Boost Your Gut Health, Boost Your Performance

Gut health is getting a lot of attention these days and for good reason. There are roughly 10 times more bacteria than cells in your body and an estimated 400 different types of bacteria in the intestinal tract alone, which work closely with your enteric nervous system to signal hunger, mood, illness and other internal cues. This concentration of bacteria in the gut is a large reason many health professionals believe in the gut-brain health connection, and that a larger, more diverse and balanced microbiome equals a healthier body.

Often referred to as the ‘second brain,’ the gut, or microbiome, is involved in many bodily functions and has been closely linked to health. Everything from mood to immunity to digestion, disease prevention and, more recently, athletic performance.

While most people share a core makeup of microorganism species, the amounts of each vary greatly person to person. This individual makeup is influenced by genetics, environment, stress, lifestyle habits, age, fat tissue, exercise, disease conditions and food intake. It is this unique gut biome makeup that can affect health outcomes and why working to promote a healthy gut is so important.

Probiotics are beneficial bacteria that inhabit your gut and support healthful life functions such as food digestion, the absorption of nutrients and healthier skin.

What throws this healthy balance off is poor lifestyle factors and bad diet choices, which kill off the healthy bacteria and result in a sluggish body and potential poor health outcomes. Probiotics have been studied extensively in the digestive process, but also have been linked to just about every other health indicator, including diabetes, immunity and weight. In fact it has been shown that obese individuals have a different gut biome than lean individuals and fecal transplants from lean animals can make obese animals lose weight.

There’s no denying probiotics play an important part in health, but there’s also no concrete evidence that supplementing with the little bugs helps at all. This is largely because each person has such an individual gut microbiome, and finding the right strands of probiotics in the right amounts and active forms for your specific body is very difficult. Research has shown one strain of bacteria might help immunity in some, while another strand has no effect at all. This might indicate each strand has unique benefits or that there are only benefits from a strand the athlete needs. The best way to boost your biome is to eat a diet loaded in naturally probiotic-rich foods such as sauerkraut, kefir, tempeh, aged cheeses, miso and kimchi.

Consuming probiotics, even through natural food sources, isn’t enough to reap the full benefits. These bugs need to eat, and it is your job to feed them with their nutrition of choice: prebiotics. Prebiotics are nondigestible food substances that enhance the effects of probiotics by helping them thrive and stay active. Foods such as bananas, chia seeds, wheat, onions, chicory and artichokes are all sources of prebiotics.

OK, so these gut bugs, whether supplemented or through whole-food intake, are good for health, but their impact on performance is much less clear. There is very little research to support the notion that probiotics will directly lead to a personal record or spot on the podium. However, they are linked to improved general health, which is the foundation of being a good athlete. You can’t outrun (or ride or train) a bad diet or poor health, so focusing on foods that improve overall gut health will likely, although indirectly, turn you into a better athlete.

Engaging in regular physical activity creates positive biome changes. In rodent studies, voluntary exercise improved prevalence of disease protective bacteria strains. Mice fed a high-fat, obesity-inducing diet who also were subjected to exercise saw a conversion of gut biome makeup resembling lean mice, indicating exercise can combat a poor diet.

Research on humans found similar results — higher cardiovascular fitness was connected to a significant increase in gut diversity. This is very important, as a lack of bacterial strain diversity correlates with poor health outcomes. Voluntary exercise needs to be part of a long-term lifestyle as exercise-induced gut adaptations revert after a period of sedentary behavior. While more diverse and long-term research is needed, the information available thus far points to regular exercise being beneficial for the gut, and a healthy gut is undoubtedly linked to a healthy mind and body.

For those looking for a competitive edge, improving gut health might be the answer. Gut biomes of runners at the 2015 Boston Marathon were observed and found to have a significant increase in performance-enhancing bacteria compared with sedentary individuals.

Veillonella is a bacterium that can metabolize lactate for energy. Lactate buildup is responsible for diminished performance, muscular pain and fatigue. Mice injected with this strain of bacteria could run 13% faster on a treadmill test compared to those without the additional Veillonella.

Professional cyclist’s guts also contain more performance-benefiting bugs than amateur riders. Prevotella bacteria increased in the professional cyclist’s gut biome contributes to metabolic processing of amino acids and carbohydrates, potentially allowing the athletes to better utilize fuel sources for performance energy. Promising results for how the gut biome’s diversity and individual bacterial strains can work to boost athletic outcomes and how altering that biome could be the next supplemental way to achieve athletic success.

Here are four areas probiotics could make the biggest impact on performance:

• Digestion: High-impact sports like running put stress on the gastric system This combined with the intake of processed simple sugars puts athletes at risk for suffering from gastric distress, including bloating and irritation. Research is convincing that probiotics assist with easing digestion, increasing nutrient absorption and improving gastric distress. In a trial of trained cyclists, symptoms of leaky gut were decreased after 14 weeks of multi-strain probiotic supplementation.

• Immunity: Athletes are at higher risk of upper respiratory infections than the general public, as the immune system becomes depressed during heavy training. No athlete wants to get sick and have to sit out vital training sessions or possibly miss competitions. Several studies point to a link between increasing probiotics and reduced incidence of respiratory illness. One such report came from a study of 20 elite runners given lactobacillus fermentum supplements who cut the number of days symptoms of illness in half and the severity of symptoms experienced were lessened. A review of probiotics and performance concluded no significant results, except noting indications of improved immune response in fatigued athletes.

• Overtraining: This is an immune-related response athletes are at risk of experiencing when training stresses (physical and mental) build up without proper recovery and become more than the athlete can tolerate. One study found markers of depressed immunity in overly fatigued athletes can be reversed with probiotics.

• Weight: Athletes strive for a lean body to improve their power-to-weight ratio and range of motion and to meet weight-dependant sport requirements. Eating foods rich in pre- and probiotics also helps create a sensation of satiety while being nutrient-rich and generally lower in calories.

For those looking to have good health and performance, enhancing the gut biome should be on your to-do list. In addition to regular physical activity, there are many dietary steps one can take to improve the gut microbiome. Many probiotic supplements claim to boost internal probiotic content, but there is limited evidence that consuming supplements is useful. Instead, opt for whole foods that naturally stimulate a diverse bacterial environment; consume naturally fermented foods such as yogurt, kimchi, kombucha, pickles, miso, tempeh and sourdough.

Probiotic foods alone are not enough to stimulate growth of these good bugs; they need to be fed prebiotics from sources such as chicory, garlic, asparagus and bananas. Limiting highly refined, processed foods and artificial ingredients will limit gastric inflammation, making a nice environment for your bacteria to flourish in. The hopes of improved performance should be a great motivator to make dietary improvements.

Originally published October 2019, updated with additional reporting.

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