When milliseconds can mean the difference between silver and gold, endurance athletes in sports like marathon running, cycling, rowing and swimming optimize every aspect of their physiology for a competitive edge.
Many of these efforts result in enhancing the , the tiny but mighty energy-generating powerhouses within your cells. Carefully calibrated combined with beneficial stress – , and – and optimized recovery in the form of , and , positively affect the number and health of in the cells of your , and .
But there is another aspect of endurance training that may have largely been overlooked by athletes and trainers – the role of the in optimizing your mitochondrial health and fitness.
I am a who has studied how food affects the gut microbiome’s role in health and disease for over 20 years. While research evaluating is improving our understanding of conditions like , , and , it might also help athletes achieve new levels of performance through innovative approaches to nutrition.
Of microbiomes and mitochondria
The gut microbiome, a hidden factory of highly collaborative microorganisms in your intestines, ensures that your metabolism, immune system and brain run smoothly. Some researchers liken it to that senses nutritional inputs, manufactures signaling molecules and prepares your body to respond appropriately.
Research has shown that endurance athletes have different gut microbiomes compared with the general population. Their and function, like increased production of a short-chain fatty acid , are associated with increased VO2 max, a fitness benchmark that measures your ability to consume oxygen during intense exercise. One organism in particular, is found in some elite runners and may help raise lactate threshold, a fitness metric closely linked to mitochondrial function and how long an athlete is able to sustain intense effort.
A healthy microbiome , the tiny structures within your cells that convert calories into the raw cellular energy required for muscle contraction and other essential functions. It does this by transforming undigested food components of a – like , and – into molecules that increase the .
Some of these metabolites – , and among them – have been shown to specifically improve muscle strength and endurance. Combining exercise with diets high in fiber, polyphenols – a chemical compound from plants – and healthy fats may thus and improve exercise performance.
Nutritional gaffes and gaps
Healthy diets are critical for microbiome and mitochondrial health. Conversely, ultra-processed diets have been linked to conditions ranging from and to and . Some people believe athletes are protected from the due to the . While this may partially be true, it’s important to consider other factors in diet beyond just the calories burned.
used to improve the taste and appearance of food, , can negatively affect the gut microbiome, compromising the and causing , an unhealthy state linked to , , and . Ultra-processed foods have also like fiber, polyphenols and healthy fats found in whole foods that support gut health and signal to the mitochondria that there are calories to be metabolized.
The drinks, shakes, bars and gels used for endurance sports are formulated to provide concentrated and accessible energy during intense exercise. While unhealthy in other contexts, they can be key for during long endurance events when your body depletes its own version of accessible carbohydrates called glycogen.
But it’s important to complement these energy supplements with a healthy diet in the recovery hours following exercise. The combination of an unhealthy baseline diet with high-intensity exercise could compromise your gut barrier and increase inflammation. This has been linked to various training-related issues including , and .
Performance-enhancing microbes
Reintroducing a diet rich in – beans, nuts, seeds, whole grains, fruits and vegetables – during the recovery phase of training can help most people prevent the adverse effects of high-intensity exercise and optimize performance.
However, due to and , some people lack key microbes and metabolic machinery needed to convert and into useful molecules the body can use. This shortage may explain why some healthy foods and diets might not be beneficial or .
Healthy diets might then benefit from reintroducing key microbes into the gastrointestinal tract. Research has shown that specific can improve barrier function, reduce systemic inflammation and potentially enhance athletic performance by of high-intensity exercise. An alternative approach is to increase consumption of , such as yogurt and pickled vegetables, which can .
In some cases, healthy foods might also be complemented by directly providing the body the key metabolites that microbes produce. Research shows that these metabolites – also called or – enhance . Some postbiotics also function as prebiotics that and .
From research to podium
While the benefits of nutrition targeting for general health are increasingly clear, this approach is still in the early days of exploration in endurance sports.
For the occasional exerciser and weekend warrior, that support the could be quite helpful. These strategies have the potential to improve performance, protect against adverse training effects and prevent chronic health conditions like obesity, cancer and Alzheimer’s disease.
For elite athletes seeking even the smallest of improvements in an already finely tuned training regimen, further research into the gut microbiome’s influence on performance might be invaluable. In a highly competitive field where nothing can be left off the table – or in the cupboard – such interventions might just be the deciding factor between finishing on the podium or off it.