The aging population in China is accelerating. In the face of a large population aging transformation, how to ensure the basic rights of elderly people to participate in society, reduce major disease risk factors, and improve their quality of life in their later years has become an important issue of concern for government management departments and academic circles. Physical activity has good health benefits. Elderly people actively participate in moderate physical activity, which can effectively maintain their physical health and self-care ability, improve their quality of life in later years, and promote the formation of a positive and healthy aging model. The community built environment is an important material foundation for the daily physical activity of the elderly. However, China is in the historical process of rapid urbanization development, and the long-term growth management led planning and regulation strategy has formed a spatial form dominated by motor vehicles and with clear functional zoning, which is not conducive to physical activity for the elderly. Faced with the dual challenges of aging population and rapid urbanization, it is necessary to explore a new approach to planning and regulation that focuses more on individual health and quality of life.The social cognitive theory believes that individuals, behaviors, and the environment are interdependent and interconnected entities, and the impact of the environment on individual behavior is usually mediated by cognitive mechanisms. This process focuses on the impact of individual psychological activities on behavioral decision-making, emphasizing the individual’s perception and symbolization of the environment as an agent. The key to achieving proactive intervention in public health issues in the built environment is the objective perception of the built environment and the accurate positioning of its perception function. Unfortunately, existing research has focused more on the identification of health supporting built environment elements and less on the positioning of their perceptual functions, making it difficult to provide decision-making references for optimizing existing built environments to effectively intervene in health aging in urban spaces. Therefore, based on social cognitive theory, this article constructs an impact relationship model that covers the willingness of elderly people to engage in physical activity, subjective perception, and core built environment elements in residential areas and surrounding areas. From the perspective of perception and mediation, key built environment elements that affect elderly people’s willingness to engage in physical activity are identified and individual perception functions are obtained.Results show Landscape comfort (β=0.332), traffic safety (β=0.157), travel patency (β=0.146) and traffic convenience (β=0.079) are the subjective sensitive factors for the formation of physical activity willingness of the elderly, and the role of public security safety is not significant. This is not to negate the promoting effect of public security safety on physical activity among the elderly. However, in the current context of long-term social stability in China, the formation of physical activity willingness among the elderly has not generated a sensitive demand for public security safety in residential areas and surrounding built environments. In terms of built environment, the community opening form (ɑ=0.117), road network density (ɑ=0.579), NDVI (ɑ=0.172), rest and shelter facilities (ɑ=0.128) have positive effects, and the plot area (ɑ=-0.168) and intersection density (ɑ=-0.572) have negative effects, while the relationship between the density of bus stops and the accessibility of bus stops is not obvious. The reason may be that as the mobility of elderly people decreases, and their daily physical activities are gradually reduced to residential areas and surrounding areas that can be reached by walking, the impact of transportation convenience mainly based on public transportation is relatively limited. Mediation effect indicates that the form of community opening is the key factor affecting the traffic safety of the elderly, while the NDVI will affect the subjective perception of landscape comfort and travel patency, and then affect the formation of the physical activity willingness of the elderly. Some influence paths that fail to pass the Sobel-test reflect that the built environment in Dalian is not old enough or the corresponding built environment elements fail to effectively trigger the subjective perception differences of the elderly.

The capacity of older adults to maintain good health is an important guarantee for the high quality of their life, which is closely related to the built environment of activity destinations in residential areas. The relationship between the built environment of residential areas or neighborhoods and the health of older adults is a topic of particular interest in planning studies. However, existing research has paid less attention to the impact of built environment factors of neighborhood destinations on the active health of older adults and related spatial heterogeneity. Based on the concept of “background network,” the paper divides residential areas into various spatial units and selects commercial, medical, and recreational and fitness facilities as neighborhood destinations for older adults. Then, employing the geographically weighted regression model, the paper investigates the heterogeneity in the impact of built environment factors of neighborhood destinations on older adults’ active health in different residential spatial units. Empirical evidence from Dalian indicates that the proportion of landscape elements around convenience stores has a positive impact on the physical efficacy of older adults, with the impact exhibiting a weakening trend from north to south in the city; the proportion of steps around pharmacies has a negative impact on the emotional state of older adults, with this impact being greater in the southern part of the city; the green view ratio around food markets has a negative impact on the social adaptation of older adults, with this impact decreasing from the city center to the periphery. Furthermore, a positive correlation is identified between the health impact change of neighborhood destinations and the internal environment factors of residential areas. Based on these findings, the paper proposes corresponding planning suggestions, including multi-level optimization of environmental factors and upgraded the matching degree of the destinations with the environment of residential areas.

According to the Theory of Justice, the characteristics of vulnerable groups should be considered in realizing the mental health benefits of blue-green spaces, so as to promote substantive equity and welfare in cities. The unclear relationship between the blue-green space indicator system and the mental health of older adults at both the quantitative and qualitative levels has hindered the development of spatial justice and health equity in cities. Based on the theories of stress reduction and attention restoration, this paper uses the Hierarchical Linear Model to systematically explore the relationship between the qualitative (environmental characteristics and landscape patterns of parks and water bodies) and quantitative (visibility and accessibility) characteristics of blue-green spaces and the mental health of older adults. The research finds that in the spatial dimension, there is a significant difference in the relationship between the qualitative and quantitative indicators of blue-green space and the mental health of older adults, and the relationship between the availability, visibility, and accessibility of blue-green space and the mental health of older adults is weakened in turn. In the social dimension, resilient ecological spaces can regulate and buffer the negative impacts on the mental health of older adults that are brought about by unfavorable socio-economic factors like having no homeownership. The research can provide guidance for environmental design and the selection of planning indicators to improve the mental health of older adults, and give empirical evidence for reaching a more “equitable” layout of urban blue-green spaces, so as to promote the development of age friendly cities and green and healthy cities.