We all know that exercise does a body good. But as with any good habit, sometimes overdoing it can yield less desirable outcomes. Too much exercise, or exercising strenuously for too long a period of time, might end up hurting your gut.
Most people who exercise regularly know their body pretty well. Some people need fuel before they exercise, but if you eat early in the morning before a workout, it may stimulate your need to eliminate your bowels at an inopportune time. A cup of coffee can have that effect, as well, so most people familiar with their own bodies will time their food or beverage intake so that bathroom needs won’t interfere with the workout.
Be that as it may, after reviewing a number of studies, researchers have concluded that individuals who exercise excessively may be more prone to acute or chronic intestinal issues.
The research data was gathered from several sources including PubMed, EBSCO, Web of Science, SPORTS discus and Ovid Medline. The researchers looked for studies that focused on how “acute exercise” impacted markers of gastrointestinal injury, permeability, endotoxaemia, motility and malabsorption in otherwise healthy individuals, and in individuals who already had gastrointestinal diseases and disorders like irritable bowel syndrome (IBS).
What did the researchers consider “excessive exercise?” The study suggested that two hours of exercise, with the person working out at 60 percent of VO2max, seemed to instigate gut disturbances. (VO2max is a calculation that measures the amount of oxygen consumed during “all out” intense exercise. It is most accurately measured using information fed into a computer while a person is exercising and wearing a special mask. You can also approximate VO2max.) Those gut disturbances were actually due to damage in the gut cells, which when they become injured tend to leak fluids ("leaky gut") allowing pathogenic endotoxins (the bad microbes of the gut) to pass from the intestine into the blood stream.
Your gut is naturally porous, which allows it to absorb nutrients. When that intestinal lining is damaged, it allows large molecules (macromolecules) to escape your digestive tract and leak into the bloodstream, hence the term leaky gut. An individual with leaky gut typically experiences inflammation along parts of the intestinal lining, bloating, stool changes (often unpleasant diarrhea) and fatigue. It’s not an easy diagnosis to make. Based on this research, it should be on a doctor’s radar if the patient reveals a history of excessive or strenuous exercise.
In fact, the researchers observed that as exercise intensity and duration continue, the indices for intestinal injury increase and there is impairment of intestinal emptying, slowing of food transit time and malabsorption. If you then add heat and the stress that running full throttle can put on one’s body, those factors combined can increase frequency and intensity of the gastrointestinal issues.
If this occurs on a regular basis, it can lead to multiple acute or a persistent chronic series of health complications. This leaky gut phenomenon occurs regardless of the fitness level of the individual. In other words, being more fit doesn’t protect you from this complication. Having leaky gut can put an exerciser out of commission, since unexpected bowel symptoms can be a deal breaker, especially if you run or bike long distances outdoors. Symptoms can hit when you find yourself far away from bathroom facilities.
The researchers also noted that subjects in the studies who were already diagnosed with irritable bowel syndrome seemed to benefit from low to moderate exercise, and also seemed to tolerate this level of exercise. Though these subjects were not subjected to strenuous exercise, the implications from the data collected suggest that they might be especially vulnerable to leaky gut and complications if they further increase the intensity of their workouts.
It’s worth noting that leaky gut can be associated with other conditions. It has been linked to autoimmune diseases, gluten intolerance, food sensitivities (which can cause the initial inflammation in the gut), and it may contribute to acne or worsen insulin resistance because of its inflammatory nature. People tend to suffer with leaky gut for years, living with symptoms until the symptoms become intolerable and someone finally figures out the diagnosis and helps them to remove the trigger(s).
Leaky gut is usually reversible. Remove the cause and the intestine, over time, can self-repair and become healthy again. Some experts recommend a glutamine supplement, though solid research is not available. Glutamine is an essential amino acid that offsets inflammation and also helps to fuel the cells that line the intestine, helping them to regenerate. Of course, probiotics may also help to rebalance you gut microbiome. Always consult with your doctor before beginning any treatment programs. If you notice increasing symptoms and you are an avid exerciser, keep this diagnosis on your radar.