Exercise-induced oxidative and hematological responses in adolescent female swimmers during the luteal phase

Introduction: Physiological response to exercise in young female athletes is understudied, especially regarding how the luteal phase of the menstrual cycle influences performance in demanding sports such as swimming. Therefore, this study aimed to evaluate the post-exercise cortisol response, oxidative stress markers, and hematological parameters following a moderate-intensity exercise test in trained adolescent female swimmers. Materials and methods: Eighteen swimmers (aged 12-16 years) performed a swimming test (800m + 200m + 50m) during their rigorously verified luteal phase. Blood samples were collected before exercise, immediately after exercise, and after 3 hours of recovery. It was registered retrospectively on clinicaltrials.gov under NCT06903195 (March 17, 2025). Results: Moderate-intensity exercise significantly increased 8-isoprostane levels (100.70 (40.50-131.00) vs 145.10 (99.16-190.40), p