Energy Expenditure: Indirect Calorimetry
The 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.