Influence of 2nd Generation Oral Contraceptives on Muscle Recovery following Repeated Resistance Exercise in Trained Females

Abstract

ABSTRACT Purpose Oral contraceptives are commonly used by female athletes, but their effects on skeletal muscle are still poorly understood. We investigated if physically trained females using 2nd generation oral contraceptives (OCs) differed from non-users of OCs in the recovery of muscle function and muscle damage markers following repeated resistance exercise sessions. Methods We recruited 20 trained 2nd generation OC-users and 20 trained non-users to perform three strenuous resistance exercise sessions. Before, and 3, 24, and 48 hrs post-exercise, blood samples were collected, and participants were evaluated for muscle soreness, maximal isometric and isokinetic muscle strength, vertical jump height, Wingate power performance, leg press strength, and intermittent recovery capacity (Yo-Yo test). All participants were provided with an energy-macronutrient-balanced diet during the experimental period. Results Following resistance exercise, maximal isometric and isokinetic muscle strength, rate of force development (RFD), vertical jump height, and Wingate peak and average power were reduced, while markers of muscle damage were increased in both groups (p < 0.05). OC-users experienced a greater reduction in isokinetic strength 3, 24, and 48 hrs post-exercise compared to non-users of OCs (interaction: p < 0.05). No other interactions were observed. Conclusions We demonstrate that measures of muscle strength recovery following three strenuous resistance exercise sessions are comparable between trained females using 2nd generation OCs and non-users of OCs. However, group differences were observed for isolated dynamic (isokinetic) muscle strength, suggesting a marginal benefit of not using OCs when accelerated recovery is needed.