Strugnell Claudia, Turner Kyle, Malakellis Mary, Hayward Josh, Foster Charlie, Millar Lynne, Allender Steve
World Health Organization's Collaborating Centre for Obesity Prevention, Deakin Population Health, Deakin University, Geelong, Victoria, Australia.
Nuffield Department of Population Health, British Heart Foundation Centre on Population Approaches for Non-Communicable Disease Prevention, University of Oxford, Oxford, Oxfordshire, UK.
BMJ Open. 2016 Sep 6;6(9):e011478. doi: 10.1136/bmjopen-2016-011478.
The after-school period has been described as the 'critical window' for physical activity (PA) participation. However, little is known about the importance of this window compared with the before and during-school period among socioeconomically disadvantaged children, and influence of gender and weight status.
39 out of 156 (RR=25%) invited primary schools across 26 local government areas in Victoria, Australia, consented to participate with 856 children (RR=36%) participating in the wider study. The analysis sample included 298 Grade 4 and Grade 6 children (mean age: 11.2±1.1; 44% male) whom met minimum accelerometry wear-time criteria and had complete height, weight and health-behaviours questionnaire data. Accelerometry measured duration in daily light-intensity PA (LPA), moderate-to-vigorous PA (MVPA) and sedentary time (ST) was calculated for before-school=8-8:59, during-school=9:00-15:29 and after-school=15:30-18:00. Bivariate and multivariable linear regression analyses were conducted.
During-school represented the greatest accumulation of LPA and MVPA compared with the before and after-school periods. Boys engaged in 102 min/day of LPA (95% CI 98.5 to 104.9) and 62 min/day of MVPA (95% CI 58.9 to 64.7) during-school; girls engaged in 103 min/day of LPA (95% CI 99.7 to 106.5) and 45 min/day of MVPA (95% CI 42.9 to 47.4). Linear regression models indicated that girls with overweight or obesity engaged in significantly less LPA, MVPA and more time in ST during-school.
This study highlights the importance of in-school PA compared with after-school PA among socioeconomically disadvantage children whom may have fewer resources to participate in after-school PA.
课余时间被描述为参与体育活动（PA）的“关键窗口”。然而，与社会经济条件不利儿童的上学前和上学期间相比，这个窗口的重要性以及性别和体重状况的影响鲜为人知。
在澳大利亚维多利亚州26个地方政府辖区的156所受邀小学中，有39所（回复率=25%）同意参与，856名儿童（回复率=36%）参与了更广泛的研究。分析样本包括298名四年级和六年级儿童（平均年龄：11.2±1.1岁；44%为男性），他们符合最低加速度计佩戴时间标准，并有完整的身高、体重和健康行为问卷数据。加速度计测量了上学前8:00 - 8:59、上学期间9:00 - 15:29和放学后15:30 - 18:00的每日轻度体育活动（LPA）、中度至剧烈体育活动（MVPA）持续时间和久坐时间（ST）。进行了双变量和多变量线性回归分析。
与上学前和放学后相比，上学期间LPA和MVPA的累积量最大。男孩在上学期间每天进行102分钟的LPA（95%置信区间98.5至104.9）和62分钟的MVPA（95%置信区间58.9至64.7）；女孩在上学期间每天进行103分钟的LPA（95%置信区间99.7至106.5）和45分钟的MVPA（95%置信区间42.9至47.4）。线性回归模型表明，超重或肥胖的女孩在上学期间进行的LPA和MVPA明显较少，久坐时间更多。
本研究强调了在社会经济条件不利的儿童中，与课余体育活动相比，校内体育活动的重要性，这些儿童可能参与课余体育活动的资源较少。
