‘Leaky Gut’ and Intense Exercise

Can it be avoided?

If you’re reading this article, odds are you enjoy exercising (or maybe you’re one of my family members who shows unconditional support for anything I’d write). Or, maybe you enjoy reading anything about gut health and are curious to know how it is impacted by intense exercise. Let me start off with a story. Long ago in a land far, far away…… ok long ago meaning like 10 years, I found myself face deep in a trash can during a lacrosse practice. Now, you may be asking, why was I face deep in said trash can? Well besides searching for some athletic ability, I was throwing up because of how intense the practice was. Long story short, I ate too much too soon prior to practice, my system wasn’t able to properly digest my food during the actual practice, so it did the next best thing, completely got rid of it.

You may remember growing up your parents saying “Don’t eat too much before your game, or before you go swimming, or before practice.” Why is that? What about eating before exercise can be harmful? Why might it also be important to wait an hour after your workout to eat? What happens to our guts during intense exercise? Or non-intense? What can we do about it?

How do I know if my gut is off?

Symptoms such as gas, bloating, constipation, diarrhea, vomiting, nausea, and abdominal pain are what lead many of us to believe that something is wrong with our gut. However, symptoms such as brain fog, joint pain, and headaches can all be related to issues going on in your gut. If you experience any of these symptoms I recommend you seek out a qualified health care provider who has training in evaluating the gut, specifically a Functional Medicine Practitioner.

Exercise has been accompanied by gut issues in anywhere from 30–90% of people depending on exercise type, intensity, and duration (1). Not to mention that a disruptive gut can have negative impacts on performance. In one study, nearly 7% of triathletes abandoned the race because of gut problems! Now, that’s not me saying that you shouldn’t exercise, but rather with more intense and/or longer duration exercise, more targeted strategies may need to be considered to optimize gut function.

Intensity is the Name of the Game

What is intense for one person may be light for another, and vice versa. A great way to tell if you’re exercising intensely is based off your breathing. If you’re breathing exclusively in and out with your mouth, as opposed to your nose, and you feel like your heart is beating ‘out of your chest’, odds are you’re exercising at a high intensity. If you feel like you can hold a conversation with someone or you’re breathing exclusively out of your nose, odds are you’re exercising at a moderate-light intensity.

Leaky gut takes place when the gut barrier that’s designed to protect us from bad things getting into the body, opens up and allows harmful substances to make their way into our systemic circulation. This can happen by way of chronic NSAID use, stress, highly processed foods, and high-intensity exercise. But I thought exercise was good for me?! How can it give me leaky gut?! How does that happen?!

Whenever we start to breath really hard our body goes into a ‘fight or flight’ mode (sympathetic) and starts to release various hormones (epinephrine and norepinephrine) that help to prepare our body for said fight. This means blood flow gets re-distributed from our intestines into the muscles in the are arms and legs (you’d rather worry about using your arms than digesting your food if you were about to fight a bear). Blood flow can be diverted away from the gut to the extremity muscles by up to 80% during intense exercise (1)! Unfortunately when our GI tract doesn’t get enough blood supply, the cells that line the gut barrier don’t get enough nutrients, so they start to die off and thus creating openings (leaky gut). Check out the figure below:

In a healthy individual or with less intense exercise, blood flow will return to the gut within 10 of stopping exercise (2). That’s why I believe a cool down is so massively important and can be so massively impactful on your gut health. Take that ten minute window to bring the heart rate down, do some static stretching, deep breathing, go for a light walk, do something where you can be completely conscious of your breath. Thus, blood flow can be returned to your gut and you can go about your day. In the next part I’ll discuss strategies to help support your gut barrier post-intense exercise, or one quick way to help bring down the intensity.

Follow Your Nose

This one is a far easier strategy and I myself incorporate this a few times per week for recovery purposes. If you want to reduce your exercise intensity, do your workout only breathing with your nose. That’s right, every inhale, and every exhale, with your nose. This will inevitably force you to lower your intensity, as breathing nasally for most people is far more difficult then breathing through your mouth. Breathing nasally also does a better job of cooling and filtering the air we breath (ever wake up with dry mouth in the morning, odds are you were mouth breathing in your sleep). It also helps create a molecule called nitric oxide, which opens up our blood vessels and allows for greater delivery of blood and oxygen.

Now for my more intense workouts or heavy weightlifting sessions, I breath through my mouth in order to create more intra-abdominal pressure, thus bracing my core and low back. But for running, mobility work, and recovery sessions I stick to exclusively nasal breathing. Try to do a 10 minute run only breathing through your nose, you might be surprised at how difficult it is!

Supporting the Gut

Now if you’re like me and very stubborn, odds are you’re going to still do intense exercise and breath through your mouth at times. I use a mix of fasting, supplements, and specific dietary nutrients to help mitigate some of the leaky gut that gets created.

I grew up reading bodybuilding articles and magazines that talked about the ‘anabolic window’, that 30–60 minute period post-workout where you had to get your protein shake in. However, in these articles there was no mention of: A) leaky gut during exercise, and B) possible food sensitives to different types of protein powders (whey, casein, and even plant-based). If you are sensitive to one of these types of proteins, and you introduce them into your body post workout before blood flow has returned to the intestines, that protein is going to make its way past the gut lining and into systemic circulation. What this means is that there’s now a protein in your blood stream that your body doesn’t recognize, or worse, recognizes it as your own tissue (think autoimmune disease). Your immune system will then mount an attack against that protein, and potentially lead to the symptoms of gas, bloating, fatigue, brain fog, joint pain, etc. Protein farts are a very real phenomenon.

Much of that anabolic window has been re-understood to now include 24–48 hours post-exercise; you are still building muscle from your Monday workout on Wednesday. It is because of this that I now fast for at least an hour post-intense workouts. This gives my gut a chance to let the blood flow return and repair itself. I still use whey protein, I just try to make sure its outside of that 60–90 minute window post-workout.

If you are training multiple times in one day, post-workout nutrition becomes highly important. In this case I’d recommend having a bone broth based substance (powder, traditional broth) or some essential amino acids (different from branched-chain, sort of). Both of which will not only help you re-build some muscle from the first workout, but provide the gut lining with the nutrients to help repair itself.

Okay, now time for the stuff everyone wants to know, what supplements can I take? In a trial done on elite endurance runners, zinc carnosine and bovine colostrum increased epithelial resistance to stress associated with intense exercise (epithelial cells are the cells that make up the gut barrier) (3). L-Glutamine has been a popular supplement in the fitness community, and it has merit. Glutamine is one of the amino acids that makes up the gut barrier, so the hope is that taking them will help to repair any damage associated with exercise. Fun fact, glutamine is also one of the most abundant amino acids in bone broth. Other herbs such as Marshmallow Root, Quercetin, Licorice Extract, and Aloe Vera Gel can all help support leaky gut.

I like to have a ‘food first’ mindset when it comes to incorporating beneficial compounds, which is why I’m such a fan of bone broth and eating the tendons from red meat. But there is always a place for more targeted supplementation. If you’re suffering from any kind of leaky gut condition and would like to know more about specific strategies, find a practitioner who will get to the root cause of your gut issues, such as a Functional Medicine Practitioner.

Go With Your Gut

I’ll be the first one to admit that I occasionally work out too much, but that’s because I enjoy it and love to push the boundaries of human potential. I get this ‘gut feeling’ every time I exercise that I’m doing what makes me happy. That can’t happen without first, giving my gut some love. That’s why I incorporate fasting periodically, avoid foods that cause me inflammation, and provide it the building blocks it needs to nourish itself. I think this is where you need to have a serious conversation with yourself and say self: Do I want to exercise just for the health benefits or do I want to go beyond that? If the answer is the latter, hopefully you found a few strategies you can incorporate into your lifestyle.

If you did enjoy this article, I’d really appreciate it if you looked at the upper left hand corner, and gave the article an applause. If you’d like further information on optimizing your gut health, living with autoimmunity, and listening to me rant, make sure to give me a follow as well or hit the email notification button to get notified whenever I publish a new article.

As always, trust in Your Gut.

Disclaimer: The contents of this article are for educational purposes only, and are not intended to diagnose or treat any condition. Do not apply any of the information in this article without first speaking with your doctor.

References

1. De Oliveira, E., Burini, R., Jeukendrup, A. (2014). Gastrointestinal complaints during exercise: Prevalence, etiology, and nutritional recommendations. Sports Medicine, 44 (Suppl 1): S79-S85.
2. Van Wijck, K., Lenaerts, K., Grootjans, J., P Wijnands, K., Poeze, M, et al. (2012). Innovative and Emerging Technologies in GI Physiology and Disease Physiology and pathophysiology of splanchnic hypoperfusion and intestinal injury during exercise: strategies for evaluation and prevention. Am J Physiol Gastrointest Liver Physiol, 303: 155–168.
3. Davison, G., Marchbank, T., March, D., Thatcher, R., Playford, R. (2016). Zinc carnosine works with bovine colostrum in truncating heavy exercise-induced increase in gut permeability in healthy volunteers. The American Journal of Clinical Nutrition, 104(2): 526–536.