Exercise-induced airway constriction.

J. E. COTES Breathlessness is one of a number of symptoms which may limit exercise; it usually does so when the ventilation during exercise approaches a maximal value which is determined by interaction between the drive to respiration and the mechanical properties of the lung. Assessment is based in the first instance on the clinical interview and simple measurements of lung function. Depending on the likely cause these may need to be supplemented by additional tests.