Research continues to shed light on multiple pathways through which access to nature has positive impacts on health. One such pathway is the influence of nature on mental health through stress relief. Some evidence suggests that physical health is positively impacted too. For example, urban greenness, including both parks and street greenery, can foster positive perceptions of neighborhood. These perceptions can, in turn, influence pro-health behaviors such as walking. Yet findings on this association in urban settings are mixed.
CUPC affiliate Amanda Carrico and colleagues disentangle some of the health-environment research in their recently-published paper “A Study of Perceived Nature, Shade and Trees and Self-Reported Physical Activity in Denver” in the International Journal of Environmental Research in Public Health. Carrico and colleagues contend that the exhibited association may vary as a result of the use of objective “greenness” measures and/or subjective perceptions of neighborhood environmental aesthetics.
The Neighborhood Environment and Health Survey provided the study’s data, covering 92 block groups in Denver, Colorado with a sample of 1,151 households. To explore the objective/subjective question, an objective measure of greenness was added – the Normalized Vegetation Index.
Results suggest a stronger association between perceived greenness and activity as compared to objective measures. In particular, respondents’ stronger perception of trees, shade, and the presence of nature was associated with higher levels of moderate physical activity such as jogging, cycling, and walking fast. On the other hand, the objective measure — NDVI — showed no such association.
The researchers argue that perceptions of greenneess capture a broader sense of neighborhood comfort (e.g. publicly-available shade), aesthetics, as well as safety. In contrast, objective measures capture aspects of nature that may be less associated with broader neighborhood perceptions including lawns and groundcover, including in backyards.
In all, the research suggests that neighborhood-based strategies geared toward enhancing environmental appeal hold potential to increase physical activity and, therefore, population health.
