Calibration of an accelerometer during free-living activities in children
Calibration of an accelerometer during free-living activities in children
复制标题
DOI：
10.1080/17477160701408809
复制
发表时间：
2007-01-01
影响因子：
--
通讯作者：
Riddoch, Chris
中科院分区：
文献类型：
--
作者：
Mattocks, Calum;Leary, Sam;Riddoch, Chris
目的。本研究旨在建立一个预测能量消耗的方程，并从12岁儿童的Actigraph加速度计输出中得出中等强度和高强度身体活动强度的切点。方法。儿童在佩戴Actigraph和便携式代谢装置的同时进行一系列活动（躺着、坐着、慢走、快走、跳房子和慢跑）。样本被分为开发组和验证组。在开发组中使用随机截距模型建立预测方程。通过计算一致性界限（实际能量消耗减去预测能量消耗）在验证组中对该方程进行评估。以耗氧量（VO₂）作为结果重新拟合能量消耗模型得出中等强度和高强度活动的阈值。结果。开发组包括163名儿童，验证组包括83名儿童。该方程根据年龄和性别进行了调整，能够从加速度计计数充分预测能量消耗。身体活动强度切点是从静息耗氧量得出的。根据年龄和性别调整后的中等强度（4梅脱）下限阈值为每分钟3581计数。高强度活动（6梅脱）的下限阈值为每分钟6130计数。结论。预测方程和得出的切点将有助于更好地解释12岁儿童Actigraph的输出。从中等强度到高强度身体活动的切点高于先前报道的值。
Objective. The aims of this study were to develop an equation to predict energy expenditure and to derive cut-points for moderate and vigorous physical activity intensity from the Actigraph accelerometer output in children aged 12 years. Methods. The children performed a series of activities (lying, sitting, slow walking, fast walking, hopscotch and jogging) while wearing an Actigraph and a portable metabolic unit. The sample was divided into a developmental and a validation group. Random intercepts models were used to develop a prediction equation in the developmental group. The equation was assessed in the validation group by calculating limits of agreement (actual minus predicted energy expenditure). Thresholds for moderate and vigorous activity were derived by refitting the energy expenditure model with VO2 as the outcome. Results. The developmental group comprised 163 children, while the validation group comprised 83 children. The equation, adjusted for age and gender, adequately predicted energy expenditure from accelerometer counts. Physical activity intensity cut-points were derived from resting VO2. The lower threshold for moderate intensity (four METs), adjusted for age and gender, was 3581 counts per minute. The lower threshold for vigorous activity (six METs) was 6130 counts per minute. Conclusion. The prediction equation and the derived cut-points will help to better interpret the output of the Actigraph in children aged 12 years. The cut-point for moderate to vigorous physical activity is higher than that reported previously.