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Gut Health

Can Your Microbiome Impact Your Performance?

Learn about the gut bacteria elite athletes share, and how to build your own performance-enhancing microbiome.

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It’s hard to believe that before the late 1990s, health experts did not generally recognize the microbiome even existed, let alone have a profound influence on human health. But now, registered dietitian Aja Gyimah, says the gastrointestinal microbiome, the community of microbes that live inside of us, is linked with a host of other health conditions. “The gut microbiome has been shown to play a role in several bodily functions such as digesting food, influencing our immune systems, and even produces some vitamins like vitamin K. It has also been shown to influence neuroscience, our mental health and autoimmune diseases.”

And, according to a recent collaborative study between the Wyss Institute, Harvard Medical School and the Joslin Diabetes Center in Boston, the microbiome may even enhance athletic performance. 

Performance-enhancing bacteria

In this study, researchers discovered an abundance of the bacteria group Veillonella in the gut microbiomes of Boston Marathon runners post-race, and also elite Olympic athletes right after competing. When these same scientists gave Veillonella to laboratory mice, the animals increased their treadmill time performance by an average of 13 percent, compared to a control group. While more analysis is needed, researchers observed Veillonella microbes broke down the abundance of lactate (also called lactic acid buildup) produced by exercise and converted it to the short chain fatty acid called propionate. Further investigation led these researchers to believe these specific bacteria enhanced athlete performance by creating propionate. 

How your microbiome can improve performance – even without Veillonella

Can hobby athletes and regular exercisers alike run out and buy Veillonella probiotics? Not yet. But that’s not to say we can’t stack the odds of building a microbiome that helps us perform our best. 

A former elite athlete herself before starting the sports nutrition practice Compete Nutrition, Gyimah says helping her clients maintain a healthy microbiome is an important element to their overall performance. She explains the intensity of an athletic training schedule can influence digestion and suppress the immune system. That means, taking care of their gut microbiome can help athletes build resilience plus help avoid digestive upset and illness. Even general stress and anxiety may reduce the biodiversity of the microbiome, as evidenced in another recent study, an added reason to keep existing colonies well fed and happy. 

“Plenty of fiber and fermented foods that contain probiotics, which are live strains of bacteria, are things that I commonly recommend to my clients to keep their gut healthy,” explains Gyimah. But because most people usually think of proteins, carbs and fats when it comes to fitness nutrition, she says feeding beneficial gut bacteria with dietary fiber is just not on her clients’ radar. “When I mention the relationship between these foods and the gut microbiome, I usually get a few raised eyebrows.” 

But if the Veillonella discovery leads to further connections to gut bacteria and performance, maintaining the microbiome just might become the first thing athletes think of. 

How to build your own athletic microbiome

Whether you exercise to keep your body fit, or want to crush your next competition, Gyimah reiterates that dietary fiber is the key to a healthy microbiome, and by extension a more resilient body. “Fiber is not easily digested by the body so it is used in the large intestine as food for our gut bacteria. This allows our ‘good’ bacteria to flourish,” she says. For her clients, she recommends the age-old approach of eating plenty of whole grains, fruits and vegetables every day. 

Even regular exercise itself can have a positive influence on your gut bacteria. But Gyimah cautions exercising too hard without adequate fuel can negatively impact the microbiome, among other bodily functions. “Before you think about improving your gut microbiome, I would recommend looking at your entire diet first to ensure you’re eating enough.” 

Give your gut bacteria its best chance for optimal performance with a fiber-rich diet, stress management and plenty of exercise. With these strategies, maybe you’ll be able to run the Boston Marathon and develop your own Veillonella colonies, too. 

Try our Fitness-Friendly One-Week Meal Plan for a dietitian-curated menu to support your active lifestyle. Or read Fuel Your Fitness Routine for supplements to consider for better performance.