Validity of the Computer Science and Applications, Inc. (CCA) activity monitor

TLDR

The CSA accelerometer’s validity was assessed by comparing its activity counts to energy expenditure and to the Caltrac accelerometer during treadmill walking and running at three different grades. Both the CSA and Caltrac accelerometers were sensitive to treadmill speed changes, correlated strongly with energy expenditure, VO₂, and heart rate, and CSA‑derived models predicted energy expenditure with a mean error of 0.02 kcal/min, demonstrating comparable validity for estimating group energy expenditure.

Abstract

The validity of the Computer Science and Applications, Inc. (CSA) acclerometer in assessing physical activity was assessed during treadmill walking and runing at three differend grads. Energy expenditure (EE) served as the criterion measure. CSA data were compared to data collected with the Caltrac accelerometer. Both accelerometers were sensitive to changes in tradmill speed, but neither discriminated changes in teadmill grade. Caltrac and CSA data were compared to data collected with the Caltrac and CSA activity counts were significantly and similaryly correlatd with EE (r =0.66–0.82), relative V̇O2 (r =0.77–0.89), heart rate (r = 0.66–0.82), CSA data were used to develop models to predict EE (Kcal.min-1). Cross-validation resulted in a mean difference between actual and predictd E of 0.02Kcal.min-1 (SEE=0.85 Kcal.min-1). The range of individual diferences in the validation group was large for both the CSA model (-2.86 to +3.86 kcal.min −1) and Caltrac (-4.17 to +2.04 kcal.min-1). It is concluded that the CSA and Caltrac accelerometers have similar validity and that either instrument can be used to extimate EE of groups