Title: “Effects of inspired air in diagnosing exercise-induced bronchoconstriction in swimmers”
Supervisor: Dr. A William Sheel (Kinesiology)
Committee Members: Dr. Don McKenzie (Kinesiology), Dr. Michael Koehle (Kinesiology), James Brotherhood (UBC Athletics)
Abstract: Swimmers are known to have a high rates of exercise-induced bronchoconstriction (EIB). This is attributed to chronic inhalation of metabolites resting above the pool surface in indoor aquatic centres. The current ‘gold standard’ method in diagnosing EIB is the eucapnic voluntary hyperventilation (EVH) test, in which inspired air is cool and dry. Although this method is successful in detecting EIB, the EVH test has little application to swimmers where in aquatic conditions inspired air is typically warm, humid, and chlorinated. Additionally, the diagnosis of EIB requires a FEV1 fall index of ≥10% following provocation. Alternative methods such as, Slope-Ratio (SR) Index have been used in patients with COPD and asthmatics in detecting nonhomogeneous lung emptying, however not in patients with EIB. This study looks to compare three methods in provoking EIB in swimmers; the EVH test in a clinical setting, a modified EVH test in which inspired air is resting above pool water surface, and an exercise field test. This study also looks to use SR-Index in analyzing expired flow pre- and post-provocation as an additional method in monitoring changes in lung emptying. The study looks to recruit 30 high-level swimmers, to complete three days of testing. Each day subjects will complete baseline spirometry, followed by one of the three provocation methods. Following the provocation, the subject will complete post-test spirometry over the course of 20-minutes following the test. Developing an applied understanding of how EIB is provoked in swimmers can assist in diagnosing and managing the condition. Furthermore, if prevelance of EIB differs between the ‘gold standard’ method and chlorinated method, questions should be raised in how inhaled bronchodilators are prescribed to high level swimmers.