How to Avoid Having Diarrhea During Runs

portable toilets at Central Park

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It's not unusual for runners to experience gastrointestinal symptoms including cramps and diarrhea, also known as "runner's trots", during longer runs. These symptoms are likely the result of blood flow being direct away from the intestines to support active skeletal muscles in the legs and torso. In some athletes, there may be a dietary component as well.

Pay Attention to What and How You Eat

This issue is more common in novice runners, so it may disappear as you become more fit. Try to avoid eating for at least two hours before you exercise -- the presence of food in the stomach will make things worse or contribute to the problem. It helps to avoid high-fiber foods like fruit, vegetables, legumes, and whole grains, which empty more slowly from the stomach.

Coffee and tea contain caffeine, which can increase intestinal contractions, worsen intestinal cramping, and act as a weak diuretic that promotes a need to urinate. Finally, it is essential for runners to remain well hydrated. Though higher in sugar than necessary, available sports drinks like Gatorade and Powerade contain the water and electrolytes necessary to replace those lost in your sweat. Before running, especially long runs, try to stick to foods that are more binding, such as white rice or bananas.

You might want to consider limiting your intake of milk and dairy products for a day or two before running if you have issues with lactose intolerance. The protein found in dairy products takes a long time to digest. If you've ever had problems with lactose intolerance or you're susceptible to diarrhea, avoid dairy altogether for the two days leading up to a long run or race.

Be aware of your bowel habits and try to time your workouts for after such movement times. If you're running in the morning, give yourself plenty of time to take care of business before you start running.

You should also consider speaking with your doctor about any symptoms that you experience while running. Depending on what you describe, medical testing may be warranted. Your doctor may also be able to recommend additional dietary or drug therapies that may be useful.

Plan Your Running Route With Bathrooms

It's comforting to know where you can make a pit stop during your runs. Try to plan your long runs along routes where you know bathrooms are accessible. It also doesn't hurt to carry some spare toilet paper in your pocket or running belt in case of an emergency. And if you need to make a pit stop on race day, don't worry. You'll find plenty of porta-johns at the start and along the racecourse. They'll be marked on the course map, and you'll be able to easily see (and maybe smell!) them along the course. In most cases, you can find them near the water stops.

Closing Thoughts

If you've tried many different strategies with no luck, you may want to try an over-the-counter anti-diarrhea product such as Imodium. It is safe to use for exercise-induced diarrhea, but you shouldn't make a habit of using it. Save it for races or special events where you know there won't be any port-a-johns available.

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