Exercise has a paradoxical relationship to asthma. It has been known for nearly 2000 years that exercise can provoke bronchoconstriction,1 termed exercise-induced bronchoconstriction or exercise-induced asthma. Yet exercise has also been prescribed to assist in the management of asthma as long ago as the middle of the 16th century.2 Over the last two decades, evidence has been accumulating that intense repeated exercise can injure airways and promote the development of airway hyperresponsiveness (AHR) and/or asthma in athletes with no past or family history of asthma.3 This issue of BJSM will focus on the third aspect of this triad.

Concerned that Olympic athletes may have been misusing inhaled β₂ agonists (IBA), in 2002 the International Olympic Committee (IOC) introduced the requirement that athletes had to demonstrate current asthma/AHR to use IBA before an event at the Olympic Games.4 It is stressed that this policy was introduced to protect the health of athletes and was not an antidoping measure. These requirements continued for four games and applications were managed by an IOC Independent Asthma Panel.5 After Beijing 2008, the World AntiDoping Agency (WADA) followed the IOC's lead by introducing similar requirements for athletes globally in …