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Runners’ trots

published: 01-20-2012 Journal entry icon

There’s a phenomenon runners sometimes experience that’s commonly called “runners’ trots” – otherwise known as diarrhea – that has risk factors and that can possibly be avoided. Although the “trots” usually don’t last long and are generally nothing to worry about, they certainly can be a major annoyance, causing lost time in training or competition and even embarrassment if there is literally “nowhere to go.”

The most common risk factors cited are for those who are young, female, susceptible to irritable bowel syndrome, or lactose intolerant, as well as those who have had a previous abdominal surgery. The things we do to our bodies that reportedly increase risk are high-intensity exercise, dehydration, vertical-impact sports (e.g., running vs. biking), poor conditioning, medication, and diet. Although these are stated in the medical literature as risk factors, a recent study published in the International Sportmed Journal examined the evidence behind each of these risks to see if they hold up under scrutiny – and there’s surprisingly little evidence to support many of the statements about risk factors for developing “runners’ trots.” Most of the evidence was limited and relied on either single studies or multiple studies with varying results but a tendency toward supporting the conclusion.

Here are the conclusions of this evidence-based study:

The only strongly supported evidence was for dehydration to increase the risk of diarrhea. Female gender, younger age, high-intensity training, vertical impact, and medication had limited support and could go either way. Finally irritable bowel, lactose intolerance, previous abdominal surgery, poor conditioning, and dietary factors had very weak support. Keep in mind that little or no evidence does not make something true or false; it just means we have insufficient scientific evidence for any assumption.

So, based on the studies, how can you avoid “runners’ trots?”

  1. The evidence certainly supports staying well hydrated so that the bowel gets an adequate blood supply.

Even though the evidence for doing some things is not strong, they make sense and are not harmful. These include:

  1. Avoid a large meal 3-6 hours prior to running.
  2. Avoid food or drinks that have non-absorbable sweeteners (such as sorbital or sucralose), caffeine, and/or a high fat content.
  3. Don’t ingest concentrated carbohydrates (high glycemic index) before running.
  4. Be aware that energy bars and gels may contribute to the “trots” for some people.
  5. Avoid taking anti-diarrheal medications such as loperamide (e.g., Imodium) or Lomotil, since they can affect the ability of the body to tolerate heat.
  6. Wear loose-fitting clothing to reduce irritation.
  7. If symptoms persist for more than a few days, seek medical attention to be sure there is not an underlying cause.

    Enjoy your run!