Monitoring and Evaluation Branch, Swiss Federal Institute of Sport Magglingen, Magglingen, Switzerland.
J Phys Act Health. 2013 Sep;10(7):1057-67. doi: 10.1123/jpah.10.7.1057. Epub 2012 Nov 5.
Accelerometry has been established as an objective method that can be used to assess physical activity behavior in large groups. The purpose of the current study was to provide a validated equation to translate accelerometer counts of the triaxial GT3X into energy expenditure in young children.
Thirty-two children aged 5-9 years performed locomotor and play activities that are typical for their age group. Children wore a GT3X accelerometer and their energy expenditure was measured with indirect calorimetry. Twenty-one children were randomly selected to serve as development group. A cubic 2-regression model involving separate equations for locomotor and play activities was developed on the basis of model fit. It was then validated using data of the remaining children and compared with a linear 2-regression model and a linear 1-regression model.
All 3 regression models produced strong correlations between predicted and measured MET values. Agreement was acceptable for the cubic model and good for both linear regression approaches.
The current linear 1-regression model provides valid estimates of energy expenditure for ActiGraph GT3X data for 5- to 9-year-old children and shows equal or better predictive validity than a cubic or a linear 2-regression model.
加速度计已被确立为一种可以用于评估大群体身体活动行为的客观方法。本研究的目的是提供一个经过验证的公式，将三轴 GT3X 的加速度计计数转换为幼儿的能量消耗。
32 名 5-9 岁的儿童进行了适合其年龄组的运动和游戏活动。儿童佩戴 GT3X 加速度计，并通过间接热量法测量其能量消耗。21 名儿童被随机选择作为发展组。基于模型拟合，为运动和游戏活动分别制定了一个三次 2 回归模型。然后，使用其余儿童的数据对其进行验证，并与线性 2 回归模型和线性 1 回归模型进行比较。
所有 3 个回归模型都在预测的和测量的代谢当量值之间产生了很强的相关性。三次模型的一致性可接受，两种线性回归方法的一致性都很好。
目前的线性 1 回归模型为 5 至 9 岁儿童的 ActiGraph GT3X 数据提供了有效的能量消耗估计值，并且其预测有效性与三次或线性 2 回归模型相等或更好。
