Reliability of resting and postexercise heart rate measures

• Published in: International journal of sports medicine Vol. 32; no. 8; p. 598
• Main Authors: Al Haddad, H, Laursen, P B, Chollet, D, Ahmaidi, S, Buchheit, M
• Format: Journal Article
• Language: English
• Published: Germany 01.08.2011
• Subjects: Exercise - physiology; Exercise Test; Heart Rate - physiology; Humans; Male; Reproducibility of Results; Vagus Nerve - physiology; Young Adult
• ISSN: 1439-3964
• DOI: 10.1055/s-0031-1275356

In this study, we compared the reliability of short-term resting heart rate (HR) variability (HRV) and postexercise parasympathetic reactivation (i.e., HR recovery (HRR) and HRV) indices following either submaximal or supramaximal exercise. On 4 different occasions, beat-to-beat HR was recorded in 15 healthy males (21.5 ± 1.4 yr) during 5 min of seated rest, followed by submaximal (Sub) and supramaximal (Supra) exercise bouts; both exercise bouts were followed by 5 min of seated recovery. Reliability of all HR-derived indices was assessed by the typical error of measurement expressed as a coefficient of variation (CV,%). CV for HRV indices ranged from 4 to 17%, 7 to 27% and 41 to 82% for time domain, spectral and ratio indices, respectively. The CV for HRR ranged from 15 to 32%. Spectral CVs for HRV were lower at rest compared with Supra (e.g., natural logarithm of the high frequency range (LnHF); 12.6 vs. 26.2%; P=0.02). HRR reliability was not different between Sub and Supra (25 vs. 14%; P=0.10). The present study found discrepancy in the CVs of vagal-related heart rate indices; a finding that should be appreciated when assessing changes in these variables. Further, Supra exercise was shown to worsen the reliability of HRV-spectral indices.