An exercise tolerance test can show abnormalities in the major blood vessels of the heart that do not happen when your heart is at rest or not under pressure.  It involves walking on a treadmill whilst continuous monitoring of your heart function and blood pressure are undertaken. Every three minutes the slope and speed of the treadmill will increase. Changes in the ECG may indicate the presence of coronary artery disease. The test takes 30 minutes and is performed by a doctor or cardiac nurse practitioner with a cardiac physiologist or cardiac nurse. Appointments for exercise tolerance test procedures are available at both Te Whatu Ora, Taranaki New Plymouth and Hāwera hospital sites.