Occult Gastrointestinal Bleeding in Endurance Cyclists.

In brief Gastrointestinal (GI) bleeding has been well documented in long-distance runners but not in cyclists. The disorder is thought to occur in other strenuous endurance sports as well. The purpose of the present study was to identify the incidence of occult GI bleeding in a large group of endurance cyclists who participated in the 7-day Bike Ride Across Nebraska. Of 500 participants, 35 submitted 163 stool specimens during the first 6 days of the ride; only two specimens, from two riders (1.2%), were positive for occult blood. GI bleeding deserves further research to determine the incidence and cause or causes of this intriguing problem among athletes who engage in strenuous sports.