Jones Melissa A, Diesel Sara J, Gibbs Bethany Barone, Whitaker Kara M
Department of Health and Human Physiology, University of Iowa, Iowa City, IA, USA.
Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, USA.
J Meas Phys Behav. 2022 Jun;5(2):69-75. doi: 10.1123/jmpb.2021-0050. Epub 2022 Apr 23.
Current best practice for objective measurement of sedentary behavior and moderate-to-vigorous intensity physical activity (MVPA) requires two separate devices. This study assessed concurrent agreement between the ActiGraph GT3X and the activPAL3 micro for measuring MVPA to determine if activPAL can accurately measure MVPA in addition to its known capacity to measure sedentary behavior.
Forty participants from two studies, including pregnant women ( = 20) and desk workers ( = 20), provided objective measurement of MVPA from waist-worn ActiGraph GT3X and thigh-worn activPAL micro3. MVPA from the GT3X was compared with MVPA from the activPAL using metabolic equivalents of task (MET)- and step-based data across three epochs. Intraclass correlation coefficient and Bland-Altman analyses, overall and by study sample, compared MVPA minutes per day across methods.
Mean estimates of activPAL MVPA ranged from 22.7 to 35.2 (MET based) and 19.7 to 25.8 (step based) minutes per day, compared with 31.4 min/day (GT3X). MET-based MVPA had high agreement with GT3X, intraclass correlation coefficient ranging from .831 to .875. Bland-Altman analyses revealed minimal bias between 15- and 30-s MET-based MVPA and GT3X MVPA (-3.77 to 8.63 min/day, > .10) but with wide limits of agreement (greater than ±27 min). Step-based MVPA had moderate to high agreement (intraclass correlation coefficient: .681-.810), but consistently underestimated GT3X MVPA (bias: 5.62-11.74 min/day, < .02). For all methods, activPAL appears to better estimate GT3X at lower quantities of MVPA. Results were similar when repeated separately by pregnant women and desk workers.
activPAL can measure MVPA in addition to sedentary behavior, providing an option for concurrent, single device monitoring. MET-based MVPA using 30-s activPAL epochs provided the best estimate of GT3X MVPA in pregnant women and desk workers.
目前用于客观测量久坐行为和中等到剧烈强度身体活动（MVPA）的最佳实践需要两种独立的设备。本研究评估了ActiGraph GT3X和activPAL3 micro在测量MVPA方面的一致性，以确定activPAL除了已知的测量久坐行为的能力外，是否还能准确测量MVPA。
来自两项研究的40名参与者，包括孕妇（n = 20）和办公室职员（n = 20），提供了佩戴在腰部的ActiGraph GT3X和佩戴在大腿的activPAL micro3对MVPA的客观测量数据。使用任务代谢当量（MET）和基于步数的数据，在三个时间段内将GT3X的MVPA与activPAL的MVPA进行比较。通过组内相关系数和Bland-Altman分析，按总体和研究样本比较了不同方法下每天的MVPA分钟数。
activPAL的MVPA平均估计值为每天22.7至35.2分钟（基于MET）和19.7至25.8分钟（基于步数），而GT3X为31.4分钟/天。基于MET的MVPA与GT3X具有高度一致性，组内相关系数范围为0.831至0.875。Bland-Altman分析显示，基于15秒和30秒MET的MVPA与GT3X的MVPA之间偏差最小（-3.77至8.63分钟/天，p > 0.10），但一致性界限较宽（大于±27分钟）。基于步数的MVPA具有中度到高度一致性（组内相关系数：0.681 - 0.810），但始终低估GT3X的MVPA（偏差：5.62 - 11.74分钟/天，p < 0.02）。对于所有方法，在较低的MVPA量时，activPAL似乎能更好地估计GT3X。孕妇和办公室职员分别重复测量时结果相似。
activPAL除了能测量久坐行为外，还能测量MVPA，为同时使用单一设备进行监测提供了一种选择。在孕妇和办公室职员中，使用30秒activPAL时间段基于MET的MVPA对GT3X的MVPA估计最佳。
