Effects of Walking in Greenspace and the Built Environment in Adults with Prediabetes: A Randomized Crossover Trial

项目摘要：鉴于糖尿病对健康和经济的严重不良影响， 预防糖尿病前期（美国成人患病率为38%）进展为2型糖尿病（T2 D）是一个主要的 公共卫生目标。环境在确定T2 D风险方面起着关键作用。城镇化 与心理社会压力增加和不良健康结果有关。压力反应会导致荷尔蒙 导致胰岛素抵抗、高血糖、炎症、氧化应激和肥胖的变化。增加 暴露于空气污染与糖尿病和心血管疾病的风险增加有关。 “绿色空间”被定义为具有主要自然主义元素的公共区域（例如，树木，草地， 水等）。先前对成年人的研究支持这样的假设，即暴露于绿色空间（“绿色”） 相对于城市建筑（“灰色”）环境，可能具有若干健康益处。这些好处可能包括更好的 通过心率变异性（HRV）改善、焦虑/压力减少和 加强心理恢复，绿地也有助于缓冲空气污染。走路是最 一种常见的中等强度体力活动，对血糖控制有有益的影响。 初步研究表明，散步和暴露在绿色空间可能共同作用，以改善健康 结果。然而，除了我们的初步研究外，还没有进行严格的实验研究， 研究与城市灰色空间相比，定期步行与城市绿地的相互作用， to improve改善health健康.需要进行这些研究来调查新颖且高度概括的“绿色”策略 运动”，能够在人群层面实施，以减轻疾病负担。所以我们 将进行一项机械随机交叉试验，以比较生理，心理，空气 在城市绿色和灰色中完成的步行干预之间的污染和心脏代谢风险措施 糖尿病前期的成年人。这项多地点试验将包括大都市地区的180名个人 of Minneapolis/圣保罗，MN和芝加哥，IL.步行干预将在城市绿色和城市 灰色环境，参与者在每个环境中每周步行150分钟，持续6周， 间隔5周的洗脱期。具体目标：目标1：测量和比较 绿色和灰色走。目的2：测量和比较绿色和 灰色行走。目标3：使用个人空气测量个人对环境颗粒物的实时暴露 当在绿色和灰色环境中行走时，使用GPS跟踪的污染监测器。目标4：衡量个人 心脏代谢疾病风险评分（血糖、胰岛素、血脂、收缩压和腰围指数） 和炎症因子之前和之后6周的绿色和灰色步行。目标5（探索性）：检查 是否生理，心理和空气污染措施调解不同的影响，绿色与 使用基于回归的中介模型对心脏代谢风险和炎症进行灰色步行。

PROJECT SUMMARY: Given the substantial adverse health and economic consequences of diabetes, preventing progression of prediabetes (prevalence of 38% in U.S. adults) to type 2 diabetes (T2D) is a major public health goal. The environment plays a critical role in determining risk for T2D. Urbanization has been associated with increased psychosocial stress and adverse health outcomes. Stress responses cause hormonal changes that lead to insulin resistance, hyperglycemia, inflammation, oxidative stress, and obesity. Increased exposure to air pollution has been associated with higher risk of diabetes and cardiovascular disease. ‘Greenspace’ is defined as publicly accessible areas with predominant naturalistic elements (e.g., trees, grass, water features, etc.). Previous studies in adults support the hypothesis that exposure to Greenspace (‘Green’) may have several health benefits relative to urban built (‘Gray’) environments. These benefits may include better autonomic functioning as assessed by improved heart rate variability (HRV), reductions in anxiety/stress, and enhanced psychological restoration, with Greenspace also serving to buffer air pollution. Walking is the most common form of moderate-intensity physical activity and has a beneficial influence on blood glucose control. Preliminary studies have suggested walking and exposure to Greenspace may act together to improve health outcomes. Yet, aside from our preliminary studies, rigorous experimental studies have not been conducted to examine how regular walking may interact with exposure to urban Greenspace, compared to urban Grayspace, to improve health. These studies are needed to investigate novel and highly generalizable strategies for “Green exercise”, capable of being implemented at the population-level to reduce the burden of disease. Therefore, we will conduct a mechanistic randomized crossover trial to compare differences in physiological, psychological, air pollution, and cardiometabolic risk measures between walking interventions completed in urban Green and Gray environments in adults with prediabetes. This multisite trial will include 180 individuals within metropolitan areas of Minneapolis/St. Paul, MN and Chicago, IL. Walking interventions will be completed in urban Green and urban Gray environments, with participants engaging in 150 minutes/week of walking for 6 weeks in each environment, separated by a 5-week washout. Specific Aims: Aim 1: Measure and compare psychosocial stress between Green and Gray walking. Aim 2: Measure and compare physiological stress over six weeks between Green and Gray walking. Aim 3: Measure real-time individual exposure to ambient particulate matter using personal air pollution monitors with GPS tracking while walking in Green and Gray environments. Aim 4: Measure individual cardiometabolic disease risk scores (index of blood glucose, insulin, lipids, systolic blood pressure, and waist) and inflammatory factors before and after 6 weeks of Green and Gray walking. Aim 5 (exploratory): Examine whether physiological, psychological, and air pollution measures mediate the differential impact of Green vs. Gray walking on cardiometabolic risk and inflammation using regression-based mediation models.