Accuracy of energy expenditure estimates from the Lifecorder physical activity monitor

Abstract

The Lifecorder EX and Lifecorder Plus are accelerometers that can be used to evaluate exercise intensity and provide estimates of energy expenditure (EE). However, the accuracy of these devices for determining EE during activities of daily living has not been well studied. PURPOSE: The purpose of this study was to examine the accuracy of EE estimates from the Lifecorder EX during occupational, household, and recreational activities. METHODS: Thirteen subjects (3 men and 10 women; mean ± SD age: 22.4 ± 1.4; body mass: 71.5 ± 13.6 kg) volunteered for the study. Each subject performed a standardized set of activities that included 2 office work routines (O1 & O2), 3 housework routines (H1, H2, & H3), sweeping (S), vacuuming (V), lawn mowing (M), golf (G), and two basketball practices (BB1 & BB2). Each subject wore a Lifecorder EX on their waistband at the midline of the thigh while net EE was measured during each activity with a COSMED K4b2 indirect calorimetry system. Statistical analyses were performed using SPSS 11.0 with a significance level set at p<0.05. RESULTS: The 10 minute EE (net kcals) for the activities were:Table: Caption not availableThe Lifecorder measured activity intensity level ranged from 0.5 - 6 for both occupational and household activities and 2 - 8 for recreational activities. CONCLUSION: The results of this study suggest that the Lifecorder accelerometer does not provide accurate estimates of EE for most occupational, household, and recreational activities. An accepted limitation of these types of physical activity monitors is their inability to account for work performed with the arms. The inaccuracy was most evident for activities that require more upper body involvement such as sweeping and vacuuming.