By Rehan Jalali Updated on October 27, 2022

Gut Check: Maximizing Digestive Health For Athletic Performance

Picture for Gut Check: Maximizing Digestive Health For Athletic Performance

By: Rehan Jalali, C.S.N.

Every single thing we put in our mouth can influence the great microbial ecosystem we have inside us. And like a marriage, it could be for better or for worse! As athletes, we are focused on increasing performance, lean muscle, strength, power, explosiveness, and even maintaining a six-pack! But what if all of this could be enhanced (or decreased) by the health of our gut and digestive system. This is something that rarely gets the attention it deserves from athletes. In fact, most of the athletes I work with rarely even consider healthy gut flora as a way to enhance performance. It’s all about the external physical gains! Athletes are always preaching about having a strong core. But, it’s the inside core that they should be taking about. You can think of the gut microbiome as an ecosystem of over 100 trillion microbes that have the power to regulate immune function, reduce illness/sickness (hard to train when you’re sick), enhance exercise performance, improve recovery, support brain function, regulate metabolism, and even help lower inflammation. We need to support the good microbes and starve the bad bacteria in our gut. Let’s take a journey into our gut and investigate this extremely important part of our body.

Gut Basics

Before diving into the deep end on the benefits of a healthy gut for athletes, let’s review the basics. The gut microbiome consists of bacteria (good and bad), viruses, protozoa, fungi, and microorganisms and their respective genetic material found in the GI (gastrointestinal) tract. It literally extends from the mouth to the colon. The gut microbiota plays an important role in nutrient and mineral absorption, synthesis of enzymes, vitamins and amino acids, and production of short-chain fatty acids (SCFAs). Bacteria is found throughout the human body, including oral cavity, placenta, vagina, skin, and GI tract. But the most the of bacteria reside within the GI tract, with the majority housed in the colon. The gut microbiome expresses over a whopping 3 million genes. When you eat certain foods, gut fermentation produces byproducts acetate, propionate, and butyrate which are important for gut health and provide energy, enhance epithelial barrier integrity, and provide immunomodulation and protection against pathogens—there’s that immune health thing again! There are Prebiotics and Probiotics. Prebiotics feed the good microbes, mainly with fiber and probiotics are the actual bacteria. That’s why it is important to consume both. The idea is to get rid of the bad or harmful bacteria and replace the gut lining with the good. The gut microbiome is affected by a variety of factors including diet, stress, environment, medications, age, exercise, and even birth and infant feeding history. Scientists have actually established a brain-gut axis mediated mainly by the Vagus nerve. This important nerve establishes one of the connections between the brain and the GI tract and sends information about the state of gut affairs to the brain. It can play a huge role in mood and anxiety disorders. That’s why there is some evidence that good gut bacteria can have beneficial effects on mood/depression and anxiety, partly by affecting the activity of the vagus nerve. Viva Las Vagus!

Gut health and Athletes

Numerous research studies have shown the immense benefits of a healthy gut (including supplementation with probiotics) for athletes. A study published just last month in football payers showed that daily probiotics supplementation (improving gut health) “may have the potential to modulate the brain waves namely, theta (relaxation) and delta (attention) for better training, brain function, and psychological improvement to exercise.” As we know, mental focus and clarity are critical for athletes to function at their very best and having a healthy gut ensures that this happens. Other studies in athletes show that taking probiotics and prebiotics provides positive results in terms of performance, recovery, immune health, and even hormone function—indicating that the microbiota acts like an endocrine organ (e.g. secreting serotonin, dopamine or other neurotransmitters) and may control the HPA axis in athletes. This can have a massive impact on short and long term athletic performance. Another thing that is common in some athletes is over-training or over-reaching and some research indicates that this can have a negative impact on gut health. But good news; Taking the right probiotics (and Prebiotics) can reduce this unwanted effect and improve gut function. Another issue with athletes is inflammation and a healthy gut has been shown to reduce it. In fact, a metabolite of tryptophan called Indole-3-Lactic Acid (produced from the probiotic bifidobacterium longum) can have an anti-inflammatory effect.

Another way to look at it is that training can actually improve digestive health. There is accumulating evidence that physical fitness positively influences the gut microbiome and consequently promotes health. Exercise-induced alterations in the gut microbiome can influence health parameters critical to athletic performance. And lower susceptibility to infection, inflammatory response and improve tissue repair. I think you get the point: Maintenance of a healthy gut microbiome is essential for an athlete's health, training, and performance.
According to a position paper from the ISSN (International Society of Sports Nutrition), “Intense, prolonged exercise, especially in the heat, has been shown to increase gut permeability which potentially can result in systemic toxemia. Specific probiotic strains can improve the integrity of the gut-barrier function in athletes. Preclinical and early human research has shown potential probiotic benefits relevant to an athletic population that include improved body composition and lean body mass, normalizing age-related declines in testosterone, reductions in cortisol levels indicating improved responses to a physical or mental stressor, reduction of exercise-induced lactate, and increased neurotransmitter synthesis, cognition and mood.”

I rest my case for athletes improving gut health your honor!


ZMA™ is the creation of Mastermind Victor Conte. It’s a special combination of zinc, magnesium, and vitamin B-6. The zinc in this product is specifically formulated as zinc aspartate and zinc mono L-methionine which makes it incredibly bioavailable because of the two forms of chelates. The magnesium is found in a chelated form bound to aspartate which makes it highly bioavailable as well. The final piece to the ZMA formula is vitamin B-6 which is also known as pyridoxine. A review study published in the Journal of Gastrointestinal and Digestive System described in detail the benefits of zinc in regulating gut epithelial wall and positively modifying gut microbiome. All good news for those looking to upgrade their gut health. Another study showed that zinc supplementation can resolve small intestine permeability alterations which can help with leaky gut and even Crohn’s disease. Vitamin b-6 is also important for healthy gut bacteria and a deficiency (although unlikely) can be problematic. And finally magnesium deficiency has been shown to adversely affect gut health by causing a decrease in gut microbial diversity.

Tips to Improve Digestive Health

• Exercise regularly - Even walking can be beneficial to gut health according to some research.
• Eat high fiber foods - They work as Prebiotics to feed good bacteria. These include Apples, broccoli, figs, dates, lentils, black beans, oatmeal, olives, almonds, raspberries, and kale.
• Eat fermented or cultured foods like fermented sauerkraut, kimchi, kefir, and yogurt.
• Take Probiotics - Looks for a minimum 20 billion CFU (colony forming units). A few
good strains include lactobacillus acidophilus and bifidobacterium bifidum.
• Reduce stress
• Take coconut oil and Arabinogalactan
• Take ZMA - We discussed the importance of Zinc, Vitamin B-6 and magnesium for gut health
• Take Vitamin D3 as it’s been shown to modulate beneficial bacteria in the gut.

Things That Negatively Impact Gut Health—Reduce or Avoid!

• Stress
• Antibiotics
• Excess sugar
• Highly Processed foods
• Refined oils and fats
• Anti-inflammatory medications (ibuprofen, etc)
• Acid blockers/Acid reflux medicines
• Fast food (bye bye Mickey D’s!)

So, take good care of your gut and it will undoubtedly take good care of you!

References: microbiome-proposed-mechanisms-and-evidence-from-the- literature-2161-069X-1000548-99439.html


About Author
Gut Check: Maximizing Digestive Health For Athletic Performance
Rehan Jalali is an internationally recognized Certified Sports Nutritionist (C.S.N.) based in Beverly Hills, Ca. He is the author of several books including “The Six Pack Diet Plan” (available on Amazon) and the “Sports Supplement Buyers Guide”. He is co-author of “The Bodybuilding Supplement Guide.” His upcoming books include “The Super Hero Diet Plan” and the “Ultimate Guide to Women’s Fitness”. As a Nutrition and Dietary Supplement expert, he has been featured in several movies including “Bigger, Stronger, Faster” and the recent “SUPPS: The Movie” on Amazon Prime Video.