ObjectiveThis study evaluates a sport-specific protocol to evaluate cross-country skiers for exercise-induced asthma (EIA).Study DesignParticipants completed an asthma symptom questionnaire prior to participation. They were then tested by portable digital spirometer with measurements prior to exercise and at 5-minute increments following a 15-minute cross-country skiing exercise session on a groomed ski trail.SettingAll spirometry measurements were collected indoors at Nordic ski areas in the Duluth, Minnesota, area. Each ski area was groomed for both skating and classical technique.Subjects99 high school skiers, 55 female and 44 male, of various skill levels were tested. All were members of their respective high school cross-country ski team. Testing was open to all ski team members. Skiers from seven different high schools participated.Main Outcome MeasuresBronchial hyperresponsiveness to exercise measured by the change in forced expiratory volume at 1 s (FEV1) following exercise. A result was considered positive if the decrement in FEV1 was greater than 10% in any two of the postexercise test increments in comparison with the preexercise baseline.Results28 of 99 (28%) skiers met the criteria for EIA. No significant differences were found with regards to gender, age, or previous experience. Several individual items on the Asthma Symptom Questionnaire were associated with a positive spirometry test.ConclusionsUsing a simple protocol of pre- and postexercise spirometry with a defined exercise challenge, a large number of athletes were screened objectively for this condition. Both the equipment and protocol worked well in the field environment and could easily be adapted to most any sports environment.