With 12 laps remaining in the 2013 NCAA Division II 10,000m championship, Mansfield University's Jess Scordino felt a sudden and terrible sensation in her bowels. In an instant, she had to decide: Should she continue to race and soil her shorts or dash off the track in search of a restroom?
"There was kind of nothing I could do," Scordino says. "You either get to be All-American or you quit because you crapped yourself."
Scordino took the first option, crossing the finish line in sixth to earn her first All-America certificate. In doing so, she achieved a lifetime dream while enduring a sport-specific nightmare. A 2009 study in Current Opinion in Clinical Nutrition and Metabolic Care, "The Impact of Physical Exercise on the Gastrointestinal Tract," found that 30 to 50 percent of runners experience some type of lower gastrointestinal (GI) distress during long or intense runs, including diarrhea, abdominal cramping and an immediate urge to defecate. Frequent sufferers of "runner's trots" often find themselves forced to train indoors or on routes with numerous public rest-rooms.
"People shouldn't be hopeless and helpless," says Nancy Clark, a sports nutritionist and author of numerous books, including How to Run Twice a Day Without Injury. "A lot of people I work with, it becomes a barrier to their running," Clark says. Fortunately, the body of research is shedding more light on this once-taboo subject.
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Running is an inherently violent, jarring sport on the body. No organs feel this more than the stomach and colon. Mechanical distress causes food and waste to move through the GI tract more rapidly when a runner is exercising. At the same time, blood is shunted away from the intestines and toward working muscles, lowering their functionality. This predisposes athletes toward having lower GI problems while running but offers no solution. Instead, most experts point to other variables, including diet, dehydration, lactose and gluten intolerance or even nerves.
This list means that no catch-all cure exists for stopping runner's trots in its tracks. But before you spend thousands of dollars on extensive tests, consider these simple solutions.
DAA Industry Opt Out: Most runners find the cause of their lower GI distress is diet-related. The simplest modifications--like avoiding foods that are high in fiber or fat or contain known irritants (such as the low-calorie sweetener sorbitol) in the days leading up to an important race or workout--often keep problems at bay, Clark says. In their place, eat naturally constipating foods like white pasta, white rice and bananas.
A good way to detect food triggers is by keeping a food and bowel movement journal. Remember that for the average person, it takes between 24 and 72 hours for food to move from gut to toilet, with runners tending to be on the faster side.
One thing you don't want to do is abandon food altogether. "I've had people who are so afraid of a pit stop, they say, 'I'm not going to eat or drink anything during the marathon,'" Clark says. "Some of them get to maybe 15 or 20 miles on just air, but there's a difference between 20 miles and 26.2 miles. And the people who try to do it on air generally end up in the medical tent."
If you continue to experience frequent lower GI distress or see blood in your stool, you may want to consult a doctor, who can detect any underlying problem, says Cathy Fieseler, a sports medicine physician and ultra-runner. Lactose and gluten intolerance (including celiac disease), as well as irritable bowel syndrome, Crohn's disease and ischemic colitis, all make you more susceptible to lower GI distress. One symptom that isn't as alarming as it sounds is occult (invisible) blood detected in a stool sample. This is a fairly normal byproduct of marathons and ultramarathons and requires medical attention only if it persists, Fieseler says. Nonsteroidal anti-inflammatory drugs like aspirin and ibuprofen can also cause similar symptoms.
Current Opinion in Clinical Nutrition and Metabolic Care: Your bowels are creatures of habit, whether from a natural cycle or a morning cup of coffee. When routines change, the consequences can be dire, as American marathon record-holder Deena Kastor learned at the 2009 Chicago Marathon. That morning, her body was still on West Coast time. Coming off a day of "grazing on carbohydrates," the urge to use the bathroom didn't strike--until midway through the race. One port-a-potty stop later, Kastor was well behind the leaders.
"I would suggest getting up earlier so there is time to get in a good meal and use the bathroom," she says. "It's difficult to get up at 4 a.m., but it will ensure a more comfortable race." Many runners find that a short shakeout run several hours before a race provides the stimulus to get their systems moving.
One thing all runners should avoid is introducing new foods and beverages into the diet on race day. Scordino says having a large bowl of wheat cereal for lunch the day of the 10,000m--and all the insoluble fiber that came with it--sent her bowels over the edge. If you'll be taking fluids or gels during a race, practice with them beforehand to make sure you tolerate them.
Stay hydrated: Sweating away more than 4 percent of your body weight greatly increases the risk you'll experience diarrhea while running. Not coincidentally, the incidence of runner's trots is often highest at the end of a long run. Diarrhea has extremely high water content, making it a cause of dehydration. Be sure to take in fluids before, during and after exercising.
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Runners with bouts of lower GI distress often turn to medication and invasive procedures to remain accident-free on the run. Of these, the safest course is a dose of anti-diarrheal medication like Imodium or Kaopectate. "If you're not getting bloody diarrhea, your diet shows no triggers and it doesn't happen [except during intense or long runs], then I think it's OK to prophylax with Imodium," Fieseler says.
On the other end of the spectrum are runners who purge their intestines with chemical laxatives, enemas, bowel preps and colonic irrigations. These can alter your electrolyte levels and have major side effects, including nausea and stomach cramping. "The more aggressive the bowel program, the greater the possibility you'll have electrolyte abnormalities," Fieseler says. "I think you're dancing with the devil."
IT HAPPENS
Two days after the 10,000m, Scordino toed the line in the 5,000m. Back on her usual eating routine (no wheat cereal), she placed sixth again, but this time she was able to linger on the track and congratulate the other runners.
"A lot of people were saying, 'You can't go into this race thinking it's going to happen again,' " she says. "I'm somebody who doesn't let that affect my race. If it happens again, well, all right, it happened before."
