The Athlete’s Gut: Why Things Go Wrong and What to Do About It

Years ago, my own gut problems motivated me to seek answers outside the existing medical establishment, and with the help of my wife Julie I was able to get my diet and health back on track. Having now worked with thousands of athletes on their own health challenges and performance goals, it’s clear there are specific pitfalls that can accompany a high-level training regimen.

On this podcast, NBT Scientific Director and coach Megan Hall is with me to discuss the latest science and clinical practice on the athlete’s gut. She talks about the importance of having a healthy GI system, why athletes struggle in this area, and specifically what to do when problems arise. We also discuss what I did to regain my own gut health.

Be sure to see the end of the show notes for the outline Megan wrote to prepare for this podcast. It’s an excellent resource for anyone seeking solutions for their own gut problems.

Here’s the outline of this interview with Megan Hall:

[00:00:54] Podcast: Microbiome Myths and Misconceptions, with Lucy Mailing.

[00:01:40] The importance of gut health.

[00:03:13] Podcasts focusing on gut health, with Michael Ruscio, Jason Hawrelak, and Lauren Petersen.

[00:03:51] Study: Lupien-Meilleur, Joseph, et al. "The interplay between the gut microbiota and gastrointestinal peptides: potential outcomes on the regulation of glucose control." Canadian Journal of Diabetes (2019).

[00:04:12] Gut-muscle axis; Studies: Ticinesi, Andrea, et al. "Aging gut microbiota at the cross-road between nutrition, physical frailty, and sarcopenia: is there a gut–muscle axis?." Nutrients 9.12 (2017): 1303; and Lustgarten, Michael Sandy. "The role of the gut microbiome on skeletal muscle mass and physical function: 2019 update." Frontiers in Physiology 10 (2019): 1435. 

[00:05:43] Why athletes struggle with gut health; Studies: Costa, R. J. S., et al. "Systematic review: exercise‐induced gastrointestinal syndrome—implications for health and intestinal disease." Alimentary pharmacology & therapeutics 46.3 (2017): 246-265; and Clark, Allison, and Núria Mach. "Exercise-induced stress behavior, gut-microbiota-brain axis and diet: a systematic review for athletes." Journal of the International Society of Sports Nutrition 13.1 (2016): 43.

[00:06:59] Article: de Oliveira, Erick P. "Runner's diarrhea: what is it, what causes it, and how can it be prevented?." Current opinion in gastroenterology 33.1 (2017): 41-46.

[00:07:27] The 3 main causes of exercise-induced diarrhea: GI ischemia and reperfusion, mechanical and nutritional.

[00:13:25] UCAN SuperStarch.

[00:15:03] FODMAP fibers can increase gut symptoms; Study: Lis, Dana M., et al. "Low FODMAP: a preliminary strategy to reduce gastrointestinal distress in athletes." Medicine & Science in Sports & Exercise 50.1 (2018): 116-123.

[00:17:30] Exercise-induced endotoxemia and ischemic injuries; Lipopolysaccharide (LPS)

[00:18:08] Podcast: A Statin Nation: Damaging Millions in a Brave New Post-health World, with Malcolm Kendrick.

[00:19:05] Nutrition and immune system in athletes; Studies: 1, 2, 3, 4.

[00:20:03] Common gut symptoms we see.

[00:21:37] Nutrient deficiencies and overloads: zinc, magnesium, iron.

[00:22:27] Iron overload impedes cardiovascular benefits of exercise; Study: Rossi, Emilly Martinelli, et al. "Chronic Iron Overload Restrains the Benefits of Aerobic Exercise to the Vasculature." Biological Trace Element Research (2020): 1-14.

[00:25:08] Hepcidin; exercise increases hepcidin, which can lead to iron deficiency; Study: Goto, Kazushige, et al. "Resistance exercise causes greater serum hepcidin elevation than endurance (cycling) exercise." Plos one 15.2 (2020): e0228766.

[00:27:55] What to do about GI symptoms.

[00:28:07] Dr. Josh Turknett’s 4-Quadrant Model, described in this podcast: How to Win at Angry Birds: The Ancestral Paradigm for a Therapeutic Revolution.

[00:28:19] Dietary manipulations; Autoimmune Protocol (AIP).

[00:29:30] How Chris fixed his gut.

[00:30:07] Book: The Paleo Diet for Athletes by Loren Cordain, PhD.

[00:32:41] Lundburg rice tests for arsenic.

[00:32:59] Training fuel: Carb + protein + fat vs. simple carbs alone.

[00:37:18] Ultramarathon runners still in ketosis with up to 600g carbohydrate per day; Study: Edwards, Kate H., Bradley T. Elliott, and Cecilia M. Kitic. "Carbohydrate intake and ketosis in self-sufficient multi-stage ultramarathon runners." Journal of Sports Sciences 38.4 (2020): 366-374.

[00:38:00] Team Sky’s James P Morton on promoting endurance training adaptation in skeletal muscle by nutritional manipulation; Study: Hawley, John A., and James P. Morton. "Ramping up the signal: promoting endurance training adaptation in skeletal muscle by nutritional manipulation." Clinical and Experimental Pharmacology and Physiology 41.8 (2014): 608-613. Also see article: The IRONMAN Guide to Ketosis, by Megan Hall and Tommy Wood.

[00:38:24] “Sleep-low” strategy; Study: Marquet, Laurie-Anne, et al. "Enhanced endurance performance by periodization of carbohydrate intake:“sleep low” strategy." Medicine & Science in Sports & Exercise 48.4 (2016): 663-672.

[00:40:23] Probiotics; Study: Wosinska, Laura, et al. "The Potential Impact of Probiotics on the Gut Microbiome of Athletes." Nutrients 11.10 (2019): 2270; Serum-derived Bovine Immunoglobulin in SBI Protect.

[00:40:57] Testing if all else fails: blood, stool, Organic Acids Test (OAT).

[00:43:05] Basic blood chemistry tests for gut health.

[00:47:32] Gut microbiome testing; Onegevity Gutbio test.

[00:48:44] Treatment for gut pathology.

[00:49:08] Jason Hawrelak’s Probiotic Advisor.

[00:49:48] Podcast: How to Manage Stress, with Simon Marshall, PhD.

[00:50:52] Dietary fat causing intestinal permeability.

[00:52:04] Blog post: Is a high-fat or ketogenic diet bad for your gut? by Lucy Mailing.

[00:54:44] Getting enough calories.

[00:55:00] Relative Energy Deficiency in Sport (RED-S); Podcast: How to Identify and Treat Relative Energy Deficiency in Sport (RED-S), with Nicky Keay.

[00:55:10] Studies on the detrimental effects of energy deficiency in athletes: 1. Torstveit, Monica Klungland, et al. "Within-day energy deficiency and metabolic perturbation in male endurance athletes." International journal of sport nutrition and exercise metabolism 28.4 (2018): 419-427 and 2. Fahrenholtz, Ida Lysdahl, et al. "Within‐day energy deficiency and reproductive function in female endurance athletes." Scandinavian journal of medicine & science in sports 28.3 (2018): 1139-1146.

[00:56:35] Study: Hough, John, et al. "Daily running exercise may induce incomplete energy intake compensation: a 7-day crossover trial." Applied Physiology, Nutrition, and Metabolism 45.4 (2020): 446-449.

[01:00:18] Fiber - timing and type.

[01:02:27] Orthorexia.

[01:05:02] Only 12% of Americans are metabolically healthy; Study: Araújo, Joana, Jianwen Cai, and June Stevens. "Prevalence of Optimal Metabolic Health in American Adults: National Health and Nutrition Examination Survey 2009–2016." Metabolic syndrome and related disorders 17.1 (2019): 46-52.

[01:06:40]  Become an NBT Patron and gain access to the Elite Performance Members Club Forum.

[01:07:05] Megan's outline for this podcast.