We plan to identify all Division I athletes, male and female, at the University of Arizona that are currently being treated for either EIB or asthma by review of preparticipation physical forms or identified by the medical staff. In addition, athletes that were prescribed inhalers through Campus Health Services will be identified through review of electronic pharmacy records. Each athlete identified will be matched with two control athletes (ie, not currently using asthma medications) from the same sport. Subjects will be tested for EIB using eucapnic voluntary hyperventilation, the gold standard for making this diagnosis.