The gold standard for measuring resting metabolic rate (RMR) is metabolic carts that measure oxygen consumption (VO2) and carbon dioxide production (VCO2). The energy equivalent of VO2 ranges from \~4.7-5.0 kcals/L, depending on the ratio of carbohydrate, fat, and protein oxidized. However, RMR can be measured based solely on VO2, because VCO2 has a relatively small effect on energy expenditure estimation. A device that measures RMR based on VO2 and eliminates the need for measuring VCO2 could provide a simple and less expensive alternative to metabolic carts and may have important clinical applications. The overarching goal of this proposal is to validate such a metabolic system by comparing its ability to accurately measure RMR against a metabolic cart.
