Abstract -- The ability to accurately and reliably monitor physical activity and energy expenditure has emerged as a critical component to weight management and the prevention of lifestyle related health

The ability to accurately and reliably monitor physical activity and energy expenditure has emerged as a critical component to weight management and the prevention of lifestyle related health problems. Current methods and tools used by researchers, clinical practitioners, and individuals to assess physical activity and energy expenditure were reviewed and found to have practicality and accuracy limitations. Similarly, a competitive analysis of activity and energy expenditure detection devices found that accuracy varied considerably when used in the free-living environment because of their inability to detect energy expenditure during certain non-ambulatory activities. It was found that BodyMedia’s SenseWear Armband, which employs an array of physiologic sensors, overcame these limitations. In a structured energy expenditure study, the SenseWear Armband was found to be significantly more accurate and more reliable than the BioTrainer Pro and Sport-Tech Pedometer in determining Resting Energy Expenditure, Active Energy Expenditure and Total Energy Expenditure. Index of Terms -Accuracy, Active Energy Expenditure, Ambulatory, Caloric Tracking, Competitive Analysis, Context Detection, , FreeLiving Environment, Physiologic Data Sensors, Multiple Sensor Array, Ambulatory, Non-ambulatory, Resting Energy Expenditure, Total Energy Expenditure