Written by Regin Smith | Reviewed by Fit with Food Dietitians

The gut microbiome has become an increasingly popular topic in nutrition and mainstream media over the years. The gut microbiome is an important part in your overall health and well-being, and for athletes, it plays a large role in their performance. 

What is the gut microbiome? 

In order to understand how the gut microbiome plays a role in athletic performance, we need to first understand what it is. The human gut microbiome is defined as a collective genomes of  microbiota in the gut. It can be influenced by many different factors such as age, activity level, medication, and diet.1 The gut microbiome can adapt to be positively modified due to dietary interventions, the use of pre- or pro- symbiotics, or exercise.2 

The gut microbiome and athletic performance

The gut microbiomes of athletes and non-athletes have been noted to be significantly different from each other. Athletes’ gut microbiome has been found to be more diverse and has greater levels of health promoting bacteria.2 

Exercise has been found to have a dose-dependent effect on an individual’s gut health and immune function. Moderate levels of exercise have been seen to have positive effects on health. Meanwhile, extreme levels of exercise have been seen to have negative effects on the body, including increased gastrointestinal distress.2 These negative effects have mostly been seen in those who participate in extremes of exercise, such as ultra-marathon runners. In a recent study, it was found that 96% of ultra marathon runners experienced some sort of gastrointestinal distress during their 100 mile race, with 35.6% saying that this distress contributed to them not finishing their race.2 

However, it has been found that microorganism-based interventions have been found to help mitigate the negative effects of extreme exercise on one’s gut microbiota. In addition, it is thought that these interventions can also help to improve athletic performance by enhancing muscle growth and endurance.2

The production of short chain fatty acids (SCFA) is thought to be important in athletic performance due to the SCFA butyrate.2 Butyrate is one of the most important for gut health in general. It plays roles in strengthening the intestinal barrier, regulating inflammatory responses, and modulating important metabolic functions.2

There have been a number of studies done showing that gut microbiome composition and modifying treatments can positively influence endurance.2 However, further study needs to be done in order to fully understand this and the effect it can have on athletes.  

What can you do to improve your gut microbiome?

There are many things you can implement into your daily routine that can help to improve your gut microbiome.

Eat a diverse diet. Eating a variety of food can help to make sure you are getting all of the different vitamins, minerals, and nutrients your body needs. There’s a reason you’ve been told to ‘eat the rainbow’!

Consider taking a probiotic. Probiotics are the “good” bacteria found in your body that help to fight off the “bad” bacteria. By taking a probiotic, you are helping to populate your gut with this good bacteria. However, you do not need to take a supplement to do this. There are many foods that you can add to your diet that are great probiotics. This includes many fermented foods like yogurt, cottage cheese, sauerkraut, and pickles. If you feel as though you could benefit from taking a probiotic supplement, you should work with a dietitian. 

Work with a dietitian to find your individual needs and how to best meet them!

References

1. O’Brien MT, O’Sullivan O, Claesson MJ, Cotter PD. The Athlete Gut Microbiome and its Relevance to Health and Performance: A Review. Sports Med. 2022;52(Suppl 1):119-128. doi:10.1007/s40279-022-01785-x 
2. O’Brien MT, O’Sullivan O, Claesson M, Cotter P. GUT MICROBIOME FUNCTION, STABILITY AND PROFILING, AND RELEVANCE TO ATHLETES. Gatorade Sports Science Institute. Published September 2022. Accessed July 2, 2024. https://www.gssiweb.org/en/sports-science-exchange/Article/gut-microbiome-function-stability-and-profiling-and-relevance-to-athletes#articleTopic_8