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Prevent – and stop – common GI problems on the run

Prevent - and stop - common GI problems on the run

Are you one of those runners who carefully plans out their routes based on where the bathrooms are located? If so, you’re not alone.

About 65 percent of runners suffer from mid-run stomach problems at some point during their running careers. Not only are runner’s trots and other gastrointestinal (GI) issues embarrassing and bothersome, but they can hinder race performance and lead to dehydration. Severe runner’s diarrhea can even cause weight loss and vitamin and mineral deficiencies.

Why stomach issues strike runners

Runners often complain of the following stomach issues during or soon after a run: diarrhea, nausea, vomiting, bloating, side stitches, or gastroesophageal reflux.

While these issues are common among runners, experts aren’t sure exactly why they happen, however, they have a few theories. Running may do the following to your digestive tract:

  • Decrease blood flow to the stomach. On a run, your legs work hard. So extra blood flows away from the stomach and goes towards the legs so they can keep moving. This lack of blood flow can cause the stomach to feel off-balanced, and issues can occur.
  • Alter the digestion process. Running may cause the digestive process to speed up or slow down. This can result in diarrhea or other discomforts.
  • Shake things up. The jarring motion of running literally shakes up the digestive tract, which can bring on nausea, vomiting, and other problems.

What you can do to prevent GI issues

You can prevent runner’s trots and other unpleasantries by:

  • Paying attention to your diet. Artificial sweeteners, caffeine, dairy products, high-fiber foods, and high-fat foods may trigger runner’s diarrhea in some people. However, finding out what’s causing your stomach issues will be a matter of trial and error. Limit a suspected trigger for the few days leading up to a run and see how you feel during the run. If your stomach problems go away, you’ll know to stay away from that food. Once you’ve identified safe foods, only eat those during training and before races.
  • Wear loose-fitting, comfortable clothing. Clothes that fit tightly around your midsection can aggravate symptoms.
  • Keep well-hydrated. Dehydration slows your body’s ability to digest food, so not drinking enough water can set you up for problems.
  • Check the weather. Runner’s trots are more likely to happen when the mercury is high, so hit the treadmill if the outside temperature is too hot.

What you can do to help GI issues mid-race

If you’re in the middle of a run and start having GI problems, these quick-fixes may help:

  • Slow down. Running too fast may cause nausea — slowing down may ease these symptoms.
  • Take deep breaths. Shallow breathing is linked with stomach cramps and side stitches. Breathing deeply from your diaphragm can correct these problems.
  • Cut the run short. Runner’s trots are most common in distance runners, so stick with shorter distances until your stomach issues get better.
  • Mind your fuel. Over-doing mid-run fuel can worsen GI problems. Be mindful to only take in what you need.
  • Find a bathroom. When all else fails, a quick bathroom stop may be enough to make you feel better. Next time, take action to prevent stomach problems before they start.

Written by Jenilee Matz, MPH. Jen is writer, runner, and new(ish) mom living in the suburbs of Charlotte, N.C.

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