Determination of heart rate threshold from heart rate kinetics during maximal graded exercise in soccer players

Abstract

The main of the present study was to identify the heart rate threshold based on heart rate kinetics during graded maximal exercise in football players. Twenty-six male football players performed a maximal exercise test (Bruce protocol) on a motor-driven treadmill. Oxygen uptake (VO2) and heart rate (HR) were monitored, recorded and resampled at 3.5Hz. The ventilatory threshold (VT), and respiratory compensation (RC), heart rate deflection points (HRDP1 and HRDP2) and heart rate kinetics threshold (HRT) were determined by computerized methods. The heart rate variability (HRV) was assessed in the frequency domain. The HRT averaged 89.9 ± 1.2 % of the VO2 peak. The HRT showed poor correlations and significant differences compared with HRDP1 (r = 0.46) and VT (r = 0.51), but was not different from, and highly correlated with, HRDP2 (0.98) and RC (0.90). Bland Altman plots showed all athletes into 95% of limits of agreement, and intraclass correlation coefficient showed good agreements between points obtained from HRT compared with HRDP2 (0.96) and RC (0.98). The HRT was highly correlated with HRDP2 and RC, suggesting it could be a marker for cardiorespiratory fatigue.

Effect of individual characteristics and aerobic training on the %HRR‐%V̇O2R relationship

“…Notwithstanding, when step‐incremental protocols are employed, studies descriptively show that, compared to ramp protocols, after an initial increase, HR (e.g. see (Marques Neto et al, 2019; Moser et al, 2018) and V̇ O 2 (e.g. see (Keir et al, 2016; Mauger & Sculthorpe, 2012; Zhang et al, 1991) trends tend to level‐off to match the metabolic demands of that stage, and the leveling‐off seems more pronounced and visible when the stages have lower intensities or longer durations.…”