The interactive effects of physical activity and sedentary behaviors during childhood on adiposity in early adulthood

项目摘要 2018年身体活动指南科学报告总结了最新的证据， 表明，对于年轻人来说，身体活动对预防肥胖的影响的证据是强有力的，但 久坐行为的影响的证据仍然有限。报告指出， 知识差距，其中之一是关于身体活动的独立和互动影响， 久坐行为对健康的影响在整个身体活动指南的突然差异， 从青年到成年的过渡阶段（例如，青年人每天一小时，成年人每周2.5小时）， 被认为有问题。为了解决这些差距，我们建议进行汇总分析，以量化 成年早期体力活动和久坐行为对肥胖的独立和交互作用。 主要的假设是：（1）在儿童和成年早期， 与成年早期较低的肥胖相关，独立于久坐行为，和（2）更健康 久坐不动的行为模式与成年早期较低的肥胖有关， 健康的身体活动模式。本研究的第一个目的是检查不同的轨迹模式， 中等强度和高强度的体力活动和久坐行为，从11岁到24岁，使用 基于群体的双轨迹分析方法。第二个目标是通过以下方式比较22-24岁的肥胖率： 中等强度和高强度的身体活动和久坐行为轨迹模式。两个次级目标 是：检查是否健康的身体活动和/或久坐不动的行为模式与一个人的健康有关。 在患有早期儿童肥胖症的儿童中，22-24岁的肥胖症风险较低;并检查剂量- 中等强度和高强度体力活动和久坐行为与脂肪的反应关系 青年向成年过渡期（从15-17岁到22-24岁）的大规模变化。为了实现这些目标， 我们将使用来自三个出生队列研究的汇总数据：雅芳家长和孩子纵向研究， 巴西1993年骨盆研究和美国爱荷华州骨发育研究。汇集的数据将使我们能够有一个 样本多样性和足够的功效进行亚组分析。这个低成本的独立R 03项目是 预计将产生新的知识，通过解决这些知识更新身体活动指南 差距。

Project Summary The 2018 Physical Activity Guidelines Scientific Report, which summarized the most up-to-date evidence, suggested that, for youth the evidence for the effects of physical activity on obesity prevention is strong but the evidence for the effects of sedentary behavior remains limited. The report recognizes several important knowledge gaps, one of which is regarding the independent and interactive effects of physical activity and sedentary behavior on health outcomes. The abrupt difference in the physical activity guidelines across the transitional stage from youth to adulthood (e.g., daily one hour for youth vs. weekly 2.5 hours for adults) is also recognized as problematic. To address these gaps, we propose to conduct a pooled analysis to quantify the independent and interactive effects of physical activity and sedentary behavior on adiposity in early adulthood. The main hypotheses are (1) a healthier physical activity pattern during childhood and early adulthood is associated with lower adiposity in early adulthood, independent of sedentary behavior, and (2) a healthier sedentary behavior pattern is associated with lower adiposity in early adulthood only among those with a less healthy physical activity pattern. The first aim of this study is to examine the diverse trajectory patterns of moderate- and vigorous-intensity physical activity and sedentary behavior from age 11 to 24 years, using a group-based dual trajectory analysis approach. The second aim is to compare adiposity at age 22-24 years by moderate- and vigorous-intensity physical activity and sedentary behavior trajectory patterns. Two sub-aims are: to examine whether healthier physical activity and/or sedentary behavior patterns are associated with a lower risk of obesity at age 22-24 years among children with early childhood obesity; and to examine a dose- response relationship of moderate- and vigorous-intensity physical activity and sedentary behavior with fat mass change in the youth to adult transition period (from age 15-17 to 22-24 years). To achieve these aims, we will use pooled data from three birth cohort studies: U.K. Avon Longitudinal Study of Parents and Children, Brazil 1993 Pelotas Study, and U.S. Iowa Bone Development Study. The pooled data will enable us to have a diverse sample and sufficient power for the subgroup analysis. This low-cost self-contained R03 project is expected to produce new knowledge to update the Physical Activity Guidelines by addressing these knowledge gaps.