Social return on investment of physical activity and sport (PAS): The Japan findings.

This study investigates Japan's national Social Return on Investment (SROI) of physical activity and sport (PAS) by adapting the pioneering UK model to reflect Japan's sociocultural and policy context. As this study is the first national-level SROI model for PAS in Asia, it addresses a key research gap and responds to calls for geographical diversification. The conservative base-case model quantified the social value of PAS by monetizing outcomes with stronger consensus evidence, including health improvements and subjective well-being, while accounting for sport-related injuries to avoid overclaiming. Education-related outcomes, less-established health outcomes, volunteer labor as an organizational human resource benefit, and crime-related outcomes were examined only as supplementary or reference scenarios because of methodological uncertainty, limited causal evidence, or potential double-counting concerns. Data were drawn from national surveys and official statistics focusing on the year 2022. We identified a total input of approximately ¥4.07 trillion (USD 31.3 billion) and a conservative base-case outcome value of approximately ¥11.87 trillion (USD 91.3 billion), after applying a 20% deadweight adjustment to positive outcomes, which resulted in an SROI ratio of 2.92. Furthermore, the sensitivity analysis revealed that the SROI ratio ranged from 2.55 to 3.28 under alternative deadweight assumptions, and from 2.67 to 3.15 under alternative WVA assumptions. A reference scenario including all excluded or reference outcomes except crime produced an SROI ratio of 2.98. This implies that for every dollar invested in PAS, a return of approximately three dollars in social value can be expected in the base-case model, with the overall conclusion remaining robust across tested scenarios. These findings underscore the importance of individual sport participation as a key driver of social value in Japan, where demographic challenges, such as aging and rising healthcare costs, persist. In particular, the concentration of health-related value among older adults highlights the policy relevance of PAS for healthy aging and healthcare cost containment in Japan. This research offers critical insights for policymakers seeking evidence-based justification for investment in PAS and contributes to the development of a globally harmonized yet context-sensitive framework for SROI modeling in public health and sport policy.