Runners' Colitis and How to Prevent Flare-Ups

Nothing can ruin a good workout like the fear of having a bathroom accident, especially if you've been diagnosed with a condition that makes you prone to such problems, like runners' colitis. While this condition typically affects elite athletes who routinely run long distances, even ordinary folks who run intensely may experience flare-ups.

Two women running together
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Colitis is simply an inflammation of the colon, and runners usually experience the condition temporarily due to the intensity of their workouts.

Symptoms may last for hours, days or weeks, and runners are vulnerable because running requires the body to send oxygen-rich blood to the large muscles, a process that reroutes this blood away from other body parts, such as the gastrointestinal tract. The dehydration runners experience and the harsh movement of the body during exercise may also aggravate the GI tract, resulting in colitis.

Symptoms of the condition include gurgling, cramping and loose bowels that can certainly amp up a runner's anxiety. Runners' diarrhea, which has been linked to colitis, is the term for the group of diarrhea-related symptoms brought on by intense or prolonged exercise.

In addition to intestinal cramping or loose and frequent stools, this decidedly unpleasant phenomenon may manifest itself through fecal incontinence and (on rare occasions) rectal bleeding. These symptoms may appear during or after exercising and are most common when people engage in long-distance running.

Avoid Known Triggers

There are several identifiable factors that affect your gut’s motility, thereby increasing the frequency of intestinal contractions and resulting in diarrhea symptoms. Thus, the basic recommendations for reducing the risk of runners' diarrhea have to do with avoiding these factors:

  • Don’t eat two hours before exercise.
  • Avoid caffeine and hot drinks on the day of exercise.
  • Avoid known intestinal triggers and gas-producing foods starting the day before a big event.

Avoid Other Contributing Factors

Research performed on marathon runners has pinpointed other potential contributing factors for runners' diarrhea. The following appear to result in changes within the gastrointestinal system, changes that increase the risk of diarrhea symptoms:

  • Don't take aspirin or ibuprofen. If possible, avoid these products prior to or during exercise.
  • Stay hydrated. Adequate fluid intake is important for many aspects of health and performance while exercising, including reducing your risk of GI symptoms.

Nervous Diarrhea

Nervous diarrhea is the term for diarrhea symptoms that are experienced prior to intense exercise. You may be more at risk for nervous diarrhea if you suffer from irritable bowel syndrome (IBS), are lactose intolerant, or suffer from irregular bowel habits. Here are tips for avoiding nervous diarrhea:

  • Avoid dairy products if you think you may be lactose intolerant.
  • Learn relaxation exercises to keep your system calm prior to exercising.
  • Schedule your workouts during times when you know that your digestive system is quieter.
4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Faress A, Masood S, Mian A. Case letter: 'Runs' from a run: A case of exercise induced ischemic colitis. World J Emerg Med. 2017:8(4). doi:10.5847/wjem.j.1920–8642.2017.04.010

  2. McCoy J. 6 foods that can give you runner’s tots—and what to eat instead. Runner's World.

  3. Aschwanden C. The pill problem. Runner's World.

  4. Cleveland Clinic. Irritable bowel syndrome (IBS): Q & A.

Additional Reading

By Barbara Bolen, PhD
Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome.