Performance and Physiological Effects of Race Pace-Based versus Heart Rate Variability-Guided Training Prescription in Runners.

Purpose: The aim of the present study was to compare performance and physiological effects, and inter-individual response variation in performance and its physiological determinants between heart rate-based (HR), race pace-based (RP) and heart rate variability-based (HRV) training prescription approaches in recreational distance runners.

Methods: Twenty-eight participants completed a 6-week endurance training intervention after being randomly assigned to three groups: HR (n = 9), RP (n = 9), and HRV (n = 10) training prescription approaches.

Results: No interaction effects between groups were observed. Main time effects were found for absolute and relative V̇O2max, running economy (RE), speeds associated to the first (sVT1) and second ventilatory thresholds (sVT2) and 7 km time trial performance (TT) (p < 0.001, 0.88 ≤ d ≤ 2.67). The RP group improved TT (p < 0.05, ES = 1.07), showing greater effectiveness in enhancing maximal aerobic speed and fat mass reduction, but did not consistently improve physiological parameters like sVT2 or RE. The HRV method increased sVT2 (p < 0.01, ES = 1.34) and was more successful in boosting sVT1 and V̇O2max, although it resulted in an increase in fat mass. Training load was similar between groups (p > 0.05), and a pyramidal training intensity distribution model was found in all groups. The lowest inter-individual response variation in TT was found in the RP group (coefficient of variation [CV] = 0.82), whereas the HRV group demonstrated a lower variation in relative V̇O2max (CV = 0.75) and sVT2 (CV = 0.79).

Conclusions: The RP approach is an effective and useful training prescription method for optimising performance in recreational runners, while the HRV method proves valuable for enhancing key physiological markers.