Prevalence of Exercise-induced Bronchospasm among Nonasthmatic Cyclists: A Comparative Analysis across Skill Levels

rates in competitive cyclists have been reported as 59%, likely due to intense training loads and environmental stressors. 11Studies among recreational cyclists indicate lower prevalence rates of 20-23%. 12 IntroductIonExercise-induced bronchoconstriction (EIB) is characterized by a temporary and reversible constriction of the lower airways following intense physical exertion, affecting both asthmatic and nonasthmatic individuals. 1,2This condition involves the constriction of airway smooth muscles, mucosal edema, and inflammatory responses that lead to luminal narrowing, particularly in the smaller airways. 3,4EIB presents with symptoms such as cough, wheezing, dyspnea, chest tightness, and exercise intolerance, which can adversely affect athletic performance and participation in physical activities.High-intensity endurance activities, such as running and cycling, place significant ventilatory demands on individuals, predisposing them to airway dehydration and osmotic shifts in the bronchial mucosa. 5The pathophysiology of EIB involves the release of mast cell mediators and exercise-induced hyperventilation, resulting in respiratory water loss, increased airway osmolarity, and inflammatory cascades.These mechanisms may be exacerbated under extreme environmental conditions, including high temperatures, humidity, air pollution, or transitions between indoor and outdoor environments, factors pertinent to certain regions. 6ycling is a widely practiced aerobic activity that offers cardiometabolic and psychological benefits, including enhanced cardiorespiratory fitness and a reduced risk of chronic diseases. 7,8espite these advantages, the sustained high ventilatory loads during cycling may predispose athletes to airway dysfunction. 9Most epidemiological data on EIB are derived from European and North American cohorts of elite or highly trained athletes. 10Prevalence