“Runner’s Trots” or Stop the Leak

You are a competitive athlete. You put a lot of hard work into your training days in, days out, completing every workout as prescribed. You are the workhorse, doing everything necessary to succeed in the sport you are in. You pay close attention to your nutrition and your kitchen has no place for Doritos and donuts. You fuel your machinery with high octane, nutritiously rich foods. While your friends are just getting ready to hit the bars on Friday night, you are in your bed at 8 pm. You sacrifice meeting with your buddies, because you know how important the quality sleep is for recovery. Everything seem to be in check and there is nothing that could possibly stop you on your way to your dream – a podium.
Nothing besides… diarrhea.

Discussing intestinal problems in athletes is not sexy. What’s even less sexy is shitting yourself on the course in front of other people and fellow athletes.

You are not alone

Gastrointestinal problems among athletes are more common than you may think. About 30 to 50% of endurance athletes experience GI problems related to exercise. The numbers go higher with the level of athlete and can reach 70% for elite class performers.

Don’t perceive GI problems as your personal flaw. Instead accept it as the opportunity to learn and grow. Your body is intelligent super-machine and it is trying to communicate with you by bringing up GI symptoms, which only cover the bigger underlying issues. Work with your body, not agains it. Understand that there is not a singe person in the world that will have exact same body as yours. People keep different lifestyles, eat different foods and have personal training regimens. It is nearly impossible to create universal “pill” that will help each and everyone. You must take initiative in your hands and experiment to find the root cause of your GI distress. Realize that you are the one who caused your body behave this way, and you are the one responsible to fix it. However you are not alone and I am here to help you and give you some tips on how to fix what’s leaking.

What causes GI distress?

There are many reasons why your tummy fail on you. We can place them into 3 buckets: mechanical, physiological and nutritional. Let’s break them down:


  • The mechanical causes of GI-problems are either impact-related or are related to posture. Running and jumping movements cause your GI track repetitively bounce, which can contribute to lower GI symptoms such as diarrhea and urgency. More severe case of lower GI issues is gastrointestinal bleeding and is common amongst long distance runners.
  • Posture of your body also have an effect on GI symptoms. Shifting to aero position on a bicycle move your body to more horizontal position and increase pressure on the abdomen, which can trigger upper GI symptoms.

“The frequency is almost twice as high during running than during other endurance sports as cycling or swimming and 1.5-3.0 times higher in the elite athletes than the recreational exercisers“, (Erick Prado de Oliveira, Oct 2009).


  • Reduced blood flow and pre-competition anxiety fall under physiological causes of GI-symptoms. During exercise blood flow to the gut can be reduced by as much as 80%. The body redirect blood to the working muscles and compromise gut function to varying degrees.
  • Anxiety and stress mess up your hormone secretion which affects gut movement, compromise absorption rate and cause loose stool.


  • Fiber, fat, protein, and fructose intake increase the risk of developing GI-symptoms. Dehydration with body weight loss greater than 4% may also exacerbate the symptoms.
  • Dehydration. In an extensive literature review using an evidence-based approach, main factor for exercise-induced GI tract symptoms is shown to be dehydration (body weight loss > 4% during or after exercise).
  • Hydration solutions overloaded with carbs can also distress your stomach. Too much is >12 g /100 ml of carbohydrate as well as electrolytes (most sports drinks are around ~6 g/100 ml).

Association was reported between nutritional practices and GI complaints during a half ironman-distance triathlon with the intake of fiber, fat, protein and concentrated carbohydrate solutions during the triathlon, in particular beverages with very high osmolarity“, (Erick Prado de Oliveira, Sep 28, 2011).

Alright, let’s get practical…

Foods to Avoid before exercise

  • High fibre foods. (use the table below to learn about fiber content of some of the most common foods you need to stay away from)
  • Fermented foods. Wanna know where adrenaline is coming from? Have Kombucha as a pre-workout.
  • Coffee and tea. Hot fluids can stimulate gut movements while caffeine itself can have a laxative effect
  • Fatty and Spicy foods
  • Alcohol
  • Vitamin C in large doses

Are you Overtraining?

Below are the few possible underlying causes of runner’s diarrhea and other intestinal problems which are less obvious than the ones I described above and require your personal assessment.

Let’s dig deeper…

Food digestion is very energy-demanding process and requires your body to dedicate energy resources into it. When you overload your body and it can’t handle the external stress caused by training, it puts less priority on eating and digestion.

When the off-season is over, athletes are usually ramping up volume, intensity and frequency of their workouts. Total load on the body increases, while caloric consumption often stays the same. In addition, the amount of rest and downtime is not properly adjusted to support higher training load. This essentially leads to overtraining.

Overtraining can disrupt your liver’s ability to properly break down nutrients, which can lead to leaky gut syndrome, bouts of diarrhea or constipation.

You haven’t always had GI problems, however at one point in time something worked as a trigger and you started to experience them. Next time you find yourself on a toilet after another “incident”, ask yourself the following questions to narrow down the possible causes:

  • Do you remember when you began having the symptoms?
  • Did your training regimen change lately?
  • Do you experience any of the signs of overtraining?
    • Washed-out feelings (tired, drained, lack of energy)
    • Night sweats
    • Mild leg soreness, general aches, and pains
    • Pain in muscles and joints
    • Drop in performance (decrease in training capacity/intensity)
    • Insomnia
    • Decreased immunity (increased number of colds, and sore throats)
    • Moodiness, irritability, depression, loss of enthusiasm for the sport
    • Decreased appetite
  • Is your caloric consumption adequate to the level of energy you expand? What those calories are mainly coming from (carbs, fat or protein)?
  • Have you introduced any new sports supplements into your diet?

When all else fails

There is no quick fix for your health issues and there is no magic pill that will cure you once and forever. You must search for the answers by asking yourself the questions outlined above, you need to experiment with different foods, especially during pre-workout time period.
However racing season is here and you need something that could at least relieve the symptoms while you search for the root cause. Below is the over counter medicine that might temporarily stop the leakage:

Pepermint TUMS

Taking peppermint TUMS prior to hard efforts to decrease stomach irritation and diarrhea
Here’s how TUMS may help with your symptoms:
Calcium works with the neuromuscular contractions and muscle metabolism
Carbonate helps to coat the intestinal cells, reducing endotoxin release and the ensuing symptoms
Peppermint is a homeopathic remedy for GI disturbances.


Imodium help stop diarrhea by slowing the movement of food through your intestines. Many runners suggest that by taking a does prior to long runs or races could relieve GI problems. It can also take up to 48 hours to work, so if you’re trying it for the first time on race day there are no guarantees.

Possible side effects of Imodium include:
  • dizziness,
  • drowsiness,
  • tiredness,
  • constipation,
  • stomach pain,
  • skin rash, or itching.

Again, it should be considered as an option… not a solution. Figure out the cause, don’t mask it.


Lomotil (diphenoxylate and atropine) is alternative medicine to imodium and both are antidiarrheal medications used to treat diarrhea.

Common side effects of Lomotil include:

  • drowsiness,
  • dizziness,
  • headache,
  • tiredness,
  • restlessness,
  • blurred vision,
  • dry mouth,
  • nausea,
  • vomiting,
  • upset stomach,
  • loss of appetite,
  • skin rash, or


Super Starch” mixes are used by many endurance athletes to fuel their workouts. Unlike sports gels and high GI sugary solutions offered on the course, super starch mixes don’t overload the system with a high GI sugar shock, which may prevent some gastro intestinal problems. If you tried eating real food of all kinds, various different gels (including all natural ones) and still have GI issues, you might want to try super starch mixes.


  • GI problems should not be perceived as personal flaw. Instead they should be used as the opportunity to learn and grow.
  • Mechanics, physiology and inadequate nutrition are main contributors to GI distress.
  • Reducing consumption or avoiding certain foods prior to exercise can help reduce or eliminate symptoms.
  • Overtraining can be the root cause of gastrointestinal problems.
  • There are over counter medications that can help reduce GI distress symptoms.


  1. How much fiber is found in common foods? (2018, November 17). Retrieved April 3, 2019, from https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/high-fiber-foods/art-20050948
  2. Clark, N. (2012). Recognizing and managing exercise-associated diarrhea. ACSM’s Health and Fitness Journal, 16(3): 22-26.
  3. Masters Athlete. (2012, November 30). Retrieved April 4, 2019, from http://www.mastersathlete.com.au/2012/11/diarrhea-in-athletes-stopping-the-runs/
  4. Lomotil vs. Imodium Treatment for Diarrhea: Differences & Side Effects. (n.d.). Retrieved April 4, 2019, from https://www.rxlist.com/lomotil_vs_imodium/drugs-condition.htm
  5. Oliveira, E., De. (2009, September). The impact of physical exercise on the gastrointestinal tract. [Scholarly project]. Retrieved April 5, 2019, from https://www.ncbi.nlm.nih.gov/pubmed/19535976
  6. De Oliveira, E. P., & Burini, R. C. (2011, September 28). Food-dependent, exercise-induced gastrointestinal distress. Retrieved April 5, 2019, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3190328/