title: Typology of "Fatigue" by Heart Rate Variability Analysis in Elite Nordic-skiers.
abstract: This study investigated changes in heart rate variability (HRV) in elite Nordic-skiers to characterize different types of "fatigue" in 27 men and 30 women surveyed from 2004 to 2008. R-R intervals were recorded at rest during 8 min supine (SU) followed by 7 min standing (ST). HRV parameters analysed were powers of low (LF), high (HF) frequencies, (LF+HF) (ms(2)) and heart rate (HR, bpm). In the 1 063 HRV tests performed, 172 corresponded to a "fatigue" state and the first were considered for analysis. 4 types of "fatigue" (F) were identified: 1. F(HF(-)LF(-))SU_ST for 42 tests: decrease in LFSU (- 46%), HFSU (- 70%), LFST (- 43%), HFST (- 53%) and increase in HRSU (+ 15%), HRST (+ 14%). 2. F(LF(+) SULF(-) ST) for 8 tests: increase in LFSU (+ 190%) decrease in LFST (- 84%) and increase in HRST (+ 21%). 3. F(HF(-) SUHF(+) ST) for 6 tests: decrease in HFSU (- 72%) and increase in HFST (+ 501%). 4. F(HF(+) SU) for only 1 test with an increase in HFSU (+ 2161%) and decrease in HRSU (- 15%). Supine and standing HRV patterns were independently modified by "fatigue". 4 "fatigue"-shifted HRV patterns were statistically sorted according to differently paired changes in the 2 postures. This characterization might be useful for further understanding autonomic rearrangements in different "fatigue" conditions.
authors.affiliation: National Centre of Nordic-Ski, Research and Performance, Premanon, France.
authors.forename: L
authors.initials: L
authors.lastname: Schmitt
authors.affiliation: Université de Franche-comte, Besancon, France.
authors.forename: J
authors.initials: J
authors.lastname: Regnard
authors.affiliation: Clinical Research Methods Center, University Hospital of Besançon, Besançon, France.
authors.forename: A L
authors.initials: AL
authors.lastname: Parmentier
authors.affiliation: University Hospital of Besançon, Research Unit UMR6249, Chrono-Environment, Besançon, France.
authors.forename: F
authors.initials: F
authors.lastname: Mauny
authors.affiliation: Culture Sport Health Society and Exercise Performance, Health, University of Franche-Comté,Innovation Platform, Besançon, France.
authors.forename: L
authors.initials: L
authors.lastname: Mourot
authors.affiliation: French Ski Federation, 50 rue des Marquisats, Annecy, France.
authors.forename: N
authors.initials: N
authors.lastname: Coulmy
authors.affiliation: Institute of Sport Sciences and Physical Education (ISSUL), University of Lausanne, Lausanne, Switzerland.
authors.forename: G P
authors.initials: GP
authors.lastname: Millet
mesh_terms: D001341:Autonomic Nervous System / Q000502:physiology*; D005221:Fatigue / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D011187:Posture / Q000502:physiology; D025341:Principal Component Analysis; D012865:Skiing / Q000502:physiology*