Temporal Dynamics of Autonomic Nervous System Responses and Hormonal Balance after High-Load Effort in Weightlifters

Omar Khalid Yasser, Marwa Husein Ali and Haider Alaa Mohammed Ali

Abstract

This study analyzed the synchronized temporal dynamics of autonomic nervous system (ANS) responses and hormonal balance following high-load weightlifting in trained athletes. A repeated-measures design was employed with 16 weightlifters who completed a session at 85–90% of their one-repetition maximum (1RM), including the snatch and clean and jerk. Heart rate variability (HRV) indices (RMSSD and LF/HF), testosterone (T), cortisol (C), and the T/C ratio were measured at four intervals: pre-exercise, immediately post-exercise, 30 minutes post-exercise, and 24 hours post-exercise. Findings indicated a significant decrease in RMSSD and an increase in LF/HF immediately post-exercise, reflecting acute sympathetic dominance. These levels showed gradual recovery within 30 minutes and near-complete restoration by 24 hours. Cortisol increased significantly post-exercise and remained elevated at 30 minutes before returning to baseline at 24 hours; however, testosterone levels remained stable. This resulted in a transient reduction in the T/C ratio, indicating a short-term catabolic shift. Correlation analysis revealed an inverse relationship between RMSSD and cortisol, and a positive relationship between RMSSD and the T/C ratio, confirming functional integration between autonomic regulation and the HPA axis. High-load weightlifting produces an acute, adaptive neurohormonal response. Complete recovery within 24 hours suggests the training load was within an optimal physiological range. These findings underscore the value of integrating HRV and hormonal markers to monitor training loads and recovery in elite strength sports.