Indirect Calorimetry Make an Appointment Ask a Question Search Conditions An indirect calorimetry test requires two simple 10-minute breathing tests. It measures your daily resting energy expenditure (your calorie needs at rest). This translates into your actual metabolic rate. This translates into your actual metabolic rate. This test replaces predictive measures. The test results will provide you with an individualized calorie goal that can help you meet your weight management goals. Preparing for the Test Test preparation requires that you/your child have no food, calorie-containing drinks, or caffeine 4 hours before the test. Water and caffeine-free, calorie-free drinks are allowed. Avoid exercise for 4 hours prior to the test. During the test During this test, you breathe into a mouthpiece on a handheld device while sitting at rest. The device is portable so it will take place in the dietitian’s office. If you are an inpatient the test will take place in your room. Length of the Test The appointment will take about 30 minutes. On the day of your scheduled test, report to the adult clinic check-in. If you are an inpatient, the test will take place in your room. If you have questions please call 303.398.1889. This information has been approved by Michelle MacDonald, MS, RDN, CDE (August 2019).