Chen K Y, Sun M
Department of Biomedical Engineering and Medicine, Vanderbilt University, Nashville, Tennessee 37232-2279, USA.
J Appl Physiol (1985). 1997 Dec;83(6):2112-22. doi: 10.1152/jappl.1997.83.6.2112.
In our study of 125 subjects (53 men and 72 women) for two 24-h periods, we validated energy expenditure (EE), estimated by a triaxial accelerometer (Tritrac-R3D), by using a whole-room indirect calorimeter under close-to-normal living conditions. The estimated EE was correlated with the measured total EE for the 2 days (r = 0. 925 and r = 0.855; P < 0.001) and in minute-by-minute EE (P < 0.01). Resting EE formulated by the Tritrac was found to be similar to the measured values [standard errors of estimation (SEE) = 0.112 W/kg; P = 0.822]. The Tritrac significantly underestimated total EE, EE for physical activities, EE of sedentary and light-intensity activities, and EE for exercise such as stepping (all P < 0.001). We developed a linear and a nonlinear model to predict EE by using the acceleration components from the Tritrac. Predicted EE was significantly improved with both models in estimating total EE, total EE for physical activities, EE in low-intensity activities, minute-by-minute averaged relative difference, and minute-by-minute SEE (all P < 0. 05). Furthermore, with our generalized models and by using subjects' physical characteristics and body acceleration, EE can be estimated with higher accuracy (averaged SEE = 0.418 W/kg) than with the Tritrac model.
在我们对125名受试者（53名男性和72名女性）进行的为期两个24小时时段的研究中，我们在接近正常生活条件下，使用全室间接热量计对通过三轴加速度计（Tritrac - R3D）估算的能量消耗（EE）进行了验证。估算的EE与两天内测量的总EE相关（r = 0.925和r = 0.855；P < 0.001），并且与逐分钟的EE相关（P < 0.01）。发现由Tritrac得出的静息EE与测量值相似[估计标准误差（SEE）= 0.112 W/kg；P = 0.822]。Tritrac显著低估了总EE、体力活动的EE、久坐和轻度活动的EE以及诸如踏步等运动的EE（所有P < 0.001）。我们开发了一个线性模型和一个非线性模型，通过使用来自Tritrac的加速度分量来预测EE。在估算总EE、体力活动的总EE、低强度活动的EE、逐分钟平均相对差异和逐分钟SEE方面，两个模型预测的EE均有显著改善（所有P < 0.05）。此外，使用我们的广义模型并通过利用受试者的身体特征和身体加速度，可以比使用Tritrac模型更准确地估算EE（平均SEE = 0.418 W/kg）。
