Introduction: Asthma is frequently reported in endurance athletes, particularly in cross-country skiers. It has been reported that an exercise field test performed with the competitive type of exercise is the better for diagnosing asthma and bronchial hyperresponsiveness in athletes than bronchial provocation with methacholine.
Objective: The main objective was to compare an exercise field test consisting of a skiing competition with methacholine bronchial provocation in the diagnosis of asthma and bronchial hyperresponsiveness among skiers.
Methods: Twenty-four elite cross-country skiers from the Norwegian national teams (males/females = 16/8) were included in the study. The cumulative dose of inhaled methacholine causing a 20% fall in forced expiratory volume in 1 s (FEV1) (PD20) was compared with reduction in lung function (FEV1) ≥ 10% from before to after an exercise field test consisting of a cross-country skiing competition, 10 km (males) and 7 km (females), respectively.
Results: Nine out of 24 (37.5%) athletes experienced a positive methacholine test (PD20 < 8 μmol) (2 females and 7 males), whereas only 2 of the 24 subjects (8.3%) had reductions in FEV1 ≥ 10% after the exercise field test. A significant negative correlation was found between age and bronchial responsiveness, r = −0.47, P = 0.02.
Conclusion: The methacholine bronchial provocation test is more sensitive than a sport specific exercise field test for identifying athletes with asthma and/or bronchial hyperresponsiveness.
1Norwegian School of Sport Sciences, Oslo, NORWAY; 2Medical Faculty, University of Bergen, Bergen, NORWAY; 3Stavanger University Hospital, Stavanger, NORWAY; 4Voksentoppen, Department of Paediatrics, Rikshospitalet-Radiumhospitalet Medical Center, Oslo, NORWAY; 5Faculty of Medicine, University of Oslo, Oslo, NORWAY; and 6Oslo Research Group for Asthma and Allergy in Childhood the Lung and Environment, Global European Allergy and Asthma Network, European Network of Centers of Excellence, Ghent, BELGIUM
Address for correspondence: Trine Stensrud, Norwegian School of Sport Sciences, PO Box 4014 Ullevaal Stadion, NO-0806 Oslo, Norway; E-mail: firstname.lastname@example.org.
Submitted for publication April 2007.
Accepted for publication May 2007.