Exercise-Induced Bronchoconstriction in Athletes - Pathomechanism, Clinical Symptoms, and Current Methods of Treatment and Prevention

Introduction and objective: This article discusses the issue of exercise-induced bronchoconstriction (EIB), also known as exercise-induced asthma (EIA). The aim of this paper is to discuss current methods of diagnosis and treatment of EIB in athletes in light of current guidelines. Methodology: The ATS (American Thoracic Society) guidelines and available laboratory tests assessing bronchial hyperresponsiveness to indirect stimuli, such as exercise tests on a treadmill or cycle ergometer, eucapnic hyperventilation (EVH) and provocation tests using mannitol or hypertonic saline, and measurement of nitric oxide concentration in exhaled air (FENO). Results: It was established that the diagnosis of EIB requires a decrease in forced expiratory volume in 1 second (FEV) of at least 10% after physical exercise. The prevalence of the condition is estimated at 12–15% in the general population, between 10–20% in athletes competing in summer Olympic sports, and increasing to 50–70% in athletes competing in winter sports. The key mechanisms of post-exercise bronchoconstriction are the thermal and osmotic theories. Conclusions: Effective prevention of EIB includes both non-pharmacological methods and pharmacotherapy (primarily short- and long-acting beta2-mimetics, anti-leukotriene drugs). In patients with asthma, proper control of airway inflammation significantly reduces the severity of exercise-induced symptoms.