Are Neighborhood Greenspaces Associated with Leisure-time Physical Activity? Results from ELSA-Brasil Eight-year Follow-up

We investigated whether neighborhood greenspaces were associated with physical activity in adulthood over 3 cohort visits after considering perceived safety and neighborhood contextual factors. We also evaluated whether the association with greenspace varied by neighborhood socioeconomic status. Participants (N = 4,800) from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) residing in two Brazilian state capitals were evaluated in Visits 1 (2008-2010), 2 (2012-2014) and 3 (2017-2019). Greenspaces were categorized by quintiles of positive Normalized Difference Vegetation Index (NDVI) scores. Physical activity frequency was given by the number of visits at which participants reported moderate/vigorous physical activity (none, 1 or 2, and 3 visits). We used multinomial logistic regression. After adjustment for age, sex, education, research center, residence in slums, individuals in the 4th and 5th NDVI quintiles showed 73% higher odds of physical activity over 3 visits than those in the 1st quintile (4th quintile: 95%CI = 1.24-2.43; 5th quintile: 95%CI = 1.24-2.41). The strength of the association was attenuated after adjustment for perceived safety. After adjustment for contextual factors quantity of sidewalks and streetlights, the OR for the 4th and 5th NDVI quintiles decreased to 1.66 (95%CI = 1.18-2.33) and 1.62 (95%CI = 1.16-2.28), respectively. Finally, after including average household income per capita, the OR for physical activity in 3 visits for the 4th and 5th NDVI quintiles decreased to 1.48 (95%CI = 1.04-2.12) and 1.43 (95%CI = 1.00-2.04; p = 0.053), respectively. Greater greenspace contributed to sustained physical activity during the eight years of follow-up, indicating the potential contribution of public greenspaces to reducing health-related inequalities.