 Cardiopulmonary exercise measurements are conducted in the consistent environment of the preassessment clinic in Clinic H, Freeman Hospital. CPX equipment includes an electronically braked cycle ergonometer, 12 lead ECG and a metabolic cart. The ECG allows online monitoring of all leads for rate and rhythm, and can measure changes in any S-T segment depressionelevation suggestive of cardiac ischaemia. The metabolic cart has oxygen and carbon dioxide analysers with a response time enabling breath-by-breath measurement. Calibration is ensured before each test. VO2, VCO2, heart rate, minute ventilation, and work rate are displayed continuously throughout the test. 