In Japanese martial arts, the regulation of opposition does not lie on impersonal rules as in combat sports. Assuming that a control regulation from the teachers and an autonomous regulation from the learners jointly contribute to the solving of this concrete problem, this study tried (1) to identify and describe strategies used by the members (male and female) of a traditional private school to regulate the opposition on the tatami, and (2) to understand the rationality underlying these strategies. A qualitative analysis based on the use of several sources of data (interviews, observations, various documents) and of an original model revealed that what gender considered, the weakest practitioners were driven by a security stake. This common stake was coupled for men with a symbolic stake of preservation of their male sexual status, driving them to adopt tacit avoiding strategies. On the contrary, women negotiated openly with their rough partners, putting their feminine condition forward. The pedagogical intervention should take the existence of such a sexed autonomous regulation into account.