For the theme and purpose of this special issue, the STAPS journal has gone back to the original point of introduction of “Savoir s’entraîner” (“Knowing How to Train”) into French Physical Education (PE) school curricula. We gave a list of questions to Gilles Klein, president of the Physical Education Working Group from 1999 to 2002, to gain understanding of the gradual development of PE curricula and the slow, but sometimes stormy, emergence of “Savoir s’entraîner,” whether linked to specific physical activities or not.The initial set of questions reframes the historical context before 1999, and the challenges existing when school curricula were created. The second part focuses on the complex emergence of “Savoir s’entraîner,” the diversity of points of views on the subject, the links to health issues current at the time of drawing up the curricula, and the introduction of a new cultural field : physical activities for personal development and taking care of oneself.