Sex Is Not an Independent Predictor of Exercise-Induced Pain After Adjustment for Performance and Pain Sensitivity

Exercise-induced pain (EIP) is a transient pain phenomenon that emerges during physical exertion and resolves soon after exercise cessation. Despite being recognized as a performance-limiting variable in endurance sports, the mechanisms driving its interindividual variability remain poorly defined. We aimed to determine whether sex remains a significant predictor of EIP intensity after adjustment for performance and pain sensitivity.

This cross-sectional study enrolled 122 recreational athletes (61 males and 61 females), including 48 trail runners and 74 hikers. Participants provided self-reported data on demographics and training habits. Performance was evaluated using both external and internal load metrics: external load was represented by activity duration and effort-adjusted speed, while internal load was assessed using the rating of perceived exertion (RPE). Maximum and average EIP was rated on a numeric rating scale and combined into a pain composite score (PCS). Pain threshold and tolerance were measured using the cold pressor test. Associations between variables and pain outcomes were analyzed using generalized linear models.

No significant differences were observed in maximum or average EIP intensity, pain threshold, or pain tolerance between male and female athletes. Sex was not a significant predictor of the PCS after adjusting for external and internal exercise load. Neither pain threshold nor tolerance significantly predicted PCS, and these associations did not vary by gender.

In recreational endurance athletes, sex had no significant impact on EIP intensity when accounting for performance and pain sensitivity. These findings challenged traditional assumptions about sex-related pain differences.