Validation of two novel monitoring devices to measure physical activity in healthy women.

Measurement of physical activity is increasingly important in health research. We sought to determine the accuracy and sensitivity to non-exercise activity of three activity monitors worn simultaneously by healthy adult women participating in a structured activity protocol. Ten normal-weight women wore the Intelligent Device for Energy Expenditure and Activity (IDEEA), the SmartShoe, and the SenseWear Armband, during activities that included standing, sitting still, sitting and fidgeting, lying down, and walking at varying speeds. Percentage of time postures correctly identified was determined for the IDEEA and the SmartShoe, and activity counts collected from all three devices were compared. Posture was detected with high accuracy by both the IDEEA and the SmartShoe (97.4% and 94.2% accuracy, respectively). The SmartShoe showed superior sensitivity to movement while seated ("fidgeting") compared with the IDEEA (p=0.004 and 0.049 difference between postures, respectively); all three devices distinguished between fast and slow walking. Data support the ability of the IDEEA and the SmartShoe to recognize basic postures in healthy normal-weight women, as well as to detect fidgeting within the seated position.