Author(s): YANG, Y., WU, Y., WANG, J., FENG, Q., Institution: CHINA INSTITUTE OF SPORTS SCIENCE, GENERAL ADMINISTRATION OF SPORT OF CHINA, Country: CHINA, Abstract-ID: 1233

INTRODUCTION:
The residential exercise environment represents a critical external determinant of physical activity(PA) and health outcomes. However, in China, national-level evidence remains limited, particularly among older adults who experience declining mobility and increased dependence on their residential environment. Based on a national sample of older adults in China, this study examines the relationship between the number of exercise facilities near residential areas and physical fitness, tests the mediating role of PA, and conducts subgroup analyses across key population subgroups.
METHODS:
This study utilized data from the Sixth National Physical Fitness Surveillance of China, employing multistage stratified sampling to include 48,610 older adults aged 60-79 years from 31 provinces nationwide. Physical fitness was measured using the Physical Fitness Index (PFI), constructed by standardizing Z-scores from five indicators: 2-minute stepping test, grip strength, sit-and-reach , single-leg stance with eyes closed, and reaction time. PA was assessed using the Global Physical Activity Questionnaire (GPAQ) to calculate weekly moderate-to-vigorous PA(MVPA; minutes/week). Exercise environment data were obtained from Amap point-of-interest (POI) data, and the number of exercise facilities within a 2-km residential buffer was calculated. Multivariable linear regression was used to analyze associations between the number of exercise facilities and PFI, with subgroup analyses conducted by sex, urban-rural status, and economic development region (eastern, central, and western). Structural equation modeling (SEM) examined the mediating role of PA in this relationship, with separate mediation analyses performed for each stratified subgroup. Sensitivity analyses using a 1 km buffer zone verified the robustness of findings.
RESULTS:
After adjustment for age, sex, urban-rural status, and regional factors, multivariable regression analysis showed that the number of exercise facilities was positively associated with PFI (β = 0.037, P < 0.001). This positive association remained consistent across all subgroup analyses. Mediation analysis revealed that MVPA partially mediated this relationship in the overall sample (P < 0.001). In stratified analyses, the mediation remained statistically significant only among males, urban residents, and populations in eastern regions (all P < 0.001). Sensitivity analysis using a 1 km buffer zone produced results consistent with the primary analysis.
CONCLUSION:
This study found a consistent positive association between the number of exercise facilities and physical fitness among older Chinese adults. PA serves as a partial mediator in this relationship, with the magnitude of mediation varying systematically across sex, urban–rural residence, and regional economic development status.