title: Longitudinal changes in cardiac autonomic function and aerobic fitness indices in endurance runners: a case study with a high-level team.
abstract: To determine the effects of preparatory phase training on aerobic parameters, resting heart rate variability (HRV) and 5-km performance of high-level endurance runners and the relationship between the percentage change (% change) of resting HRV with the % change of aerobic parameters and 5-km performance. Six runners were assessed before and after seven weeks of training. The aerobic parameters were determined in an incremental test. The HRV was assessed by a heart rate monitor. Athletes performed a 5-km running test in a track. The analysis revealed 'likely' and 'very likely' improvements for velocity associated with maximal oxygen uptake ([Formula: see text]O2max) (20.0±1.0 km·h(-1) to 21.2±0.6 km·h(-1)) and 5-km performance (18.0±0.4 km·h(-1) to 18.9±0.7 km·h(-1)), respectively, as well as 'likely' decrease in high frequency (41.4±18.5 nu to 30.4±14.3 nu), and increase in low frequency (58.5±18.5 nu to 69.6±14.3 nu) band densities. The variation in the velocity associated with [Formula: see text]O2max showed the highest correlation with 5-km performance (r=0.95). The % change in the square root of the mean sum of the squared differences between R-R intervals and standard deviation 1 were highly correlated with variation in 5-km performance (r=0.69 and 0.66). Changes in the velocity associated with [Formula: see text]O2max and vagally mediated HRV were highly associated with 5-km running performance within the investigated team. These results have important implications because these parameters can be assessed longitudinally to monitor adaptation to training.
authors.affiliation: a Department of Physical Education , State University of Maringá , Maringá , Brazil.
authors.forename: Danilo Fernandes
authors.initials: DF
authors.lastname: Da Silva
authors.forename: Samara Manzano
authors.initials: SM
authors.lastname: Verri
authors.forename: Fábio Yuzo
authors.initials: FY
authors.lastname: Nakamura
authors.forename: Fabiana Andrade
authors.initials: FA
authors.lastname: Machado
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D001341:Autonomic Nervous System; D005080:Exercise Test; D006321:Heart / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008991:Monitoring, Physiologic; D010101:Oxygen Consumption; D064797:Physical Conditioning, Human / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology*; D012420:Running / Q000502:physiology*; D055815:Young Adult
keywords: Parasympathetic activity; aerobic parameters; autonomic nervous system; endurance running