You are here

Resize Text

Pulmonary Function & Exercise Testing

Pulmonary function tests (also called lung function tests) are used to measure how well your lungs work. They can also be used to diagnose conditions like asthma, chronic obstructive pulmonary disease (COPD), or pulmonary fibrosis, or to measure the damage done by conditions like pulmonary fibrosis or sarcoidosis.

To do this, pulmonary function tests measure:

  • How much air you can breathe in
  • How much air you can breathe out, and how fast you can breathe it out
  • How well your lungs are delivering oxygen to your blood
  • How strong your breathing muscles are

To measure these things, doctors use different breathing tests:

  • Spirometry: measures how much air you can breathe in and out and how and how fast you can breathe air out
  • Body plethysmography: measures how much air is in your lungs after you take a deep breath and how much is left in your lungs after you breathe out completely
  • Lung diffusion capacity: measures how well oxygen passes from your lungs to your blood

To measure the amount of oxygen in your blood, doctors use:

  • Pulse oximetry: uses a sensor attached to the finger that measures the amount of oxygen in the blood
  • Arterial blood gas test: determines how much oxygen is in the blood by examining a blood sample

Exercise testing is done to allow doctors to see how well your lungs perform during exercise. Exercise tests involve measuring your heart rate, carbon dioxide and oxygen levels in the blood, blood pressure, breathing patterns, and overall physical condition while you exercise. There are three main types of exercise tests:

  • Six-minute walk: involves walking on a treadmill at your own pace for six minutes
  • Rest and exercise test: involves mild exercise at different speeds to evaluate a patient’s oxygen requirements with everyday exertion
  • Incremental exercise test: involves exercise that is gradually increased in intensity to determine a patient’s maximum exercise capacity