The purpose of the present invention is to provide an ameliorating agent for exercise-induced gastrointestinal disorders, which can exert an ameliorating effect at a level that is the same as or higher than those achieved by the conventional techniques on exercise-induced gastrointestinal disorders including exercise-induced deterioration in intestinal barrier functions. The present invention relates to an ameliorating agent for exercise-induced gastrointestinal disorders, which contains cystine or a salt thereof as an active ingredient.
