BACKGROUND Physical activity (PA) tends to decline during late childhood and adolescence. In Australia, this decline has been shown to occur particularly in non-organized PA (e.g. active play and informal sport). Using a social marketing approach, segments of youth may be identified and targeted based on their profile of alternative activities that compete with non-organized PA during the transition to adolescence. The objectives of this study were to identify and describe segments of youth whose participation in non-organized PA declined between 11 and 13 years, based on changes in other potential competing activities during this period. METHODS Data were sourced from Waves 4 and 5 of the Longitudinal Study of Australian Children. Participation in non-organized PA and thirteen alternative activities (e.g. video games, homework, sleep) were measured using 24-h time-use diaries. Analyses were limited to participants whose non-organized PA had declined between 11 and 13 years (n = 1043). Two-stage cluster analysis was conducted and segments were described using chi-square and t-tests. RESULTS Among the analytic sample, average non-organized PA participation declined by 87 min/day between 11y and 13y (p < 0.001). Two segments were identified (κ = 0.66). The 'Social Screens' segment (n = 143) had large increases in texting, emailing and social media use (+ 56 min/day, p < 0.001) and other internet use (+ 32 min/day, p < 0.001). Conversely, 'the Mainstream' segment (n = 900) had smaller increases in a wider range of activities, including other PA (organized PA, active transport, active chores/work) (+ 16.0 min/day, p < 0.001), homework/study (+ 9.5 min/day, p < 0.001) and electronic gaming (+ 6.7 min/day, p < 0.05). 'Social Screens' were more likely to attend public school, live in urban areas and have more advanced pubertal development (girls only). 'The Mainstream' were more likely to participate in PA and out-of-school activities. CONCLUSIONS The 'Social Screens' segment had a much larger increase in texting, emailing, social media and other internet use, and lower participation in overall PA and out-of-school activities, compared with 'the Mainstream'. Future research may trial PA promotion strategies to replace benefits that this segment may seek in competing activities (e.g. social PA apps).

中文翻译：

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“社交屏幕”和“主流”：在从童年到青春期的过渡中，无组织体育活动的纵向竞争者。

背景技术体育活动（PA）在儿童晚期和青春期趋于下降。在澳大利亚，已证明这种下降特别是在非组织性PA中发生（例如，活跃的比赛和非正式运动）。使用社会营销方法，可以根据青年人的细分活动概况和目标群体，这些青年人在过渡到青春期期间与无组织的PA竞争的替代活动的概况。这项研究的目的是根据此期间其他潜在竞争活动的变化，确定并描述在11至13岁之间参与非组织PA的年轻人群体。方法数据来自澳大利亚儿童纵向研究的第4和第5波。参与非组织的PA和13种替代活动（例如，视频游戏，家庭作业，睡眠）是使用24小时使用时间日记来测量的。分析仅限于非组织性PA下降11至13岁（n = 1043）的参与者。进行了两阶段聚类分析，并使用卡方检验和t检验描述了片段。结果在分析样本中，平均无组织的PA参与在11y和13y之间下降了87分钟/天（p <0.001）。确定了两个部分（κ= 0.66）。“社交屏幕”部分（n = 143）在短信，电子邮件和社交媒体使用方面（+ 56分钟/天，p <0.001）和其他互联网使用方面（+ 32分钟/天，p <0.001）有了很大的增长。相反，“主流”部分（n = 900）在更广泛的活动中增长较小，包括其他PA（有组织的PA，主动运输，主动家务/工作）（+ 16.0分钟/天，p <0.001），家庭作业/研究（+ 9。5分钟/天，p <0.001）和电子游戏（+ 6.7分钟/天，p <0.05）。“社会筛查”更有可能上公立学校，生活在城市地区，青春期发育更高（仅限女孩）。“主流”更有可能参加PA和课外活动。结论与“主流”相比，“社交屏幕”部分在短信，电子邮件，社交媒体和其他互联网使用方面的增长更大，而对整体PA和课外活动的参与度更低。未来的研究可能会尝试使用PA促销策略来替代该细分市场在竞争活动中可能寻求的收益（例如，社交PA应用程序）。生活在城市地区，青春期发育更先进（仅女孩）。“主流”更有可能参加PA和课外活动。结论与“主流”相比，“社交屏幕”部分在短信，电子邮件，社交媒体和其他互联网使用方面的增长更大，而对整体PA和课外活动的参与度更低。未来的研究可能会尝试使用PA促销策略来替代该细分市场在竞争活动中可能寻求的收益（例如，社交PA应用程序）。生活在城市地区，青春期发育更先进（仅女孩）。“主流”更有可能参加PA和课外活动。结论与“主流”相比，“社交屏幕”部分在短信，电子邮件，社交媒体和其他互联网使用方面的增长更大，而对整体PA和课外活动的参与度更低。未来的研究可能会尝试使用PA促销策略来替代该细分市场在竞争活动中可能寻求的收益（例如，社交PA应用程序）。与“主流”相比，参与公共广播和校外活动的比例较低。未来的研究可能会尝试使用PA促销策略来替代该细分市场在竞争活动中可能寻求的收益（例如，社交PA应用程序）。与“主流”相比，参与公共广播和校外活动的比例较低。未来的研究可能会尝试使用PA促销策略来替代该细分市场在竞争活动中可能寻求的收益（例如，社交PA应用程序）。