Got Gut Issues? Exercise Can Make it Worse

It was a Tuesday afternoon and I should have been at work.  Instead I was on the couch, again, in the fetal position feeling fatigued and crampy. The biggest question on my mind, “Why me? I’m trying so hard to do everything right!” I had started to rid my gut of a bunch of parasites and bad bacteria, and I was eating exceptionally healthy and hitting the gym (hard) 5-6 times a week. But gut healing just wasn’t happening and I’d added a ridiculous 10 kg’s and two stretchy-pants sizes in less than two months on my strict regime.

It was 2014 and I was about to learn the pitfalls of too much exercise when it comes to gut healing.

So today we’re talking about:
>  Why too much exercise can wreck your guts and make you fatter
>  The link between exercise, cortisol dysregulation and leaky gut
>  The number 1 type of exercise proven to enhance gut healing

There is no disputing that physical exercise is a really important part of living a healthy life. The benefits of exercise, especially for prevention of chronic diseases such as cardiovascular disease, diabetes, hypertension, obesity, depression and osteoporosis are well documented and accepted (1). A variety of studies have also shown that exercise improves psychological well-being and mood (2, 3) as well as resilience to chronic and acute stress (4, 5).

There is also evidence that moderate exercise can improve gut barrier function and potentially help prevent inflammatory bowel disease (6, 7). Contracting your muscles during exercise releases anti-inflammatory myokines, which help to block the release of pro-inflammatory cytokines produced by visceral fat (fat around the middle).  These cytokines are thought to contribute to the onset of INFLAMMATORY bowel disease and other gut disorders. Studies on mice have also shown that moderate exercise reduces chronic stress-induced Leaky Gut (6).

So, exercise is great and the more the better? Not so fast!

Gut distress, such as diarrhoea, cramping, vomiting, nausea and gastric pain are common among athletes during training and competition (8). See, when it comes to exercise, there’s a happy medium for optimal gut function and healing. While not exercising enough is detrimental to your health, too much (too long duration, frequency or intensity) can also negatively impact your health and healing. Basically, strenuous exercise is linked to dysregulated cortisol, immune system suppression and intestinal hyperpermeability (Leaky Gut) (9, 10, 8).

The SCIENCE of exercise, cortisol dysregulation and leaky gut

So, let’s geek out on the science (just a heads up that you can skip this if you’re short on time). Intense exercise is a stress on the body and just like any other kind of stress, activates the Hypothalamus-Pituitary-Adrenal (HPA) Axis, better known as the ‘fight-or-flight’ response. This then causes the release of two important hormones that directly affect your gut. The first is cortisol, the master stress hormone, which is known to suppress the immune system, decreases gut motility (i.e. can cause constipation), inhibit pancreatic enzyme secretion and gallbladder function which are essential for digestion, decrease intestinal blood flow and even directly impact the gut microbiome. Basically this means chronically elevated cortisol levels are not good for gut function or gut healing, not to mention it is linked to obesity and weight gain (11).

The second hormone released under the stress of intense exercise is corticotropin-releasing hormone (CRH). When released, CRH increases the permeability (leakiness) of the intestines (Leaky Gut) through the activation of mast cells and the protein claudin-2 (12, 13). And if you read my blog post on Leaky Gut, you’ll know that there will be no gut healing while those guts are leaking…

Exercise only works if it’s not stressful

The key takeaway is that if you are trying to heal a damaged gut, exercise ONLY works if it’s not an added stressor. In a study on mice, researchers found that if they let the mice run in their own time, they had less inflammation and intestinal damage. But, if the mice were forced to run on a treadmill, they experienced increased inflammation and gastrointestinal symptoms (14). In simple terms, if the exercise itself is a stressor, it can actually make gastrointestinal symptoms worse - a bit like endurance athletes and their ‘runner’s trots’.

So, I’ve already mentioned that moderate exercise can improve gut barrier function and potentially help prevent inflammatory bowel disease (6). But what is ‘moderate’ exercise? Well, exercises such as walking (15), pilates and yoga practices that focus on stretching, breathing and postural control all have reported positive outcomes when it comes to gut healing (16, 15, 17). If you are currently doing long runs, intense gym classes or even more strenuous forms of yoga (hot vinyasa) and pilates, I’m giving you permission to slow down a bit, and engage in more healing forms of exercise… for the moment.

And no, you’re not going to get fat

And for those worried about your weight, rest assured that reducing the stress on your body from chronic cardio or over-training is likely to actually have a positive impact on your waistline. Not only can the increase in cortisol from over-training lead to insulin resistance, increased fat storage and cause your body to burn muscle before fat, but it has also been shown to directly impact our appetite for high fat and high sugar foods (18) - not a good combination!

I know, because I’ve been there. I was diagnosed with more than 5 intestinal pathogens, adrenal insufficiency and IBS in 2014. I thought ramping up my gym regime would be a great way to stay healthy and combat the bugs. Going to the gym five to six times a week and doing a mix of weights and HIIT training, I didn’t expect to gain over 10 kgs (more than 20% of my body weight - I’m a small human) in less than two months. If you’re slogging it out at the gym, the last thing you want is to be feeling sicker and gaining body fat. The more body fat I gained, the more I trained and so the cycle continued until I was so exhausted I couldn’t get out of bed. I had damaged my guts further.

It wasn’t until I cut back on the strenuous stuff every day and replaced it with walking and yoga that I started to get my energy back and my bugs under control. The weight took a lot longer to shift.  So, take it from me, you CAN exercise too much and it CAN have a negative impact on your health and healing if you overdo it. So if you have gut healing to do, just try and chill-out, focus on your healing, stay active and know that when your digestive health is 100%, achieving any body composition goals is going to be a walk in the park.

Next steps

I really hope this has given you a better understanding about the relationship between exercise, stress and healing. You might even like to read these posts next:
> The best exercises for Irritable Bowel Syndrome or
> 12 Yoga Poses to Improve Digestion

And remember, healing the gut is a journey. If you are ready to begin yours, please head to the Work With Us page to learn more about how we work online at The Functional Gut Health Clinic with clients in many countries to test for and treat the many root causes of IBS symptoms and other GI conditions.

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