The Runner’s Tummy

Experiencing physical activity by training to compete or exercising to improve our health are two ways to enhance quality of life. As you are going about your routine, stomach cramps can sometimes cause discomfort and cut short your workout. Runner’s tummy or gastrointestinal (GI) issues can hinder your ability to perform or achieve your activity goals. It can also be very embarrassing to the point where it can limit your desire to participate in sports, especially in adolescent years.

Gastrointestinal (GI) complaints are common among athletes with rates in the range of 30% to 70%. – JJ Waterman and R. Kupar 

While exercising, especially at high intensities, blood is redistributed to the muscles and less blood flows to the gut. The decrease in blood flow is known as ischemic colitis. Contributing factors can depend on the sport and the intensity exerted during the activity. Mechanical forces and neuroendocrine changes have also been shown to contribute to GI problems.

Gastrointestinal concerns vary from individual to individual and psychological stresses such as being nervous or anxious, which are more likely to occur on competition days, do not help the matter. Dehydration can also cause runner’s tummy especially in longer durations of exercise as opposed to short bouts. Foods high in fiber, fats and protein can increase the chances of GI symptoms especially if consumed 3 hours before competition or training. Lactose intolerance can also lead to GI sensitivity if lactose is ingested during high intensity exercise.

Minimizing GI issues:

• Keep track of foods and the symptoms to identify triggers. 
• Eat no less than three hours before your activity. 
• Avoid high fiber foods, fats and highly refined carbohydrates a day or two before competition. 
• The gut is trainable, so train for fluid intakes and adapt to intensity. 
• Manage stress on competition days. 

An array of things can cause runner’s tummy and pretesting your food and liquid intake can help minimize it. Overall, GI sensitivity depends on the individual and knowing your triggers is the best way to help you alleviate distress.

References Available from the SIRC Collection:

1. Deibert P, Koenig D, Dickhuth H, Berg A. The gastrointestinal system: The relationship between an athlete's health and sport performance. International Sportmed Journal. September 2005;6(3):130-140.

2. Guthrie C. Tame Your Ill-Tempered Tummy. Yoga Journal. September 2004;(183):42.

3. Simons S, Shaskan G. Gastrointestinal problems in distance running. International Sportmed Journal. September 2005;6(3):162-170.

4. Strid H, Simrén M. The effects of physical activity on the gastrointestinal tract. International Sportmed Journal. September 2005;6(3):151-161.

5. Uhes M, Sweet A, Cowles S. A BEHAVIORALLY ORIENTED STRESS REDUCTION PROGRAM AND ITS EFFECTS UPON SELF-REPORTED GASTRIC COMPLAINTS. Stress Medicine. January 1989;5(1):57-61.

6. Woodward G. The GI blues. Australian Orienteer. March 2013;(167):26-27.