Episode 55 : The Female Athlete Code Mastering Your Cycle & Avoiding the RED-S Trap 🧬

Episode 55 : The Female Athlete Code Mastering Your Cycle & Avoiding the RED-S Trap 🧬💬 Got a question or feedback? Write us at: [email protected]☕ Buy a Gel Caf for Lactate to support the work: ko-fi.com/lactateSummary: For over a century, endurance sports operated on the flawed assumption that women were simply small men, leading to catastrophic misapplications of training loads and fueling strategies. The female bioenergetic environment is continuously modulated by 17β-estradiol and progesterone, where systemic estrogen enhances long-chain fatty acid uptake and suppresses hepatic gluconeogenesis during the late follicular and mid-luteal phases ; however, while these molecular shifts in substrate utilization are verified, network meta-analyses prove their translation to actual measurable physical performance across cycle phases is statistically trivial. Rather than paralyzing your programming with rigid cycle-syncing algorithms, which frequently mistime hormonal phases due to massive biological variance, you must track subjective wellness metrics like perceived exertion and prioritize real-time auto-regulation over shifting VO₂ workloads based on assumptions ; elite programming must avoid Low Carbohydrate Availability by matching intake directly to glycolytic session demands to prevent the neuroendocrine collapse of Relative Energy Deficiency in Sport (REDs). An energy deficit independently triggers a severe hypothalamic triage protocol, suppressing T3, halting luteinizing hormone pulsatility, and causing catastrophic skeletal demineralization, a state dangerously masked by the synthetic hormones of oral contraceptive pills. The visceral reality of this physiological starvation was exposed when distance running prodigy Mary Cain suffered three years of amenorrhea and five broken bones under a toxic, weight-obsessed coaching paradigm.Keywords: female athlete, menstrual cycle, relative energy deficiency in sport, low carbohydrate availability, bioenergetics, endocrinology, amenorrhea🎙️ Lactate, the podcast that deciphers science to improve your performance.Key references :Mountjoy, M., Ackerman, K. E., Bailey, D. M., et al. (2023). 2023 International Olympic Committee's (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine, 57(17), 1073-1097. 10.1136/bjsports-2023-106994McNulty, K. L., Elliott-Sale, K. J., Dolan, E., et al. (2020). The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis. Sports Medicine, 50(10), 1813-1827. 10.1007/s40279-020-01319-3Colenso-Semple, L. M., D'Souza, A. C., Elliott-Sale, K. J., & Phillips, S. M. (2023). Current evidence shows no influence of women's menstrual cycle phase on acute strength performance or adaptations to resistance exercise training. Frontiers in Sports and Active Living, 5. 10.3389/fspor.2023.1054542Elliott-Sale, K., et al. (2023). The effects of oral contraceptives on exercise performance, substrate oxidation, and hypertrophy. Journal of Applied Physiology, 135(4). 10.1152/japplphysiol.00346.2023Schlie, Krassowski, and Schmidt. (2025). Methodological standards in menstrual cycle research. Journal of Applied Physiology. 10.1152/japplphysiol.00223.2025Voices generated by artificial intelligence from the scientific report produced by the Lactate team.