The Promethion Core is a metabolic and behavioral phenotyping system. One, high-resolution respirometry correlates accurate energy expenditure with changes in behavior. Two, water vapor compensation enables respirometry analysis >3 days and longitudinal studies. Three, integration of high-resolution sensors measure general activity; body mass and food/liquid consumed; voluntary exercise via a running wheel; and induced exercise via a metabolic treadmill. Four, the Promethion Live software monitors the system performance in real-time, evaluates experiment progress, and reports data.