Globally, nation states have concerns about health, and this has led to a proliferation of initiatives and policies, which either have a direct or indirect influence on education in schools. This article focuses specifically on how China, with the largest public education system in the world, has sought to transform the health of the nation through national curriculum reform informed by policies from other nations, which has significant implications for physical education (PE). Guided by Charmaz's (2014) grounded theory, 22 PE teachers from 13 secondary schools in the north of mainland China were interviewed to provide a unique insight into how changes in curriculum were taken up and responded to. Analysis of data from this study indicated that the demands of implementing the new curriculum have their origins in complexities that go beyond individual teachers' perceptions of health and change. Teachers expressed concerns about the reforms and there were several further contextual factors limiting the realisation of curriculum reform guided by the maxim of 'Health First'. Teachers were uncertain of how to enact changes and reorientate their practices so that they were in line with the expectations of developing health through PE. The development of an examination in PE also strongly influenced the teachers' perceptions of what to prioritise.