This test tells how much air moves in and out of your lungs when you exercise. During the test, you may be asked to walk on a treadmill or ride on a stationary bike. The test may pinpoint where your breathing problems begin. They may begin in the lungs, the heart, or both. Your test results can also show a safe activity level for you.
Allow at least 30 minutes to check in. Prepare for the test as directed. You may be told to do any of the following:
Have a light breakfast no less than 2 hours before the test.
Stop eating and drinking fluids for 2 hours before the test. If you have diabetes, ask what you may eat or drink before the test.
Stop smoking for at least 8 to 12 hours before the test.
Stop taking certain medications before the test.
Do not exercise the morning before the test.
Wear comfortable exercise clothing and walking shoes, such as tennis shoes.
If you have dentures, wear them.
Small pads (electrodes) placed on your upper body will monitor your heart rate. A device clipped to your finger will measure the amount of oxygen in your blood. You will also wear nose clips and breathe through a mouthpiece:
Before you start to exercise, a spirometry test may be done. This will measure the amount of air you inhale and exhale while at rest.
While you exercise, your heart rate, breathing, and blood pressure are monitored. Exercise as long as you can. When the test is over, keep the mouthpiece in place until you are told to remove it.
Throughout the process, blood samples may be taken. This is done to measure oxygen and carbon dioxide in the blood during exercise.
You can return to your normal diet, activity, and medications. If you were told to skip medications before the test, ask if you should take them now. Your health care provider will discuss the test results with you at your next visit.
Like many tests, this test involves some risks. They may include:
Shortness of breath or wheezing
Rise or fall in blood pressure
Fainting, dizziness, or fatigue
Abnormal heartbeat or heart rate
Heart attack or stroke (rare)