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Gastrointestinal disorders in athletes

John H Kwon, MD, PhD
J Thomas Lamont, MD
Section Editor
Lawrence S Friedman, MD
Deputy Editor
Shilpa Grover, MD, MPH, AGAF


Athletes are vulnerable to a variety of gastrointestinal disorders, some of which are related to physiologic changes resulting from exercise [1,2]. Physiologic changes include alterations in enteric nervous system activity, circulating gut hormone levels, intestinal blood flow, nutrient and electrolyte absorption, secretion and gut motility [1].

This topic review will discuss the most frequently observed gastrointestinal disorders that occur in athletes, focusing mainly on endurance athletes (table 1).


Most studies suggest that gastrointestinal (GI) problems are common among athletes, the incidence ranging from 20 to 96 percent [3-9]. The majority of endurance athletes experience GI symptoms during training or races; running appears to be more problematic than cycling. Among athletes competing in mixed endurance events (such as triathlons), the majority of symptoms occur during the running portion. The following illustrate the range of findings.

83 percent of participants in the 1986 Belfast City Marathon reported one or more GI disturbances during or immediately after running [3].

81 percent of athletes competing in the 1984 Dunedin Enduro multisport (swim, bicycle, canoe, and run) event experienced GI symptoms during training [4].


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Literature review current through: May 2017. | This topic last updated: Apr 30, 2015.
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