How It Is Done
An exercise electrocardiogram (EKG or ECG) is usually done in a doctor's office, clinic, or hospital lab by a health professional or doctor. The test results are evaluated by an internist, family medicine doctor, or cardiologist.
Before the test
- Areas on your arms, legs, and chest where small pads or patches (electrodes) will be placed are cleaned and may be shaved to provide a clean, smooth surface to attach the electrodes.
- The electrodes are hooked to a machine that traces your heart activity onto a piece of paper. Your chest may be loosely wrapped with an elastic band to keep the electrodes from falling off during exercise. A blood pressure cuff will be wrapped around your upper arm so that your blood pressure can be checked every few minutes during the test.
During the test
For exercise, you typically either walk on a treadmill or pedal on a stationary bicycle while being monitored by an EKG machine. Your EKG will be monitored on screen, and paper copies will be printed out for later review before you start the exercise, at the end of each section of exercise, and while you are recovering.
The test is usually performed in a series of stages, each lasting 3 minutes. After each 3-minute stage, the resistance or speed of the treadmill or bicycle is increased.
- For the treadmill test, the treadmill will move slowly in a level or slightly inclined position. As the test progresses, the speed and steepness of the treadmill will be increased so that you will be walking faster and at a greater incline.
- For the stationary bicycle, you will sit on the bicycle with the seat and handlebars adjusted so that you can pedal comfortably. You can use the handlebars to help you balance, but you should not use them to support your weight. You will be asked to pedal fast enough to maintain a certain speed. The resistance will then be gradually increased, making it harder to pedal.
- In both the treadmill and the bicycle tests, your EKG, heart rate, and blood pressure will be recorded during the exercise. Your heart rate and EKG will be recorded continuously. Your blood pressure is usually measured during the second minute of each stage. It may be measured more frequently if the readings are too high or too low. During the test, you might be asked to give a number that answers the question "How hard do you feel the exercise is?" The number will be on a scale from 6 to 20 and is called a rating of perceived exertion.
- The test continues until you need to stop, until you reach your maximum heart rate, until you begin to show symptoms of stress on your heart and lungs (such as fatigue, extreme shortness of breath, or angina), or until the EKG tracing shows decreased blood flow to your heart muscle.
- The test may also be stopped if you develop serious irregular heartbeats or if your blood pressure drops below your resting level.
After the test