Influence of activity monitor location and bout duration on free-living physical activity.

The purpose of this study was to evaluate the influence of the location (ankle, hip, wrist) where an activity monitor (AM) is worn and of the minimum bout duration (BD) on physical activity (PA) variables during free-living monitoring. Study 1 participants wore AMs at three locations for 1 day while wearing the Intelligent Device for Energy Expenditure and Activity (IDEEA) system. Study 2 participants wore AMs at the same locations for 3 days. Variables included time (T(MV), min/day) and AEE (AEE(MV) kcal/day) for each monitor location and BD above a moderate-vigorous (MV) intensity. T(MV) and AEE(MV) in Study 1 were similar across AMs to IDEEA values at BD = 10 min, as was T(MV) in Study 2. This suggests that ankle-, wrist- and hip-worn AMs can provide similar PA outcome values during free-living monitoring at 10-min BDs.