Athletes Microbiome

Studies are showing that exercise induces compositional and functional changes in the gut microbiota.1 These changes are often reversed once exercise training ceases.1 Interestingly, these differences in the gut microbiome of athletes and more sedentary individuals were previously considered to be due to differences in their diets, however, it now appears that exercise itself causes changes to the gut microbiome independent of the diet of an athlete.

Exercise is an important environmental factor that positively affects the gut microbiome, however excessive exercise has also shown to lead to dysbiosis. Individuals undertaking prolonged intense exercise may be more susceptible to illness due to exercise-induced immunosuppression.

Therefore, whilst athletes appear to have a healthier gut microbiome than the non-athletic population, those athletes which undertake the extreme physical activity with associated dietary adaptations may negatively affect their gut microbiome.

One of our nutritional experts, Claire Barnes, shares six recommendations an athlete can do to improve their microbiome for performance:



Increase antioxidants in the diet. Free radical production is high in athletes as a by-product to energy production and can cause damage throughout the body. High antioxidants foods such as blueberries, blackberries, pecans and herbs, such as turmeric and ginger, can reduce the damaging effects of these free radicals.


Eat diverse plant fibers to feed a variety of gut microbes and encourage diversity in the gut microbiome. Soluble fibers such as oats, slightly green bananas, onions, and garlic are particularly good prebiotic foods.


Avoid excessive exercise known to increase dysbiosis in the gut. Instead aim to vary your exercises and only exercise moderately allowing your body and microbiome to rest and recuperate.


Include relaxation and stretching in your exercise regime. Relaxing your mind and body is just as important for your overall health. The microbiome sends signals to the brain from the gut and vice versa. Studies have shown that dysbiosis is evident in many who suffer from stress, anxiety, and depression.


Include fermented foods in the diet to increase the diversity of the gut microbiome. Ideally make your own sauerkraut, yogurts, and kefir to ensure a long fermentation and potentially more bacterial strains. Additionally taking a multi-strain live bacteria supplement is a convenient way of increasing the number and diversity of an athlete’s microbiome.


Practice good sleep hygiene. Turn off all electronic devices ideally an hour before sleep, aim to go to bed at the same time each night, and wake up at the same time in the morning. Avoid exercising and eating late in the evenings.


1. ALLEN JM, MAILING LJ, NIEMIRO GM, et al. Exercise Alters Gut Microbiota Composition and Function in Lean and Obese Humans. Med Sci Sport Exerc 2018; 50: 747–57.

2. Barton W, Penney NC, Cronin O, et al. The microbiome of professional athletes differs from that of more sedentary subjects in composition and particularly at the functional metabolic level. Gut 2018; 67: 625–33.