Hi Runner s diarrhea is characterized by frequent, loose bowel movements during or immediately after a run. Runner s diarrhea is most common in long-distance runners. The cause of runner s diarrhea isn t clear. Contributing factors likely include the physical jostling of the organs, decreased blood flow to the intestines, changes in intestinal hormone secretion and pre-race anxiety and stress. What is clear is that food moves more quickly through the bowels of athletes in training Often, simple dietary changes can help prevent runner s diarrhea: -At least one day before running, limit or avoid high-fiber and gas-producing foods, such as beans, bran, fruit and salad. If you run every day, experiment to find a tolerable level of fiber. Otherwise, simply eat those foods after you run -At least one day before running, limit or avoid sweeteners called sugar alcohols — most often found in sugar-free candies, gum and ice cream -For three to six hours before running, limit or avoid caffeine and high-fat foods -For at least two hours before running, don t eat anything at all -Before, during and after running, drink plenty of fluids. Dehydration can lead to diarrhea. Avoid warm liquids, however, which can speed food through the digestive tract -While running, use caution with energy gels and energy bars. In some people, these products can contribute to diarrhea -If you re lactose intolerant, switch to lactose-reduced or lactose-free milk and milk products Wish You Good Health Regards Dr Sridhar K