Dietary FODMAP Manipulation for Exercise-Associated Gastrointestinal Symptoms: Why Symptom Severity Should Guide Our Approach

Exercise-induced gastrointestinal syndrome (EIGS) is a well-defined term that describes disruptions to gastrointestinal integrity and function that occur during exercise. A commonly reported outcome of EIGS is exercise-associated gastrointestinal symptoms (Ex-GIS), including flatulence, lower abdominal bloating and pain, and urge to defecate, which can compromise comfort, training quality and race-day execution. Low-fermentable oligo-, di-, mono-saccharide and polyol (FODMAP) diets are effective at reducing gastrointestinal symptoms in individuals with irritable bowel syndrome and, owing to similarities in symptom presentation, have increasingly been used by athletes to better manage Ex-GIS. This Current Opinion article argues that FODMAP manipulation should be used strategically rather than as a routine dietary default. For athletes with severe Ex-GIS, a short-term low-FODMAP approach may help attenuate symptoms around key training sessions and/or competition. In contrast, athletes with mild or infrequent symptoms may benefit from a more liberal FODMAP intake that mitigates disruptions to gastrointestinal integrity and potentially EIGS outcomes while avoiding unnecessary dietary restriction. However, neither approach has consistently been shown to improve performance. Accordingly, any modification of FODMAP intake should be individualized and guided by likely underlying primary mechanisms, symptom severity, exercise demands, and the need to maintain overall dietary adequacy.