Running out of breath

Abstract

There is emerging evidence that the prevalence of exercise-induced bronchospasm (EIB) is significantly under-reported in many sports. Little is known about the potential performance improvement that may exist when sports players are detected and treated for EIB, but optimal airway health is crucial for anyone undertaking regular exercise at any level. Athletes may not be aware of an underlying diagnosis of EIB, asthey may be asymptomatic, whilst other athletes may present with asthma-like symptoms but, upon testing, there is a negative test for EIB. The pathophysiology of bronchoconstriction that occurs in EIB differs from that which occurs in normal asthma, due to the large volumes of air that pass through the respiratory airways resulting in drying out of the aveolar fluid with resultant chemical release. A eucapnic voluntary hyperpnoea (EVH) challenge is the gold standard to detect underlying EIB when it results in a 10% drop from the baseline forced expiratory volume in one second (FEV1 ) in comparison to the baseline spirometric FEV1 . When a negative EVH challenge results, alternative respiratory diagnoses must be sought and treated. Hence not all exercise related breathing disorders encountered in family practice should be labelled as exercise induced asthma and treated as such.