Numerous studies have reported differences between the gut microbiomes of athletes and non-athletes, with health-associated bacteria often being positively associated with physical activity.

Specific pro-/pre-biotics have been shown to positively affect a variety of performance metrics in both animal models and humans, although the mechanisms are still poorly understood.

Athletes can suffer from gastrointestinal and respiratory infections as a consequence of intense exercise. Multiple studies have shown that the microbiome composition may play a role in the gastrointestinal and respiratory infections that athletes suffer as a consequence of intense exercise.