Rethinking urban design for health: a review of built environment and physical activity correlates in high-density Asian cities

Physical inactivity is a pressing public health challenge, especially in high-density Asian cities where public space is limited. While the neighbourhood built environment (BE) is a known determinant of physical activity (PA), evidence from such dense urban contexts remains fragmented. This scoping review synthesises quantitative evidence from 34 studies conducted in high-density Asian cities. It employs the ‘5Ds’ framework (Density, Diversity, Design, Destination Accessibility, Distance to Transit) to map context-specific BE–PA relationships, evaluate the framework’s applicability, and identify research gaps. Results reveal that Design and Destination Accessibility are the most consistent and robust predictors of PA, particularly for leisure physical activities. In contrast, Density and Diversity show complex, often non-linear associations, indicating potential threshold effects. Distance to Transit demonstrates a weaker, more limited relationship, primarily with walking. This review critically evaluates the 5Ds framework’s applicability in high-density Asian contexts, highlighting context-specific association patterns and identifying critical gaps to guide future empirical research.