Dear editor,Marathon running is a strenuous activity that places stress on the gastrointestinal system.~([1])In fact,30% to 81% of runners report gastrointestinal complaints,which include bloating,abdominal cramps,rectal incontinence,and gastrointestinal bleeding.~([1-3])Exercise-induced ischemic colitis represents an extreme but rare manifestation of gastrointestinal pathology Dear editor, Marathon running is a strenuous activity that places stress on the gastrointestinal system. ~ ([1]) In fact, 30% to 81% of runners report gastrointestinal complaints, which include bloating, abdominal cramps, rectal incontinence, and gastrointestinal bleeding . ~ ([1-3]) Exercise-induced ischemic colitis represents an extreme but rare manifestation of gastrointestinal pathology