Adolescent Physical Activity Decline In Girls

描述（由申请人提供）：在青春期，尤其是女孩，身体活动减少，这种减少在很大程度上导致了当前儿童/青少年肥胖的流行。在给定的时间点上，体力活动是一种高度复杂的行为，而体力活动减少的动态过程本身就更加复杂。更重要的是，由于青少年时期身体、社交和情感的快速成长，与体育活动减少相关的因素可能会从青少年早期到后期发生变化。包括人们生活环境（即政策、环境、社会、个人）在内的多层次生态模型现在被认为是描述包括身体活动在内的健康行为的最先进的方法。然而，这些多层次的生态框架尚未用于检查青春期女孩的身体活动，特别是影响青春期不同阶段体力活动减少的因素。我们的调查团队有独特的优势来研究女孩在青春期身体活动减少的复杂性。通过参与TAAG，我们获得了两大女孩群体在青春期早期的政策、环境、社会和个人层面的数据：1)参加TAAG的984名女孩（从6年级到8年级）的全国代表性队列，以及2)居住在马里兰州的700名不同种族/民族的8年级女孩。在这个应用程序中，我们建议对这些现在处于青春期中后期的女孩进行纵向随访（即11年级；“体育活动高中下降”[PAHSD]；新数据）。我们的目标是确定社会、环境和个人层面的因素，导致青少年早期和中后期身体活动减少。我们建议解决以下具体目标：(1)检查与青春期早期（6至8年级，TAAG）和青春期中后期（8至11年级，PAHSD）女孩体力活动减少相关的社区，学校，社会和个人层面的因素；(2)确定与青春期早期和青春期中后期体力活动减少相关的因素有何不同。鉴于全国对青少年肥胖日益普遍的关注，我们还将研究社区、学校、社会和个人层面的因素如何与青春期早期到中后期身体成分的变化相关联。公共卫生相关性：缺乏身体活动导致青少年健康状况不佳，并影响他们成年后的未来健康。为了制止青少年体力活动的减少，我们必须了解与这种减少有关的因素。本研究将探讨青春期女孩身体活动减少的多层次预测因素，这将为未来的干预设计提供信息，以阻止这种下降。

DESCRIPTION (provided by applicant): Physical activity declines during adolescence, particularly among girls, and this decline substantially contributes to the current child/adolescent obesity epidemic. Physical activity at a given point in time is a highly complex behavior, and the dynamic process of decline is inherently more complex. What's more, because of the rapid physical, social, and emotional growth that occurs during adolescence, factors associated with physical activity decline are likely to change from early to late adolescence. Multi-level ecologic models that include the context in which people live (i.e., policy, environment, social, individual) are now considered state-of-the-art for describing health behaviors, including physical activity. Yet these multi-level ecologic frameworks have not been used to examine physical activity in adolescent girls, particularly the factors influencing the decline at different phases of adolescence. Our investigative team is uniquely positioned to examine the complexity of physical activity decline in girls across adolescence. Through our participation in TAAG, we have policy, environmental, social, and individual-level data on two large cohorts of girls measured during early adolescence: 1) a nationally representative cohort of 984 girls who participated in TAAG (followed from 6th to 8th grade), and 2) 700 racial/ethnically diverse 8th grade girls residing in Maryland. In this application we propose to conduct a longitudinal follow-up of these girls who are now in mid-late adolescence (i.e., 11th grade; "Physical Activity High School Decline" [PAHSD]; new data). Our goal is to identify social, environmental, and individual-level factors that contribute to the decline in physical activity during early and mid-late adolescence. We propose to address the following specific aims: (1) To examine neighborhood, school, social, and individual-level factors associated with the decline in physical activity in girls in early adolescence (6th to 8th grade, TAAG) and mid-late adolescence (8th to 11th grade, PAHSD), and (2) To determine how factors associated with the decline in physical activity differ in early adolescence and mid-late adolescence. Given the national concern about the increasing prevalence of adolescent obesity, we will also examine how neighborhood, school, social, and individual-level factors are associated with change in body composition in early to mid-late adolescence. PUBLIC HEALTH RELEVANCE: Physical inactivity contributes to poor health among adolescents, and influences their future health as adults. To halt the physical activity decline in adolescents, we must understand factors associated with the decline. This proposed study will examine multi-level predictors of physical activity decline in adolescent girls, which will provide information for future intervention design to halt the decline.