Abstract: Coordinating “investment in physical assets” and “investment in human capital” represents a key pathway for upholding a people-centered approach and advancing the modernization of a large population. This framework holds significant guiding value for establishing a higher-level public fitness service system in the new era. Using methods such as literature review and case analysis, this study clarifies the theoretical meaning and internal logic of coordinating these two forms of investment within the public fitness public service system. It further examines potential challenges and implementation pathways for developing an enhanced public fitness service system during the 15th Five-Year Plan period. The study argues that such coordination entails: using targeted allocation of physical resources to meet diverse public needs, leveraging human capabilities to maximize the utility of physical assets, and integrating both dimensions to translate investments into tangible improvements in public well-being. During the 15th Five-Year Plan period, building a higher-level public fitness service system will face challenges including economic growth-induced fiscal constraints, rising service demands due to demographic shifts, fragmented governance among stakeholders, equity concerns stemming from digital and intelligent technologies, and inadequacies in performance evaluation mechanisms. To address these challenges, the study proposes the following recommendations: improve top-level design to foster a supportive development environment; promote standards to optimize resource allocation; enhance collaboration for coordinated governance; refine evaluation mechanisms to ensure benefits for the people; and boost digital capabilities and enhance the technical content of public services.