Towards Accurate Reference Values for Heart Rate and Speed Zones by Aerobic Fitness and Sex in Long-Distance Runners

This study aimed to provide reference values for estimating training intensities in long-distance runners based on progressive incremental tests, considering differences related to sex and performance level.

A total of 1411 endurance-trained runners (819 men and 592 women) completed a standardized treadmill protocol with gas exchange analysis to determine ventilatory thresholds and peak oxygen consumption (VO_2peak). Heart rate (HR) and running speed at each threshold were expressed relative to their peak values.

HR at second ventilatory threshold (VT2) occurred at 93.5 ± 2.5% of HR peak, and HR at first ventilatory threshold at 85.1 ± 4.6%. The relative running speeds at VT2 and VT1 corresponded to 87.6 ± 3.9% and 73.9 ± 5.5% of the speed at VO_2peak, respectively. In men, beginners exhibited higher relative HR and VO₂ values at the ventilatory thresholds than elite runners. In contrast, women displayed higher and more stable relative values across performance levels.

These findings establish precise, evidence-based reference ranges derived from a large cohort of runners and highlight the need to consider sex and performance level when estimating exercise intensities. Individualized physiological assessment remains essential for accurate training prescription and performance optimization.