OHSU

Energy Expenditure: Indirect Calorimetry

Indirect CalorimetryThe indirect calorimetry equipment measures volume of oxygen consumption and volume of carbon dioxide output by placing a plexi-glass canopy over the head in a supine position.  Resting Energy Expenditure (REE) includes a 20 minute rest period followed by 30 minutes of data collection.  Energy expenditure (EE) and Respiratory Quotient (RQ), a measure of relative fat vs. carbohydrate oxidation, are determined.  Basal Metabolic Rate (BMR) can be determined with a protocol similar to the REE, involving an overnight stay the night before.  Thermic effect of food (TEF) can also be determined by feeding the participant a known quantity of food and monitoring EE and RQ for an additional 6 hours.  Length of measurements may vary per protocol guidelines.