Few things can sabotage a workout session like the onset of diarrhea. While its cause is not perfectly understood, exercise-induced diarrhea affects fitness enthusiasts and competitive athletes alike. If you are experiencing diarrhea during or after your activity, identify the probable reason and take steps toward prevention. If the condition persists, consult with your doctor to rule out a more serious problem.
Causes of Diarrhea
Diarrhea has a number of causes completely unrelated to exercise. Before making the assumption that your physical activity is causing diarrhea, rule out a coincidence from another factor. Diarrhea can be brought on by viruses, bacteria, or parasites. Lactose-intolerance causes it. Certain medications cause it, especially antibiotics which destroy good and bad bacteria in the intestines. The artificial sweeteners, sorbitol and mannitol, found in chewing gum can also spark a bout of diarrhea. It is entirely possible that the antibiotic you have been taking for two weeks paralleled the start of your spring running program and is causing your condition, not exercise. Or perhaps the chewing gum that you love to pop on your bike rides is in fact the source of your diarrhea, not cycling.
Diarrhea and Exercise
If there is no obvious cause of the diarrhea, it could be specifically related to exercise. A study conducted at the Oklahoma Foundation for Digestive Research found that 70 percent of athletes studied reported lower bowel symptoms after exercising. Diarrhea after physical activity is likely caused by the redistribution of blood flow away from the intestines toward exercising skeletal muscles. Additionally, because dehydration can lead to diarrhea, loss of fluids while exercising may account for its onset during or after exercise.
Preventing Diarrhea When Exercising
To prevent diarrhea when exercising, focus on prudent food and beverage choices. First, drink plenty of cold fluids before, during and after exercise. (Warm liquids speed the movement of food through the intestines.) Secondly, avoid high-fiber foods such as beans, fruit, and bran before your workout. Steer clear of caffeine and high-fat foods three to six hours before physical activity. With careful experimentation, you may find that one or more of these rules can be modified to suit your individual needs. For example, maybe your gastrointestinal system can handle an apple before you run but requires you to drink your coffee once you are finished. In addition to the decisions you make regarding consumption, try decreasing the intensity and/or duration of your activity until the diarrhea improves, at which point you can gradually re-build the original parameters of your workout.
Seek Treatment if Diarrhea Continues
If you have tried to manage diarrhea on your own, tweaking your food intake and exercise sessions, consult with your doctor. You may require medical assistance in flushing bacteria or a parasite from the body. In more serious cases, diarrhea can be caused by Crohn's disease, ulcerative colitis, celiac disease, microscopic colitis, and irritable bowel syndrome. Your physician will provide you with the most appropriate solution based on the cause of your diarrhea.