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It’s one of the most embarrassing issues a runner can experience, yet everyone has been plagued by it at one point or another: You’re enjoying a run, or crushing a race, and just as you start really going for it…your stomach signals something’s not right. You can pinch, squeeze and hold all you want, but suddenly the gurgling, sharp, sudden pain takes over. You know if you don’t get to a bathroom stat there could be problems. Runner’s trots—damn you.
“I have been personally plagued by the notorious runner’s trots for all the years I have been a runner. Imagine being a gastroenterologist and feeling incapable of controlling your own intestinal tract!” shares Dr. Felice Schnoll-Sussman, Chief of Clinical Operations and Director of The Jay Monahan Center for Gastrointestinal Health at the NewYork-Presbyterian Hospital/Weill Cornell Medicine.
“Many people don’t report the problem, due to embarrassment, however studies have shown that as many as 20 to 50 percent of runners in a 10K race experience symptoms associated with runner’s trots,” says Dr. Schnoll-Sussman.
So what exactly is runner’s trots, or runner’s diarrhea? Dr. Schnoll-Sussman explains that it’s a range of gastrointestinal symptoms from nausea and painful cramping to flatulence and diarrhea. The urgent need for defecation may subsequently occur. They can be experienced during or after exercise.
People who run long distances can have several symptoms during competition and training. The longer the distance you run, the worse these symptoms could become. Some of these signs are:
- Belly cramps
- Fecal incontinence, or being unable to control bowel movements
- Chest pain
- Urge to poop
- Bloody stool
According to a 2019 article published in International Journal of Sport Nutrition and Exercise Metabolism, runner’s trots can also affect cyclists and swimmers. So, yay, at least we’re not alone?
What Causes Runner’s Trots?
While annoying and a little bit embarrassing, it’s important to know that runner’s trots are usually nothing to worry about. Experts say they’re a physiological phenomenon, not a disease.
There isn’t one clear reason why runner’s trots happen, although some things may raise your odds of it. Common factors include:
- The up and down motion of running, which can jostle the bowels
- Nonsteroidal anti-inflammatory drugs (NSAIDs) can increase likelihood of developing ischemic colitis
- The diversion of blood flow from the intestines to other muscles during a run
- Pre-race anxiety or general stress
- Nutrition (like high-fiber and high-fat foods, sweeteners, or caffeine)
The exact cause of runner’s trots is unknown, but the stress of long-distance running may bring out symptoms in people with underlying irritable bowel syndrome (IBS) or those with food intolerances such as issued caused by lactose. But the condition is certainly not limited to those with underlying issues.
As you start running, a number of different changes happen in your system. When your feet hit the pavement, vibrations roll through your body and jostle your intestines up and down. This likely contributes to a more rapid passage of fecal contents through them.
Gastrointestinal problems often happen because blood flow is reduced to those areas, and instead there’s an increase of blood flow that goes to the muscles you use to run. When you’re running, your body reduces the blood flow to non-essential areas (like your colon) in order to direct it where you need it more: your heart, lungs, legs, etc. But the lack of blood flow creates less oxygen and nutrients in your colon, which in turn can cause diarrhea.
How to Prevent Runner’s Trots
While there’s not a specific cause for runner’s trot, there are some precautions you can take before your long-distance runs and races.
There are many preventative tactics you can try to prevent runner’s trots so you can have your best race day, suggests Dr. Schnoll-Sussman:
- Limit the intake of high-fiber foods at least two days before a long race or training run. If you run a lot, try to pay attention to the amount of fiber you can eat without causing gas or upset stomach.
- Avoid or limit artificial sweeteners, dairy products, or any foods known to cause loose stools or flatulence for several days prior to a race or hard workout.
- Hydrate, hydrate, hydrate. Aim for a very light yellow urine color.
- Try to avoid eating at least two hours prior to exercise. This will allow for enough time for food to empty your stomach.
- If you do not need the caffeine stimulation, try to avoid the intake of caffeinated products and warm fluids close to race time.
- Know your race route. Plan out for restroom breaks if you develop the urgency while exercising. (Consider carrying toilet paper with you, just in case.)
- Practice your pre-day and morning of meal plans throughout training to see what works best for you.
- If you use gels during races, these may be the culprits. Practice different formulations to ensure that your stomach can tolerate the particular sugar each gel uses in its product.
- NEVER try something new (foods, gels, water supplements) on race day.
- Although one should not use these on a daily basis, for races or special events consider trying an over-the-counter antidiarrheal agent such as Imodium.
- Stress and pre-event jitters can contribute. Consider incorporating some relaxation techniques like slow deep breathing or mindfulness into your daily routine as well as during the pre-race period.
- Think about getting a consultation with a nutritionist who specializes in the care of athletes. They can carefully review your personal diet and make specific recommendations and modifications.
The most important thing is to know your body. “If you experience blood in your stool, weight loss, a change in appetite, recurrent nausea or vomiting, chronic changes in your bowel habits or ongoing abdominal pain, you should go to see your doctor,” expresses Dr. Schnoll-Sussman. “These symptoms may be a sign of something more serious and requires further investigation.”