Objectives:
* To assess the effect of breathing retraining on asthma-related health status, asthma control and objective indices of asthma severity (bronchial hyper-reactivity (BHR), sputum eosinophilia and nitric oxide production) in patients with symptomatic asthma.
* To compare the relationship between symptoms of dysfunctional breathing (Nijmegen Questionnaire screening score), changes in asthma-related health status and other parameters resulting from breathing retraining
* To explore the relationship between dysfunctional breathing, baseline asthma symptoms, treatment and asthma-related quality of life.
* To estimate the cost effectiveness of the breathing retraining intervention
