Inhaled salbutamol does not affect athletic performance in asthmatic and non-asthmatic cyclists

Rationale Salbutamol may affect lung function and exercise performance differently in individuals with and without asthma. Objectives To compare the effects of inhaled salbutamol on lung function, exercise performance and respiratory parameters during cycling exercise in athletes with a positive response to a eucapnic voluntary hyperpnoea (EVH+) and negative (EVH−) challenge, indicative of exercise-induced bronchoconstriction. Methods In a randomised controlled trial with a crossover design, a total of 49 well-trained male athletes (14 EVH+ and 35 EVH−) performed two simulated 10 km time-trials on a cycle ergometer 60 min after the inhalation of either 400 μg of salbutamol or a placebo. Lung function, assessed by forced expiratory volume in 1 s, was measured immediately before and 30 min after inhalation. Performance was measured by mean power output. Measurements & main results Despite a significant increase in lung function after the inhalation of salbutamol compared to the placebo (p0.05) or leg exertion (p>0.05) during exercise. Salbutamol did not affect mean power output: EVH+ and EVH− athletes averaged 4.0 (0.5) and 4.1 (0.5) W/kg after salbutamol and 4.0 (0.5) W/kg and 4.0 (0.4) W/kg after placebo, respectively (p>0.05 for each comparison). Conclusions The inhalation of salbutamol induced a significant increase in resting lung function in EVH+ and EVH− athletes but this improvement in lung function did not translate to improved exercise performance. Salbutamol had no discernible effect on key ventilatory and exercise parameters regardless of EVH challenge outcome.