Exercise-Induced Bronchoconstriction in Cyclists: A Cross-Sectional Study in Saudi Arabia

Background: EIB presents a significant challenge for athletes and recreational exercisers, affecting health and performance. Despite the popularity of cycling as an aerobic activity, the link between EIB and cyclists remains poorly understood. Objective: To assess the EIB among cyclists in Jeddah, KSA. Methods: In this cross-sectional study, self-volunteered participants from Jeddah cyclist groups were categorized into beginner, intermediate, and advanced levels based on experience and endurance. Laboratory at room temperature. The exercise challenge involved a rapid increase in exercise intensity over approximately 2-5 min to achieve a speed of 30 km/h or above, sustained for at least 5-6 min to achieve a heart rate of 80-90% of the predicted maximum. Pulmonary function tests were conducted at baseline, 15 min, and 30 min post-exercise, following ATS/ERS guidelines. A fall in FEV1 of ≥ 10% was considered positive for EIB. The study was immediately halted if participants experienced respiratory difficulties, and emergency measures, including short-acting beta2-agonists and oxygen therapy, were administered. Results: A total of 56 participants were enrolled, with 30% classified as beginners and 35% each as intermediate and advanced-level cyclists. Among the participants, 56% were male and 44% were female. The average baseline spirometry of the participants was 83.4 ± 0.40% of the predicted value. The results revealed no significant changes in FEV1, FEV1/forced vital capacity (FVC) ratio, and mid-expiratory flow among intermediate to advanced-level cyclists. However, there was a transient reduction in spirometry values immediately post 15 min, which was statistically insignificant. Interestingly, beginners exhibited a notable 12% reduction in FEV1 immediately post 15 min exercise (baseline 3.99 ± 0.91 to 3.72 ± 0.97, a P-value of .003). However, spirometry values returned to normal levels at 30 min post-exercise. This suggests a temporary impact of exercise on lung function among novice cyclists, potentially indicative of EIB. Conclusions: We found there is no exercise-induced bronchoconstriction among intermediate to advanced level cyclists. However, beginners reported a reduction in FEV1 at 15 min, which was relieved subsequently. Further research is essential to elucidate the mechanisms and risk factors associated with EIB in cyclists.