Screening of exercise-induced bronchoconstriction in skiers and biathlonists at different periods of annual training cycle

Abstract

Summary. The purpose of the study was to investigate prevalence of exercise-induced bronchoconstriction (EIB) in winter sports athletes at different periods of an annual training cycle and to evaluate a role of NO production in the respiratory tract for EIB occurrence. 92 athletes were examined during a precompetitive period and 78 were examined during a competitive period of an annual training cycle (mean age was 17.5 ± 2.3 years). EIB was detected using an indirect exercise field-test in cold air. Before and after the challenge test the fractional exhaled NO (FeNO) was measured. Postexercise FEV1 decreased ≥ 10 % in 6.4 % and 6.5 % of athletes during the competitive and the precompetitive periods, respectively. A correlation was found between ΔFEV1 and ΔFEF25–75. In EIB-positive athletes, there was a significantly lower baseline FeNO during the precompetitive period (p = 0.03). Relationships were determined between post-exercise FEV1, FVC, PEF, FEF25–75 and post-exercise FeNO. The EIB prevalence among skiers and biathletes was as low as 6.5 %. The NO level correlated with pulmonary function in elite athletes.