Physical activity during the transition from elementary school to middle school

描述(由申请人提供)：从儿童到青春期，体力活动随着年龄的增长而下降，在美国，很大比例的青少年不符合当前的体力活动指南。从小学到中学的过渡是年轻人生活中的一个关键发展阶段，也是许多儿童体力活动水平急剧下降的时期。以前的许多研究都考察了儿童和青少年体育活动行为的相关性。然而，之前没有研究前瞻性地、全面地研究年轻人随着时间的推移而改变身体活动行为的机制。同样，没有人使用客观的体力活动衡量标准和多层次分析方法。因此，本研究的目的是考察个人、家庭/家庭、邻里、学校和社区因素对非裔美国人和白人男孩和女孩从小学过渡到中学期间身体活动变化的直接和间接影响。还将研究性别、种族、社会经济地位和邻里环境对影响体力活动变化的因素的潜在调节作用。这项研究将涉及750名5年级学生和他们的家长，他们将参加5年级、6年级和7年级的测量方案。测量将包括通过加速计和自我报告测量的体力活动，以及在三个水平上测量的广泛的自变量--儿童/家庭/家庭/街道、小学/社区和中学/社区。儿童和父母将在每年家访期间提供数据，在此期间将填写问卷并进行人体测量。学校数据将通过与学校工作人员的面谈获得，有关物理环境因素的信息将通过对街道路段的挡风玻璃调查、应用详细的地理信息系统数据库、对体育活动场所的审计和自我报告的环境感知来衡量。将使用多层次结构方程建模程序来确定与三个年级的体力活动变化直接或间接相关的因素。这项研究将通过显著扩展我们对影响青少年体育活动行为发展的因素的认识，来应对一个关键的公共卫生挑战。这些知识是未来旨在增加儿童和青少年体力活动和预防肥胖的公共卫生干预措施所必需的。与公共健康相关：美国年轻人的肥胖率飙升，体力活动减少可能是这一令人担忧的趋势的原因之一。在从小学到中学的过渡过程中，许多儿童的体力活动水平急剧下降，而这种变化背后的因素还没有得到很好的理解。这项研究将应用复杂的数据收集和数据分析技术来确定导致儿童进入青春期时体力活动水平下降的关键因素。

DESCRIPTION (provided by applicant): Physical activity declines with increasing age through childhood and adolescence, and a large percentage of adolescents in the U.S. do not meet current physical activity guidelines. The transition from elementary school to middle school is a critical developmental stage in the lives of young people, and it is a period during which physical activity levels decline dramatically in many children. Many previous studies have examined the correlates of physical activity behavior in children and adolescents. However, no previous studies have prospectively and comprehensively studied the mechanisms that underlie change in physical activity behavior over time in young people. Likewise, none have used an objective measure of physical activity and multi-level analytic methods. Therefore, the aims of the proposed study are to examine the direct and indirect influences of personal, home/family, neighborhood, school and community factors on changes in physical activity in African American and white boys and girls as they transition from elementary school to middle school. The potential moderating effects of gender, race, socioeconomic status, and neighborhood environment on factors influencing changes in physical activity also will be examined. The study will involve 750 5th grade students and their parents, who will participate in a measurement protocol at 5th, 6th and 7th grades. Measures will include physical activity measured by accelerometry and self-report and a wide range of independent variables measured at three levels -- child/family/home/street, elementary school/neighborhood, and middle school/community. Data will be provided by children and parents during annual home visits during which questionnaires will be completed and anthropometric measures will be administered. School data will be acquired through interviews with school personnel, and information on physical environmental factors will be measured by windshield surveys of street segments, application of a detailed Geographic Information Systems database, audits of physical activity places, and self-reported perceptions of the environment. Multi-level structural equation modeling procedures will be used to identify factors that are directly or indirectly associated with change in physical activity across the three grade levels. This study will address a critical public health challenge by markedly expanding our knowledge of the factors that influence development of physical activity behavior in youth. This knowledge is needed to inform future public health interventions aimed at increasing physical activity and preventing obesity in children and adolescents. PUBLIC HEALTH RELEVANCE: Obesity rates have skyrocketed in American youth, and declining physical activity is a likely cause of this alarming trend. Physical activity levels decrease dramatically in many children during the transition from elementary to middle school, and the factors that underlie that change are not well understood. This study will apply sophisticated data collection and data analysis techniques in identifying the key factors that cause physical activity levels to decrease as children transition into adolescence.