The Institute for Sport, Physical Education and Health Sciences, The Moray House School of Education, The University of Edinburgh, St Leonard's Land, Holyrood Road, Edinburgh EH8 8AQ, Scotland.
Int J Behav Nutr Phys Act. 2014 Mar 30;11(1):45. doi: 10.1186/1479-5868-11-45.
Understanding how the determinants of behaviour vary by context may support the design of interventions aiming to increase physical activity. Such factors include independent mobility, time outdoors and the availability of other children. At present little is known about who children spend their time with after school, how this relates to time spent indoors or outdoors and activity in these locations. This study aimed to quantify who children spend their time with when indoors or outdoors and associations with moderate to vigorous physical activity (MVPA).
Participants were 427 children aged 10-11 from Bristol, UK. Physical activity was recorded using an accelerometer (Actigraph GT1M) and matched to Global Positioning System receiver (Garmin Foretrex 201) data to differentiate indoor and outdoor location. Children self-reported who they spent time with after school until bed-time using a diary. Each 10 second epoch was coded as indoors or outdoors and for 'who with' (alone, friend, brother/sister, mum/dad, other grown-up) creating 10 possible physical activity contexts. Time spent and MVPA were summarised for each context. Associations between time spent in the different contexts and MVPA were examined using multiple linear regression adjusting for daylight, age, deprivation and standardised body mass index.
During the after school period, children were most often with their mum/dad or alone, especially when indoors. When outdoors more time was spent with friends (girls: 32.1%; boys: 28.6%) than other people or alone. Regression analyses suggested hours outdoors with friends were positively associated with minutes of MVPA for girls (beta-coefficient [95% CI]: 17.4 [4.47, 30.24]) and boys (17.53 [2.76, 32.31]). Being outdoors with brother/sister was associated with MVPA for girls (21.2 [14.17, 28.25]) but not boys. Weaker associations were observed for time indoors with friends (girls: 4.61 [1.37, 7.85]; boys: (7.42 [2.99, 11.85]) and other adults (girls: 5.33 [2.95, 7.71]; boys: (4.44 [1.98, 6.90]). Time spent alone was not associated with MVPA regardless of gender or indoor/outdoor location.
Time spent outdoors with other children is an important source of MVPA after school. Interventions to increase physical activity may benefit from fostering friendship groups and limiting the time children spend alone.
了解行为决定因素在不同环境下的变化情况，可能有助于设计旨在增加身体活动的干预措施。这些因素包括独立出行能力、户外活动时间以及其他儿童的存在。目前，对于儿童放学后与谁在一起、这与室内或室外活动时间的关系以及在这些地点的活动情况知之甚少。本研究旨在量化儿童在室内或室外与谁在一起，以及与中等到剧烈身体活动（MVPA）的关联。
参与者为来自英国布里斯托尔的 427 名 10-11 岁儿童。使用加速度计（Actigraph GT1M）记录身体活动情况，并与全球定位系统接收器（Garmin Foretrex 201）数据相匹配，以区分室内和室外位置。儿童使用日记记录放学后直至睡觉时间与谁在一起。每 10 秒的时间片段被编码为室内或室外，并根据“与谁一起”（独自、朋友、兄弟姐妹、父母、其他成年人）进行编码，创造了 10 种可能的身体活动情境。总结每个情境下的活动时间和 MVPA。使用多元线性回归，根据日光、年龄、贫困程度和标准化体重指数对不同情境下的活动时间与 MVPA 之间的关联进行调整。
在放学后期间，儿童与父母或独自在一起的情况最为常见，尤其是在室内。当在户外时，与朋友在一起的时间（女孩：32.1%；男孩：28.6%）多于与其他人或独自在一起的时间。回归分析表明，女孩（β系数[95%CI]：17.4 [4.47，30.24]）和男孩（17.53 [2.76，32.31]）与朋友在户外的时间与 MVPA 呈正相关。与兄弟姐妹在户外时，女孩的 MVPA 也呈正相关（21.2 [14.17，28.25]），但男孩则不然。在室内与朋友（女孩：4.61 [1.37，7.85]；男孩：7.42 [2.99，11.85]）和其他成年人（女孩：5.33 [2.95，7.71]；男孩：4.44 [1.98，6.90]）在一起的时间与 MVPA 也呈弱相关。无论性别或室内/室外位置如何，独自活动的时间均与 MVPA 无关。
放学后与其他儿童在户外度过的时间是中等到剧烈身体活动的重要来源。为了增加身体活动，干预措施可能会受益于培养友谊群体和限制儿童独自活动的时间。
