It’s one of those ironies of life: You are doing something healthy and you still get sick. In this case, the step toward better health is endurance running. And the ailment is diarrhea, occasionally a side effect of what’s happening to your digestive system as you log the miles. Luckily, though, you can usually recover within a day or two.
If you’re wondering how common it is, though, browse the blogs and online forums for active people and habitual runners and you’ll see that “runner’s diarrhea” is not taken lightly -- even for those humorously referring to it as “runner’s trots.” In fact, those engaged in the conversation are seeking answers to a problem that can plague them while training, as well during and after a big race.
Why does it happen? The answers might have to do with blood circulation, any food and drink you have consumed, or just how accustomed your body is to the hard work of endurance running. Experts theorize that during intense exercise, oxygen-rich blood rushes to where it’s needed -- in the legs, heart and lungs -- sometimes shortchanging the intestines. As explained in a July 7, 2011, health story in the Bend (Oregon) Bulletin, the gut becomes irritated, and the jarring movement in the act of running doesn’t help the situation.
Another cause might have to do with carbohydrate-loading. Whether you are consuming naturally high-carb foods or energy gels and bars, you might be straining your digestive system, which wants to quickly dilute the carbs. The result can be watery diarrhea.
Other considerations include dehydration, hormonal changes and a bacterial imbalance, according to the article.
An article by the Mayo Clinic offers a number of suggestions for preventing runner’s diarrhea, mostly having to do with limiting certain food and drink in the days and hours leading up to a long-distance race. For instance, at least one day before running, limit or avoid high-fiber foods, the site said. Also, for three to six hours before running, limit or avoid caffeine and high-fat foods.