Study of Salbutamol Effects on Exercise and Breathing in Endurance Athletes Without Asthma

What this Trial Is About

Researchers are investigating the effects of beta-2 agonists, commonly used for asthma treatment, on exercise performance in non-asthmatic male and female endurance athletes. The study aims to determine if a specific group of non-asthmatic athletes who experience expiratory flow limitation EFL during intense exercise may benefit from these drugs. The study also explores whether female athletes experience greater benefits due to a higher prevalence of EFL. Participants will be randomly assigned to inhale either 400 g of salbutamol or a placebo via a metered-dose inhaler with a large-volume spacer before performing an incremental cardiopulmonary exercise test. Each inhalation is spaced by 60 seconds, with four inhalations total. The study uses a triple-blind design to assess the effects of salbutamol compared to placebo on exercise duration and breathing function. During the study, participants will undergo exercise tests where their time to exhaustion and breathing limitations will be measured. Researchers will also evaluate differences between sexes, ventilatory responses, and sensations of breathlessness after inhalation. The primary outcomes focus on time to exhaustion with salbutamol versus placebo, with secondary outcomes exploring effects on EFL and dyspnea. Participation lasts up to two weeks, including testing and monitoring periods.

Effects of Salbutamol in Athletes and Implications for Screening and Sports