Event medicine: injury and illness during an expedition-length adventure race.

To describe the incidence and type of injury and illness occurring during an expedition-length adventure race and identify those resulting in withdrawal from the event, a prospective cohort study was conducted of the injuries and illness treated during the Subaru Primal Quest Expedition Adventure Race trade mark held in Colorado July 7-16, 2002. All racers, support crewmembers, and race staff were eligible to participate in the study. When a member of the study group received medical care due to an injury or illness, the encounter was recorded on a Medical Encounter Form.