A spectrum of lower gastrointestinal tract symptoms occurs in marathon runners. Although most symptoms are transient, reversible ischemic colitis is a rare complication that typically responds to supportive therapy. Because computed tomographic features have not been previously described to our knowledge, we describe abdominal computed tomographic manifestations of reversible ischemic colitis in three marathon runners. On computed tomography, reversible ischemic colitis involves the cecum, with varying involvement of the proximal colon.