Can Your Microbiome Improve Your Athletic Endurance

Mitochondria are the tiny but powerful energy-generating structures within most of the cells of our body.  One cell can contain hundreds or even thousands of mitochondria. (1)  It is now well accepted that one of the main reasons for variations in the endurance performance of individuals is the characteristics of their mitochondria. (2)

Many efforts have been made to enhance the performance of mitochondria.  Endurance athletes such as marathon runners and racers in cycling, rowing and swimming have long utilized many tools to this end.  Beneficial stresses found in exercise (3), alterations in nutrition (4) and sleep (5) as well as spending time at higher altitudes (6) and the application of both cold (7) and heat (8), can positively affect the number, health and structure of the mitochondria within the cells of muscles and the rest of the body.  Recently another positive influence has become clear, and that is the role of the gut microbiome on mitochondria. (1)

Note:  The gut microbiome is the community of microorganisms such as bacteria, yeast, and fungi that live in our gastrointestinal systems.

 Until recently, mitochondria were simply known as the creators of power for cells.  However, new discoveries have shown that they are involved in much more than simply the production of energy.  Today we understand that mitochondria play significant roles in the health and longevity of their host, in the survival and death of cells, in the development of various diseases and in adaption to endurance exercise.  (2)

Mitochondria are descendants of the earliest primordial aerobic bacteria that formed the first symbiotic partnership with ancient anaerobic microbes.  This stable partnership is capable of producing energy, with or without oxygen, and their host gathers the needed nutrients for its production.  In the beginning the host was likely another single-celled microbe but the stage had been set for a new framework of collaboration between the microbial world and multi-celled creatures. As more complicated organisms developed and evolved, systems such as networks of nerves, allowing communication between distant cells, and intricate processes like metabolism and the immune system emerged.  The culmination of all this can be seen in present day creatures of the earth including humans who thrive in mutually beneficial affiliations with their vast and diverse microbiota, most of which resides in the gut.  In fact, the genetic diversity of our microbiota far outweighs that of our own genes.  And in sheer numbers, the quantity of cells in our microbiome is roughly equivalent to the total number of human cells making up all the rest of our body.  The health of our human microbiome is now recognized as one of the most important factors for general human health and well-being.  And all this began with the ancient pairing of primordial bacteria.  (9)

Notes:  Primordial means existing at or since the beginning of the world or the universe, or, in biological terms, belonging to or characteristic of the earliest stage of development of an organism. Aerobic bacteria are those that grow in the presence of oxygen. 

Anaerobic bacteria do not require oxygen to grow.

A symbiotic partnership is a close living relationship between organisms from different species, usually with benefits to one or both of the individuals involved.

 How can we assist our mitochondria to become more efficient at converting calories into the energy that is required for the contraction of muscles and other bodily functions?  A healthy microbiome in the gut is in continual communication with the mitochondria in cells throughout the body.  The gut microbiome thrives on undigested bits of whole foods that have made their way virtually unchanged all the way down into the colon, the furthermost part of the large intestine.  Important healthy food nutrients found in these food pieces include fiber (only present in plant-sourced foods), polyunsaturated fats (beneficial fats from whole foods such as nuts, seeds and avocados) and polyphenols (phytochemicals which are beneficial compounds produced by plants for their own protection).  Metabolism of these healthful food components by the microbes in the microbiome produces valuable short-chain fatty acids such as butyrate as well as other helpful compounds like conjugated linoleic acid and urolithin A.  These elements have been shown to increase the number, the structure and the health of mitochondria in cells, and are specifically associated with improved muscle strength and endurance.  (9,10)

Studies illuminate the difference between the gut microbiomes of endurance athletes compared to those of the general population noting that higher amounts of butyrate are present in the intestines of endurance athletes.  Higher butyrate levels are associated with greater VO2max, the ability of muscles to consume oxygen during intense exercise, a measure of aerobic fitness and endurance.  (10)

 Whether you’re an athlete looking for better endurance, or simply someone wanting to improve your general health, engaging the help of your gut microbiome is really quite simple.  (1)

• Eat whole, non-processed foods sourced mostly from plants. Foods that positively affect your microbiome include beans, whole grains, fruits, vegetables, nuts and seeds.
• Limit intake of animal-sourced foods.
• Avoid ultra-processed foods.  They have had most of their fiber, healthy fats and phytochemicals removed during processing and potentially damaging additives added in.  Examples of additives are emulsifiers (meant to improve the taste and appearance of the food product), stabilizers and preservatives, colours and flavours, hydrolyzed proteins (proteins that have been treated with enzymes or acid to break them down into smaller peptide chains), saturated and hydrogenated fats, refined sugars, and salt. Such additives appear to have deleterious effects on the gut microbiome and the thin membrane lining the gut that keeps harmful intestinal contents from entering the bloodstream.  Food additives are also linked to colorectal cancer, irritable bowel syndrome, and inflammatory bowel disease as well as systemic inflammation (inflammation throughout the body) which is associated with cancer, autoimmune conditions, metabolic disease and neurodegenerative diseases. (11)

 

SOURCES:

1  https://theconversation.com/athletes-looking-for-a-competitive-edge-may-find-it-within-their-gut-microbiome-234979

2  Eynon, N., Morán, M., Birk, R., Lucia, A.  The champions’ mitochondria: is it genetically determined? A review on mitochondrial DNA and elite athletic performance.  Physiological Genomics. 2011; 43(13):789-798.

3  Wu, LH., Chang, SC., Fu, TC. et al. High-intensity Interval Training Improves Mitochondrial Function and Suppresses Thrombin Generation in Platelets undergoing Hypoxic Stress. Sci Rep 7, 4191 (2017). https://doi.org/10.1038/s41598-017-04035-7.

4  Kyriazis, I.D., Vassi, E., Alvanou, M., Angelakis, C., Skaperda, Z., Tekos, F., Garikipati, V.N.S., Spandidos, D.A., Kouretas, D. The impact of diet upon mitochondrial physiology (Review). Int J Mol Med. 2022 Nov;50(5):135. Doi: 10.3892/ijmm.2022.5191. Epub 2022 Sep 21. PMID: 36129147; PMCID: PMC9542544.

5  Haynes, P.R., Pyfrom, E.S., Li, Y. et al. A neuron–glia lipid metabolic cycle couples daily sleep to mitochondrial homeostasis. Nat Neurosci 27, 666–678 (2024). https://doi.org/10.1038/s41593-023-01568-1

6  Jacobs, R.A., Lundby, A.-K.M., Fenk, S., Gehrig, S., Siebenmann, C., Flück, D., Kirk, N., Hilty, M.P. and Lundby, C. Twenty-eight days of exposure to 3454 m increases mitochondrial volume density in human skeletal muscle. J Physiol. 2016. 594: 1151-1166. https://doi.org/10.1113/JP271118.

7  Chung, N., Park, J., Lim, K.  The effects of exercise and cold exposure on mitochondrial biogenesis in skeletal muscle and white adipose tissue.  Phys Act Nutr. 2017;21(2):39-47.   DOI:https://doi.org/10.20463/jenb.2017.0020

8  Tamura, Y., Matsunaga, Y.,  Masuda, H., Takahashi, Y., Takahashi, Y., Terada, S., Hoshino, D., Hatta, H.  Postexercise whole body heat stress additively enhances endurance training-induced mitochondrial adaptations in mouse skeletal muscle.  American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 2014 307:7, R931-R943.

9  Franco-Obregón, A., Gilbert, J.A. The microbiome-mitochondrion connection: Common ancestries, common mechanisms, common goals. 2017. mSystems. 2:e00018-17. https://doi.org/10.1128/mSystems.00018-17

10  Durk, R.P., Castillo, E., Márquez-Magaña, L., Grosicki, G.J., Bolter, N.D., Lee, C.M., Bagley, J.R.  Gut Microbiota Composition Is Related to Cardiorespiratory Fitness in Healthy Young Adults.  2018. International Journal of Sport Nutrition and Exercise Metabolism. 29(3): 249-253. Doi:https://doi.org/10.1123/ijsnem.2018-0024

11  Whelan, K., Bancil, A.S., Lindsay, J.O. et al. Ultra-processed foods and food additives in gut health and disease. Nat Rev Gastroenterol Hepatol 21, 406–427 (2024). https://doi.org/10.1038/s41575-024-00893-5.