Fuel Your Fitness from the Inside Out: Optimize Your Gut Health for Better Workouts

May 5, 2024

by Cathe Friedrich

Have you ever heard the old saying “trust your gut?” Well, those words of wisdom are backed by science. Research reveals a powerful connection between the neurons in your brain and spinal cord and your gut. It’s a two-way street and one that can affect all aspects of your health and well-being, from your mood and mental clarity to how well you perform when you work out.

The Gut-Brain Axis

As mentioned, your gut and brain connect via a large nerve called the vagus nerve. The two systems also have indirect connections via hormones and the immune system. The vague nerve is a major highway that carries information between your gut and brain. Input from this giant nerve helps control muscle contractions in your gut. Such input helps you move food through your digestive tract at a controlled pace, so you can absorb nutrients efficiently. Nutrients provide energy. See the connection?

You might have heard your gut called your “second brain.” Your gut contains over one hundred million nerve cells. This group of neurons produces many of the same neurotransmitters as your brain, like serotonin, dopamine, and GABA. In fact, your gut makes over 90% of your body’s serotonin. These neurotransmitters affect your mood, sleep habits, motivation, and even how you move.

The Gut Microbiome

There’s another system called the gut microbiome, a term you hear a lot about these days. It’s home to trillions of bacteria, fungi, and other microbes that, under good circumstances, live peacefully in your gut ecosystem. These organisms produce vitamins and neurotransmitters that contribute to healthy digestion and immune function.

On the downside, the modern human gut microbiome takes a beating, thanks to an abundance of stress, processed diets, antibiotic overuse, etc. These factors damage the healthy microorganisms in our guts and reduce their diversity. This leads to a gut environment where narrower groups of microbes are dominant, some of which are harmful.

Why is this a problem? Studies show that a more diverse gut microbiome is healthier. And there’s more. A growing body of research links poor gut health to mental health disorders like anxiety and depression, as well as metabolic and inflammatory diseases.

Gut Health and Athletic Performance

So how does this all relate to your workouts? Your gut plays an indirect role in several ways:

Nutrient absorption

A balanced gut microbiome helps maximize the nutrients you extract from the food you eat. So, a healthy gut microbiome helps your muscles and brain get the fuel they need for the best performance.

Inflammation

Gut dysbiosis can make the gut lining more permeable or “leaky.” When your gut integrity is compromised, it allows toxins and even food particles to enter your bloodstream, they can trigger systemic inflammation. When you have low-grade inflammation, you have more difficulty building muscle and recovering from your workouts. You might also experience fatigue or joint pain that makes it harder to work out.

Studies show athletes have higher levels of short-chain fatty acids that help protect the gut lining from damage, thereby giving some protection against inflammation. So, exercise is your ally in preserving gut health, if you don’t overdo it.

Hydration

You absorb the fluid you take in through your gut. An inflamed, leaky gut doesn’t absorb fluids and electrolytes as well, so you’re at higher risk of dehydration. So, a healthy gut helps maximize hydration and optimize blood volume. Even a mild fluid shortfall can cause big drops in performance.

Stress Response

The gut helps regulate the body’s response to both physical and mental stress through the vagus nerve. An imbalanced microbiome can cause an exaggerated stress response and cause a surge in cortisol, a stress hormone. When your cortisol is high for prolonged periods, it triggers muscle breakdown and makes it harder to build muscle size and strength.

Sleep

The gut microbiome helps regulate circadian rhythms and sleep-wake cycles by producing neurotransmitters and hormones that impact sleep, like serotonin and melatonin. If your gut is in a state of disrepair, you may experience sleepless nights and poor sleep quality. As you know that makes it hard to deliver your best athletic performance.

Motivation

The gut-brain connection also has a substantial influence on drive and motivation. Along with fatigue, an unhealthy gut environment can sap your get-up-and-go, making it harder to push yourself during workouts.

Optimizing Gut Health for Peak Performance

A happy gut makes for a happy athlete. To keep your digestion and microbiome in top shape, focus on these habits:

Eat a wide variety of plant foods. Aim for 30+ diverse types of fruits, vegetables, whole grains, legumes, nuts, and seeds each week. The fiber and nutrients in plants contain prebiotic fiber that supports the bacteria and other microbes that support gut health.
Munch on fermented foods. Fermented foods like yogurt, kefir, kimchi, sauerkraut, and kombucha contain probiotics that make your gut a healthier ecosystem.
Limit processed foods and added sugars. Diets high in processed foods and sugar are the enemy of a healthy gut microbiome and fuel inflammation.
Manage stress. Chronic stress alters gut motility and microbiome composition. Find your dose of calm with relaxation techniques like deep breathing, meditation, and spending time in nature. Exercise is also a great stressbuster.
Prioritize sleep. Aim for 7-9 hours of quality sleep per night. The gut and brain undergo important restoration and detoxification processes during deep sleep cycles.
Stay hydrated. Drink enough water and electrolytes to keep your digestive system running smoothly. Dehydration can cause constipation and throw off the balance of fluid-loving beneficial bacteria in the gut.

Conclusion

The more you can support a diverse, balanced, and resilient gut microbiome, the better you’ll feel and perform—both when you work up a sweat and in daily life. When you take care of your gut, you’re nurturing your brain and whole-body health too. Next time you’re dragging before a workout, remember, it all starts in the gut!

References:

Mohr AE, Ralf Jäger, Carpenter KC, et al. The athletic gut microbiota. Journal of the International Society of Sports Nutrition. 2020;17(1). doi:https://doi.org/10.1186/s12970-020-00353-w
‌Sohail MU, Yassine HM, Sohail A, Thani AAA. Impact of Physical Exercise on Gut Microbiome, Inflammation, and the Pathobiology of Metabolic Disorders. Rev Diabet Stud. 2019;15:35-48. doi: 10.1900/RDS.2019.15.35. Epub 2019 Aug 4. PMID: 31380886; PMCID: PMC6760895.
Lenka Dohnalová, Patrick Lundgren, Jamie, Nitsan Goldstein, Sebastian L Wenski, Pakjira Nanudorn, Sirinthra Thiengmag, et al. “A Microbiome-Dependent Gut–Brain Pathway Regulates Motivation for Exercise.” Nature 612, no. 7941 (December 14, 2022): 739–47. https://doi.org/10.1038/s41586-022-05525-z.
Barton W, Penney NC, Cronin O, Garcia-Perez I, Molloy MG, Holmes E, Shanahan F, Cotter PD, O’Sullivan O. The microbiome of professional athletes differs from that of more sedentary subjects in composition and particularly at the functional metabolic level. Gut. 2018 Apr;67(4):625-633. doi: 10.1136/gutjnl-2016-313627. Epub 2017 Mar 30. PMID: 28360096.
“The Connection Between Physical Exercise and Gut Microbiota ….” 21 May. 2022, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9474385/.
Clauss M, Gérard P, Mosca A, Leclerc M. Interplay Between Exercise and Gut Microbiome in the Context of Human Health and Performance. Front Nutr. 2021 Jun 10;8:637010. doi: 10.3389/fnut.2021.637010. PMID: 34179053; PMCID: PMC8222532.