNA sequencing and gas chromatography, respectively.ResultsA principal component analysis (PCA) followed by Generalized Estimating Equation (GEE) models were carried out to explore the dynamics of microbiota and SCFAs, and its relationship with performance.Bifidobacteriaceae, Coriobacteriaceae, Erysipelotrichaceae, andSutterellaceaedynamics showed a strong final performance predictive value (R2=0.83, ranking and R2=0.81, accumulated time). Positive correlations were observed betweenCoriobacteriaceaeand acetate and isovalerate andBifidobacteriaceaeand isobutyrate. No relationship was observed between SCFAs and performance. The abundance ofBifidobacteriaceae, Coriobacteriaceae, andErysipelotrichaceaeat the beginning of La Vuelta was directly related to the previous intake of a complex-carbohydrate-rich food, potatoes, while during the competition the abundance ofBifidobacteriaceaewas negatively affected by the intake of simple carbohydrates from supplements.ConclusionAn ecological perspective represents more realistically the relationship between gut microbiota composition and performance, compared to single-taxon approaches. The composition and periodisation of diet and supplementation during a Grand Tour, particularly carbohydrates, could be designed to modulate gut microbiota composition that allow better performance.KEY MESSAGESWhat is already known on this topicGut microbiota composition and metabolic activity change in response to acute exercise and training and can directly influence physical performance. However, the effect of a cycling stage race, which entails repeated and continuous days of competition, with extreme physiological and metabolic demands, has not been analysed.What this study addsOur results show that microbiota dynamics during a Grand Tour involve many taxa and allow performance prediction. Those dynamics are related to dietary intake, both prior to and during competition.How this study might affect research, practice or policyOur results demonstrate that limiting the relationship between gut microbiota composition and sports performance to a single taxon or metabolite is a reductionist approach that does not reflect the complexity of the microbial ecosystem. It may help to optimize the composition and periodisation of diet and supplementation based on gut microbiota modulation to optimize performance.