What is exercise induced asthma?

Nearly all asthmatics experience bronchospasm after exercise, 70-80% show decreased PF and FEV1 after 6 minute exercise challenge, during exercise they seem protected due to bronchodilation mechanism by catecholamines. Cough and SoB parallel to decreased LF, symptoms abate without treatment, but can return immediately to normal function after admin of b-agonist. Risk factors: poor control os asthma, exercise in cold (mast cell producing mediators), greater exercise intensity, bronchoconstriction is less in a second challenge after a first one in an hour, so warmup is helpful Pretreatment can reduce it 90% (by b-agonist)