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

Approximately 92 million U.S. adults (\~38% of population) have prediabetes (PreD). Because people with PreD are at high risk CMD, they are a target population for diabetes prevention programs. The focus is people with PreD because of their high risk for developing CMD and large numbers, providing an opportunity to investigate behavioral and environmental approaches as preventive measures in a well-defined population. Urbanization affords challenges and opportunities to public health that include exposure to obesogenic environments, air pollution, and psychosocial stressors. In healthy adults suggest exposure to nature has health benefits relative to exposure to built environments. Hypothesized mechanisms for health benefits of Greenspace exposure include increased physical activity (PA), attention restoration, stress reduction, and reduced exposure to pollution. Many of the health benefits are associated with reduced psychological and physiological stress leading to better autonomic functioning as assessed by heart rate variability (HRV) and other biomarkers. Multiple studies suggest that PA and exposure to natural environments may act together to improve health. Yet, aside from our preliminary studies, we are not aware of any studies that examined how physical activity may interact with exposure to urban Greenspace (\'Green\') compared with built urban environments (\'Gray\'), to reduce stress and improve health. The purpose of this proposed study is to conduct a randomized crossover trial comparing differences in the psychosocial and physiological effects of walking in urban Green and Gray spaces in adults with PreD.