Individualized Physical Conditioning Based on Heart Rate Variability and Workload Monitoring in Table Tennis Players

This study compares two 12-week conditioning programs in 48 competitive table tennis players. Players were randomly assigned to an experimental group or a control group. The experimental group followed an individualized conditioning program in which training intensity, volume, and content were adjusted weekly according to each athlete's morning heart-rate variability (HRV, 5-minute supine rMSSD) and acute:chronic workload ratio (ACWR) computed from session-RPE training load. On days when HRV fell more than one standard deviation below the athlete's rolling 7-day average, high-intensity components were replaced with low-intensity work. The control group followed a standardized conditioning program matched for session frequency (three integrated sessions per week for 12 weeks, no individualized monitoring feedback). The program progressed through eight phases (foundation, accumulation, deload, intensification, transition, taper I-II, peak/post-test). Both groups were assessed before and after the intervention on 24 measures of neuromuscular performance (jump height, reactive strength index, rate of force development, force asymmetry, EMG onset latency and peak amplitude), sensorimotor performance (simple and saccadic reaction time, movement time, balance), cardiorespiratory fitness (VO2max, heart-rate recovery, blood lactate), and competitive match performance (win rate, stroke accuracy, placement accuracy, rally efficiency, ball speed, national ranking points). The primary outcome is simple reaction time. The study tests whether readiness-guided individualization improves performance more than standardized conditioning. The study protocol, dataset, and analysis code are openly available in the Zenodo repository (DOI: 10.5281/zenodo.21343993).