Evaluating the Impact of Improvements in Urban Green Space on Older Adults' Physical Activity and Wellbeing: a Natural Experimental Study

Background: Creating or improving urban green space has the potential to be an effective and sustainable way to increase physical activity and improve other aspects of wellbeing in older adults. However, the size and quality of the existing evidence base is weak. There is particularly a lack of studies on older adults and in the United Kingdom. This study aims to evaluate the effect of four small local street greening intervention projects on older adults' physical activity and wellbeing over a one-year period. The street greening includes tree and flower planting, and artificial tree decorations. These projects are based in a deprived urban neighbourhood in Greater Manchester, United Kingdom.

Methods: Eight unimproved comparison sites were selected to compare with the intervention sites. The researchers will measure physical activity and two other behavioural indicators of wellbeing (Connect: connecting with other people; and Take Notice: taking notice of the environment) using a newly developed observation tool. It is thought that the largest effect of the interventions will be on Take Notice behaviour due to improvements in the aesthetic quality of green space at the intervention sites. Baseline data collection occurred in September 2017 before the interventions were installed in November 2017. Follow-up data collection will be repeated in February/ March 2018 (6 months) and September 2018 (12 months).

Discussion: The present study offers a rare opportunity to evaluate the before-and-after effects of small-scale changes in urban green space, in an understudied population (older adults) and setting (United Kingdom). Although the interventions are expected to have small effects on peoples' behaviour, this study will address key weaknesses in previous studies.