Sex differences in performance exist in the athletic domain. The goal of this thesis is to understand, in a social psychological perspective, the role of sex stereotypes in the athletic performance, by examining two ways of influence: the one exerted through PE teachers, and the one exerted through the internalisation of stereotypes in the self and through their activation in evaluative contexts. This thesis shows that although teacher expectations were biased in favour of boys, they did not lead to sex inequalities in performance through self-fulfilling prophecies or perceptual biases (e.g., Jussim, Eccles, & Madon, 1996). However, the stereotype relative to male superiority in sports may affect the performance of girls who endorse it, this relation being explained by a low perception of competence. Moreover, this stereotype may also affect girls' performance when it is activated during the realisation of a motor task (Steele, 1997). In addition, negative stereotypes may positively influence people who are not concerned by the stereotype, by enhancing their self-confidence and task engagement. To conclude, this doctoral work corroborates the idea that sex inequalities in performance are not only due to sex differences in natural ability, but may be explained by cultural beliefs relative to sex differences in sporting and physical activities.
