What is a Continuous Laryngoscopy during Exercise test?
A Continuous Laryngoscopy during Exercise test (CLE) evaluates the function of the upper airway during high intensity exercise. Metabolic data is also collected to evaluate the ability of the heart and lungs to provide oxygen and remove carbon dioxide from the bloodstream before, during and after exercise.
How do you get ready for the test?
- Continue to take all of your medications as you usually do.
- Since exercising can drop blood sugar in patients who are taking medications to control diabetes, if you are diabetic, bring your glucose meter, test strips, and a source of fast·acting glucose with you (such as glucose tablets or glucose gel).
- Please eat as you normally would before exercising or prior to a game/meet/race - at least 30 minutes before your scheduled appointment time.
- Please make sure you are well-hydrated prior to exercising.
- Wear comfortable clothes for exercise – layers are recommended. No dresses, please. Wear tennis (running) type shoes. Avoid wearing sandals, slippers or high heels.
How is a Continuous Laryngoscopy during Exercise test carried out?
- Before the testing begins, a technician will use a local anesthetic gel to numb one of your nostrils.
- ECG electrodes will be placed on your chest to monitor your heart.
- Your blood pressure will be taken before (and after) you exercise.
- You will be asked to blow into a tube before (and after) you exercise to check how well your lungs are working.
- A pulse oximeter will be placed on your fingertip to monitor your oxygen.
- You will wear a harness for safety on the treadmill.
- A provider (doctor or advanced practice provider) will pass a laryngoscope through the nasal passage to the back of the throat to visualize the larynx from above. You will wear a mask and some light headgear to hold the scope in place as you exercise.
- You will then be asked to run, or walk up an incline, on the treadmill.
- You will be monitored before, during and after you exercise.
- Once your testing is complete, you will review the preliminary results of the test with the provider present. The provider will then recommend treatment options.
How long will this test take?
A Continuous Laryngoscopy during Exercise test often takes 1.5 hours. Actual exercise does not take the full time. Some of the time period is to prepare you for the test and observe you after the test.
Where will this test take place?
A Continuous Laryngoscopy during Exercise test will always take place within the Exercise and Performance Breathing Center, located on the 5th floor of the Center for Outpatient Health.
If you have questions, please call Pulmonary Physiology Services at 303-398-1530.
©National Jewish Health, 10/2025
