A method and system for determining energy expenditure (EE) are disclosed. The method comprises determining a plurality of sensor streams using a plurality of detected physiological signals and processing the plurality of sensor streams to determine the EE. The system includes at least one sensor to detect a plurality of physiological signals, a processor coupled to the at least one sensor, and a memory device coupled to the processor, wherein the memory device includes an application that, when executed by the processor, causes the processor to determine a plurality of sensor streams using a plurality of detected physiological signals and to process the plurality of sensor streams to determine the EE.
