title: Effect of a training week on heart rate variability in elite youth rugby league players.
abstract: The aim of this study was to examine the influence of weekly training including a competitive game on heart rate (HR) variability (HRV). Youth players (n=9, age 17-20 years) were monitored during daily supine rest (10 min) and standing (8 min), 5 times over 8 days. Heart rate recordings were analysed for time domain, frequency (e. g. low frequency [LF], high frequency [HF]) domain and non-linear measures of HRV and compared using ANOVA or Friedman's tests. Relationships between HRV and training workloads were examined via Spearman rank rho (ρ) correlation coefficients. Prior to a game, mean HR was significantly increased and remained elevated until 2 days post-game while parasympathetic modulations (HF) were significantly reduced (p<0.05). The supine to standing change in HRV was significantly reduced for up to 4 days post-game (LF/HF ratio, - 1.0±2.9 vs. - 3.0±1.9, p<0.05). These results confirm that prior to a game, players exhibited reduced parasympathetic and/or predominant sympathetic modulation with the game significantly reducing autonomic responses to standing for up to the following 4 days. Identification of day to day fluctuations in HRV may provide a helpful tool for monitoring player workload to maximise training and game performance.
authors.affiliation: Institute of Sport and Exercise Science, James Cook University, Townsville, Australia.
authors.forename: R C
authors.initials: RC
authors.lastname: Edmonds
authors.forename: W H
authors.initials: WH
authors.lastname: Sinclair
authors.forename: A S
authors.initials: AS
authors.lastname: Leicht
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D054874:Athletic Performance / Q000502:physiology*; D001341:Autonomic Nervous System / Q000502:physiology; D003163:Competitive Behavior / Q000502:physiology; D005538:Football / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D011187:Posture / Q000502:physiology; D012146:Rest / Q000502:physiology; D018709:Statistics, Nonparametric; D055815:Young Adult