Purpose: Inducing a negative stereotype toward women usually leads to a decrease in women performance and an increase in men performance. These effects were observed during technical tasks. The purpose of the present study was to investigate the effect of this sex stereotype during a non-technical muscular endurance task. The perception of effort, closely related to endurance performance, was also recorded. Based on the type of task and the mere effort account, we predicted that both men and women in the negative stereotype toward women condition would perform better than participants in the two other groups. Method: Seventy-seven participants (38 women and 39 men) were randomly assigned to a negative stereotype toward women, a nullified-stereotype, or a control condition. Then, they performed a submaximal handgrip task until exhaustion at 50% of their maximal strength. Results: This study showed that performance at T2 was reduced for men and women in the nullified-stereotype and control conditions, but not in the negative stereotype toward women condition, revealing that participants in the negative stereotype toward women condition performed better than participants in the other conditions. No significant difference was observed concerning the perception of effort according to the conditions. Conclusion: As compared to technical tasks, inducing a negative stereotype toward women increased women's performance. The perception of effort could be responsible for this performance improvement. However, more research is needed to investigate the mechanisms involved. Concerning men, in line with the stereotype lift phenomenon, a performance increase was observed in this same condition.