Exercise Tolerance Test or
Exercise for Desaturation Test

The exercise tolerance test evaluates the ability of your heart and lungs to provide oxygen and remove carbon dioxide from the bloodstream before, during and after you exercise.

The exercise for desaturation test evaluates your oxygen needs at rest and during exercise.


Preparing for the Test

  • Continue to take all of your medicine as you usually do.

  • Exercising can drop blood sugar in patients who are taking medications to control diabetes. Bring your glucose meter, test strips, and a source of fast-acting glucose with you (such as glucose tablets or glucose gel).

  • Eat a light meal 2 hours before the test.

  • Wear comfortable clothes for exercise. No dresses, please. Wear tennis (running) type shoes. Avoid wearing sandals, slippers or high heels.


During the Exercise Tests

A technician will explain what you need to do during the exercise test. Before the testing begins EKG electrodes will be placed on your chest to monitor you heart. Your blood pressure will be taken before, during and after you exercise. A pulse oximeter will be placed on your earlobe or fingertip to monitor your oxygen. If arterial blood gas samples will be taken while you exercise a catheter will be placed in an artery in your arm.


Exercise Tolerance Test

If you are doing the exercise tolerance test, you will be asked to ride a stationary bicycle. You will be monitored before, during and after you exercise. An exercise physiologist will be present while you exercise.


Exercise for Desaturation Test

If you are doing the exercise for desaturation test, you will be asked to walk on a treadmill at a comfortable pace for a maximum of 6 minutes per exercise period. Multiple 6 minute walking exercise periods may be required. You may be asked to wear oxygen during the testing periods.

  • EKG leads are placed to monitor the heart during exercise.
  • Exercise Equipment
  • Patient exercising while being monitored.


Length of the Test

The Exercise Tolerance test often takes 2 hours. The Exercise for Desaturation test often takes 1½ hour. Actual exercise time does not take 2 hours. Some of the test period is to prepare you for the test and observe you after the test.


Day of the Test

On the day of your scheduled test, report to room A310a at Pulmonary Physiology Services, (PPS), located on the 3rd floor of the May building. If you have questions please call Pulmonary Physiology Services at 303.398.1530.

Get directions to and view a campus map of National Jewish Health.


This information has been approved by Amy Olson, MD, MSPH and George Zeman RRT, CPFT, BS (June 2014).