GASTROINTESTINAL-BLEEDING DURING AN ULTRAMARATHON

Digestive symptoms and gastrointestinal bleeding occur in endurance runners and may contribute to runner's anemia. The cause is unknown, but the frequency of fecal blood loss has been reported to be 8-23% of marathon runners (1-7). Races of longer distances have not been investigated. An ultramarathon is a race that is longer than the 26.2 miles of a marathon and commonly involves distances of 30-100 or more miles and can last 24 hr or more. It differs from the marathon in duration, pace, and intrarace diet. The Old Dominion One Hundred Mile Endurance Run is held in the mountains of Virginia each June. It is open only to experienced ultrarunners who have completed a 50-mile race in less than 9 hr. This race offers a unique opportunity to study highly trained individuals undergoing a tremendous stress to not only their cardiovascular and musculoskeletal systems but also to their gastrointestinal system. The purpose of this prospective study is to determine the incidence of Hemoccult positivity occurring in association with an ultramarathon and evaluating, by means of a questionnaire, cofactors contributing to the gastrointestinal bleeding. © 1990 Plenum Publishing Corporation.