Physical Activity, Sedentary Behavior and Weight Status in Early Childhood

在过去的三十年里，美国儿童肥胖症的患病率急剧上升， 这一趋势甚至在最年幼的儿童中也很明显。大约8%的婴儿和幼儿 身高比体重偏高，这会增加儿童时期患肥胖症和其他健康问题的风险， 超越。因此，主要的健康组织已经确定预防幼儿肥胖是一个关键的 公共卫生挑战。低水平的体力活动和高水平的久坐行为可能有助于 幼儿过度肥胖的发展，但这些关系尚未得到充分探讨。 在3岁及以上的儿童中，加速度计已被广泛用于测量身体活动和久坐不动的情况。 行为然而，它很少被用来测量婴儿和幼儿的身体活动水平， 仅在横断面研究中。以前的研究没有使用加速度计作为客观测量物理 幼儿从婴儿期到学龄前的发展过程中的活动。因此，人们对它知之甚少。 与幼儿身体活动行为发展相关的因素，目前知之甚少 关于身体活动和久坐行为的影响，客观地衡量，对发展的影响， 从婴儿期到3岁过渡期间的体重状况。本研究的第一个目的是描述物理 从婴儿期到学龄前儿童的活动和久坐行为。第二 目的是描述体重状况与体力活动和久坐行为的纵向联系 随着幼儿从婴儿期到学龄前的发展，拟议的调查将采用 纵向观察性研究设计。参加者将是160名儿童和他们的亲生母亲生活在 哥伦比亚，南卡罗来纳州。参与者将通过儿童保育中心，儿科实践， 教堂和社区组织。对于每个参与的儿童，测量将是 在6、12、18、24、30和36个月大时进行。在每个时间点，每个孩子的身体活动，久坐 行为，体重状况和运动发育状况将被客观地测量，每个孩子的母亲 将完成一项调查，以评估人口统计学、社会和物理环境因素; 里程碑;与身体活动和久坐行为有关的育儿实践;以及饮食习惯。 儿童保育中心主任将每年完成一次调查，以评估中心的特点， 环境和政策评估和观察（EPAO）将在孩子的教室里进行 每年。这项拟议中的研究将是重要的，因为它将显着扩大我们对 在前三个阶段，体力活动、久坐行为和肥胖症发展之间的关系 多年的生活。拟议的调查将是创新的，因为它将是第一个使用客观的 测量身体活动和纵向研究设计，检查身体活动模式， 它们与6至36个月儿童体重状况发展的关系。

The prevalence of childhood obesity in the U.S. has increased dramatically over the past three decades, and the trend has become evident even in the youngest children. Approximately 8% of infants and toddlers have high weight-for-length, which increases risk for developing obesity and other health problems in childhood and beyond. Thus, leading health organizations have identified prevention of obesity in young children as a critical public health challenge. Low levels of physical activity and high levels of sedentary behavior may contribute to the development of excessive fatness in young children, but these relationships have not been fully explored. In children ages 3 and above, accelerometry has been used widely to measure physical activity and sedentary behavior. However, it rarely has been used to measure physical activity levels in infants and toddlers, and then only in cross-sectional studies. No previous study has used accelerometry as an objective measure of physical activity in young children as they develop from infancy to preschool age. Accordingly, little is known about the factors associated with the development of physical activity behavior in very young children, and little is known about the influence of physical activity and sedentary behavior, measured objectively, on development of weight status during the transition from infancy to age 3. The first aim of this study is to describe physical activity and sedentary behavior in young children as they develop from infancy to preschool age. The second aim is to describe the longitudinal associations of weight status with physical activity and sedentary behavior as young children develop from infancy to preschool age. The proposed investigation will employ a longitudinal, observational study design. Participants will be 160 children and their biological mothers living in Columbia, South Carolina. Participants will be recruited through childcare centers, pediatrics practices, churches, and community organizations in Richland County. For each participating child, measurements will be taken at 6, 12, 18, 24, 30, and 36 months of age. At each time point, each child’s physical activity, sedentary behavior, weight status and motor developmental status will be measured objectively, and each child’s mother will complete a survey to assess demographic, social and physical environmental factors; gross motor milestones; parenting practices related to physical activity and sedentary behavior; and dietary practices. Childcare center directors will complete a survey annually to assess center characteristics, and the Environment and Policy Assessment and Observation (EPAO) will be administered in the child’s classroom annually. The proposed research will be significant because it will markedly expand our knowledge of the relationships among physical activity, sedentary behavior and development of adiposity during the first three years of life. The proposed investigation will be innovative because it will be the first to use objective measurement of physical activity and a longitudinal study design in examining physical activity patterns and their associations with development of weight status in children between the ages of 6 and 36 months.