Athletes and the Gut Microbiome

The following blog is a summary of key learning points from a talk given at our event ‘Digestive Health and Wellbeing: The Patient Journey’ in 2021. This blog uncovers interesting scientific research that underpins the relationship between the gut microbiome and athletes, related to performance.

Meet the speaker

Dr Neil Williams is a Senior Lecturer in Exercise Physiology and Nutrition in the Department of Sport Science at Nottingham Trent University (NTU). He established the research of exercise induced asthma and dietary supplementation at NTU, where he completed his PhD. Dr Williams currently focuses his research on the role of dietary interventions and the gut microbiota in supporting respiratory health (asthma and upper respiratory symptoms), athletic health and exercise performance.

Athletic health and the gut microbiome

The talk delivered by Dr Williams connected the dots between the gut microbiome and physical performance in terms of sports and exercise. With the continued growth of evidence for the far-reaching health benefits of the gut microbiota, interest from the Sports Medicine and Exercise Science community is not surprising. The talk presented the beneficial effect that exercise has upon the gut microbiota, which could in turn be a factor for the positive health benefits of exercise.

Summary points

Evidence of interaction between the gut microbiota and cardiorespiratory fitness is of interest in elite athletic health. The level and type of exercise that elite athletes undertake means potentially higher microbial diversity in the gut than recreational athletes, as well as sedentary individuals.

Linking sports with gut health

The need to maintain physical health in athletes is paramount to success; for athletes to perform at their best, they need to have optimal health. Demonstrating the connection between intense exercise and the gut microbiome, athletes from different sports can be distinguished by the composition of their gut microbiome (O’Donavan et al., 2020). For example, relative abundance of Veillonella, a beneficial bacterium in the gut, is related to marathon running. The increase observed is not associated directly with performance, but exercise seems to trigger a greater abundance in this strain (Scheiman et al., 2019). Studies find that Veillonella may help with processing lactate during exercise, reducing the build-up of lactic acid that can cause fatigue during periods of intense exercise.

The gut microbiota, comprising trillions of bacteria in ever-shifting compositions, is implicated in areas that are pivotal to elite sport. These important areas include immunity, energy provision and defense against gastrointestinal infections. Therefore, athletes and health practitioners need to understand that sports nutrition practices are not only fueling the athlete, but also the gut microbiome.

Athletics, immunity and the gut microbiome

Athletes with high training loads are often more susceptible to having a virus or infection than the general population, reported during times that athletes have a competition or intense period of training. Probiotics, live bacteria delivered in supplement form, could be potentially used to help to dissipate such periods of sickness in athletes. Evidence suggests that daily probiotic supplementation could lead to less disruption to health, which can in turn influence activity and performance in athletes (King et al., 2014). Furthermore, athletes taking a probiotic have been found to be less affected by respiratory infections, potentially backed up by improved immune tolerance (Pyne et al., 2015).

Multi-strain probiotics, with a viable number of cells per species to survive the body’s digestive process and reach the gut intact, may be recommended for athletes with supplementation taken at least 14 days before overseas travel or competition. Gastrointestinal symptoms associated with exercise can be affected by dietary factors - 86% of high-level athletes suffer with gastrointestinal (GI) symptoms associated with training or competitions. In answer, multistrain probiotics could be used to manage the occurrence of such symptoms (Pugh et al., 2019). Furthermore, asthma and exercise-induced asthma are common in athletes. Under test conditions, supplementation with prebiotic supplement Bimuno® resulted in an improvement in functionality of the lungs, where narrowing of airways can be associated with exercise-induced asthma (Williams et al., 2016).

The links between athletic health and gut health are still relatively new, with much more to uncover. However, as the body of evidence grows, there becomes more apparent potential for unlocking the performance-enhancing activity of the gut microbiome.