Self-Determination for Increasing Physical Activity

描述（由申请人提供）：美国儿童和青少年肥胖症的患病率日益增加，是对我们社会的主要健康威胁，特别是在少数民族和社会经济地位低（SES）的人群中。在青春期，身体活动（PA）减少，可能是儿童肥胖率上升趋势的重要因素。很少有证据表明，校本课程干预导致整体PA的增加。因此，这项提案将评估一个创新的以学生为中心的课后计划的有效性，以促进服务不足的青少年中PA的增加（例如，少数民族，社会经济地位低）。以学生为中心的干预与自我决定（动机）理论和社会认知理论是一致的，它强调提高PA的内在动机和行为技能。以学生为中心的计划中的青少年在制定计划时拥有所有权，选择产生乐趣和兴趣的体育活动，并在录像过程中产生自己的应对策略，以有效地改变PA。从我们的小组的初步数据表明，以学生为中心的PA计划的可行性，增加中度到充满活力的PA在服务不足的青少年在南卡罗来纳州。拟议的项目将使用一个以学校为基础的嵌套队列设计，以评估一个为期6个月的以学生为中心的计划与典型的课后计划，增加PA在服务不足的青少年的有效性。位于南卡罗来纳州的24所中学（每所学校70名6年级学生; N=1,680）将被随机分配到两个课后项目中的一个。这项研究采用了嵌套队列设计，与学校，而不是个人分配到条件，并将使用重复测量分析的协方差技术，如默里概述。我们还将研究心理社会变量（PA自我效能，自我概念，动机，社会支持和享受）作为潜在的调解人的干预PA的变化，使用回归和结构方程建模技术所概述的男爵和肯尼。这项研究将解决一个重要的公共卫生问题，这将对减少服务不足的青少年肥胖产生影响。

DESCRIPTION (provided by applicant): The increasing prevalence of obesity in U.S. children and adolescents is a major health threat to our society, especially among minority and low social economic status (SES) populations. During adolescence physical activity (PA) decreases and is likely an important contributor to the increasing trend in childhood obesity rates. Little evidence suggests that school-based curriculum interventions lead to increases in overall PA. Thus, this proposal will evaluate the efficacy of an innovative student-centered after-school program for promoting increases PA among underserved adolescents (e.g., minorities, low SES). The student-centered intervention is consistent with Self-Determination (Motivation) Theory and Social Cognitive Theory in that it emphasizes increasing intrinsic motivation and behavioral skills for PA. Adolescents in the student-centered program take ownership in developing the program, select physical activities that generate fun and interest, and generate their own coping strategies for making effective PA changes during a videotaped session. Preliminary data from our group demonstrates the feasibility of the student-centered PA program for increasing moderate-to-vigorous PA in underserved adolescents in South Carolina. The proposed project will use a school-based nested cohort design to evaluate efficacy of a 6-month student-centered program versus typical after-school program on increasing PA in underserved adolescents. Twenty-four middle schools (70 6th graders per school; N=1,680), located in South Carolina will be randomly assigned to one of two after-school programs. The study employs a nested cohort design, with schools, rather than individuals assigned to condition and will be analyzed using repeated measures analysis of covariance techniques as outlined by Murray. We will also examine psychosocial variables (PA self-efficacy, self-concept, motivation, social support, and enjoyment) as potential mediators of the intervention on changes in PA using regression and structural equation modeling techniques as outlined by Baron and Kenny. This study will address an important public health problem that will have implications for decreasing obesity in underserved adolescents.