The aim of the study was to examine the physiological effect of endurance running on the asthmatic adult, an area in which there has been little research. The specific aims were to: firstly, examine the cardio-respiratory and metabolic responses to short term maximal and submaximal exercise of untrained asthmatics and non-asthmatics, and endurance-running-trained asthmatics; secondly, compare the physiological responses to prolonged endurance running of asthmatic and non-asthmatic athletes; thirdly, evaluate the effect of endurance running training on the previously untrained asthmatic.