Jaklik, D., Cholewa, D., Guzik, N., Starzyk, R., Śmiałek, S., Florek, J., … Miczek, M. (2026). Heart Rate Variability (HRV) as a Marker for Overtraining Syndrome Prevention in Endurance Athletes: A Systematic Review. Quality in Sport, 52, 69422. https://doi.org/10.12775/QS.2026.52.69422