The effect of light rail transit on physical activity: a natural experiment

项目摘要/摘要 轻轨交通对身体活动的影响：一项自然实验 大多数美国成年人无法获得足够的体力活动，尽管这对健康有很多好处 与更活跃相关的。越来越多的人对环境因素感兴趣，并有证据表明 影响体育活动，如社区设计和交通基础设施，一直受到 横断面设计限制了推断因果关系的能力。本研究利用了一种 交通环境即将发生显著变化，南方引入轻轨交通(LRT) 金县(西雅图地区)和附近可能发生的轻轨车站周围建成环境的变化，以 更好地了解建筑环境对交通相关步行和整体身体状况的因果影响 活动。采用病例对照纵向面板控制设计，1000名成年人居住在接近(1 1英里半径；情况)或远离(控制)轻轨车站，在人口统计和初始情况下相似 社区建筑环境，将在(基线)之前、之后不久(后1)和2以上进行评估 轻便铁路服务推出数年后(后2)。据推测，居住在轻轨附近的居民将 增加了与交通相关的步行(例如，从家到单位往返轻轨车站)和 无论是短期还是长期，相对于居住在更远的地方的居民的体力活动。短期内 增长可能仅限于轻轨用户，但假设交通运输的长期增长 步行和全部体力活动将由轻轨的使用和轻轨周围建筑环境的变化而产生 促进步行的车站。这些变化将包括增加居住密度、土地利用组合和 零售通道和步行基础设施。个人的交通步行将通过7天的旅行进行评估 通过加速度计评估日记和体力活动。邻里建筑环境及其变化 将通过地块级别的土地利用评估进行评估。此外，现有非轻轨交通的变化 基础设施(例如，公共汽车路线)和可用性也将得到考虑。对变化的前瞻性评估 在预期发生显著变化的一段时间内，相同个人的交通工具和体力活动 交通资源和建成的环境是罕见的，但有力地考验了环境可以产生的影响 健康行为。这样的评估是需要的，以推动主动生活研究等领域的发展 重要的是，更好地向政策制定者通报交通系统和 建筑环境。项目叙事 轻轨交通对身体活动的影响：一项自然实验 拟议的项目对公共卫生政策和研究具有重要意义，并对健康产生影响 美国日益增长的公共交通系统及其对建筑环境领域的更广泛影响 和体力活动。这种能力可以更好地从建筑环境对 与交通相关的全部体力活动对于告知建筑环境改造是否可以 唤起这种必要的健康行为变化，因此对公共卫生政策的制定至关重要。

Project Summary/Abstract The effect of light rail transit on physical activity: a natural experiment The majority of U.S. adults fail to obtain adequate physical activity, despite the numerous health benefits associated with being more active. Growing interest in and evidence regarding the environmental factors that affect physical activity, such as neighborhood design and transportation infrastructure, has been hampered by cross-sectional designs that limit the ability to draw causal inference. The present study takes advantage of an upcoming marked change in the transportation environment, the introduction of light rail transit (LRT) in south King County (Seattle area) and likely changes in the neighborhood built environment around LRT stations, to better understand the causal effects of built environment on transportation-related walking and overall physical activity. Using a case-control longitudinal panel controlled design, 1000 adults living either close to (within 1 mile radius; case) or far from (control) an LRT station who are similar demographically and in initial neighborhood built environment, will be assessed prior to (baseline), soon after (post 1), and more than 2 years after (post 2) the introduction of LRT service. It is hypothesized that residents living close to LRT will have an increase in transportation-related walking (e.g., to/from LRT stations from home, work) and total physical activity relative to residents living farther away in both the short- and long-term. The short-term increases will likely be confined to LRT users, but it is hypothesized that long-term increases in transport walking and total physical activity will result from LRT use and changes in the built environment around LRT stations that promote walking. Such changes would include increases in residential density, land use mix and retail access, and pedestrian infrastructure. Individuals' transport walking will be assessed via 7-day travel diaries and physical activity assessed via accelerometry. Neighborhood built environment and changes therein will be assessed via parcel-level land use evaluation. In addition, changes in existing non-LRT transportation infrastructure (e.g., bus routes) and availability will also be considered. The prospective evaluation of changes in the same individuals' transport modes and physical activity over a period of expected marked change in transportation resources and built environment is a rare, but potent test of the impact environment can have on health behaviors. Such evaluations are needed to move forward the field of active living research and more importantly to better inform policy makers regarding consequences of changes in transportation systems and the built environment. Project Narrative The effect of light rail transit on physical activity: a natural experiment The proposed project has significance for public health policy and research, with health impact implications for the growing public transportation system in the U.S. and broader implications for the field of built environment and physical activity. This ability to better draw causal inference from the impact of built environment on transportation-related and total physical activity is critical to informing whether built environment modification can evoke such needed health behavior changes and is therefore essential to informing public health policy.