You bought new shoes, ramped up your training and worked on your hydration. As it approaches race day, one question remains: Did you train your gut?

Surveys of marathon or distance runners indicate that approximately 25% of athletes experience some form of gastrointestinal (GI) distress during the race. Why are runners more prone to digestive problems?

Running, particularly long distances, directs blood flow away from the gut to meet the demands of running and to help rid the body of heat. Additionally, the butterflies you feel at the beginning of the race are caused by stress hormones that can also influence the rate of stomach emptying.

While part of the reason your stomach may not cooperate is the inherent physical demand of running, you can still minimize the gastric distress that can threaten race day by following these rules:

  • Hydrate - Blood flow will be directed away from your gut and dehydration can reduce blood volume further. Adequate fluids early in the race can expand blood volume and maximize your GI hydration needs.
  • Fiber: Friend or foe? - Fiber, although healthy for day to day consumption, can be irritating to some athletes. Water insoluble fiber found in wheat bran for example can stimulate the gut to empty faster than you would like. Try choosing lower fiber foods, such as rice or pasta instead of 100% whole wheat breads.
  • Discover hidden gut enemies - Artificial sweeteners ending in “ol” can cause osmotic diarrhea. They are found in sugarless gums and candies and cause gas cramping or diarrhea. Caffeine during these gut stressful times can also cause diarrhea so moderate your consumption.
  • Train with race day foods - As you amp up your miles, practice eating your race day meals. Good race day foods include those high in carbohydrate and moderate in protein and fat, such as oatmeal, a banana and scrambled eggs or egg whites. However, the key on race day is to eat the same foods you have been eating during your training runs. It is never a good idea to introduce a new food on the day of the big race.

Time, preparation and practice will help your avoid these common training pitfalls.

Ready to Take Your Performance to the Next Level?

To schedule an appointment for one of our Human Performance tests, please call (713) 897-7912 or click the link below to learn more about our Human Performance Services.

Learn More

Contact Us

For more information on the Rockets Sports Medicine Institute orthopedic doctors or surgeons, treatment for injuries, scheduling Human Performance services, or getting more information about physical therapy, please fill out the form below or call us at (713) 222-2273


Thank you for contacting the Memorial Hermann | Rockets Sports Medicine Institute. We have received your inquiry, and a team member will contact you soon.

If you need more immediate assistance, please call us at (713) 222-2273.

If you are experiencing a medical emergency, call 911 or go to the nearest emergency room.

Sports Nutrition
Orthopedics and Sports Medicine Rockets Sports Medicine Institute Physical Therapy Human Performance Sports Nutrition Services