1. Enhanced cardiac vagal efferent activity does not explain training-induced bradycardia
- Author
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Pascale Calabrese, Hélène Perrault, Veronika Lesiuk, Tuan Pham Dinh, Adrienne S. Scott, Gila Benchetrit, Dror Ofir, André Eberhard, Montreal Chest Institute, McGill University Health Center [Montreal] (MUHC), Laboratoire de Modélisation et Calcul (LMC - IMAG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications, Grenoble - UMR 5525 (TIMC-IMAG), VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Physiologie cardio-Respiratoire Expérimentale Théorique et Appliquée (TIMC-IMAG-PRETA), and VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)
- Subjects
Male ,Blood Pressure ,030204 cardiovascular system & hematology ,0302 clinical medicine ,Heart Rate ,MESH: Vagus Nerve ,Heart rate variability ,Medicine ,MESH: Heart Rate ,Vagal tone ,MESH: Teaching ,Tidal volume ,Fourier Analysis ,Respiration ,Vagus Nerve ,MESH: Blood Pressure ,MESH: Case-Control Studies ,Anesthesia ,Breathing ,Female ,medicine.symptom ,MESH: Efferent Pathways ,MESH: Physical Endurance ,Sports ,Adult ,Bradycardia ,Adolescent ,Respiratory rate ,MESH: Arrhythmia, Sinus ,Efferent Pathways ,MESH: Bradycardia ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Endurance training ,MESH: Analysis of Variance ,Heart rate ,[SDV.MHEP.PHY]Life Sciences [q-bio]/Human health and pathology/Tissues and Organs [q-bio.TO] ,Humans ,Arrhythmia, Sinus ,MESH: Adolescent ,MESH: Respiration ,Analysis of Variance ,MESH: Humans ,Endocrine and Autonomic Systems ,business.industry ,Teaching ,MESH: Adult ,MESH: Male ,Case-Control Studies ,Physical Endurance ,Neurology (clinical) ,MESH: Sports ,business ,MESH: Female ,MESH: Fourier Analysis ,030217 neurology & neurosurgery - Abstract
International audience; Studies of heart rate variability (HRV) have so far produced contradictory evidence to support the common belief that endurance training enhances cardiac parasympathetic tone. This may be related to the fact that most studies failed to specifically isolate the vagally mediated influence of respiration. This study used a cross-sectional comparison of endurance athletes (n=20; ATHL) exhibiting resting bradycardia and age-matched nonathletes (n=12; CRTL) to indirectly assess training effects on amplitude and timing characteristics of respiratory sinus arrhythmia (RSA). Continuous electrocardiogram (ECG) and ventilatory flows were recorded during spontaneous breathing (SP), as well as during breathing at four cycles less than (M4) or more (P4) than SP, to also examine potential repercussions of training on the sensitivity of the cardiac vagal responses to breathing. A fast Fourier transform procedure was used to quantify the standard spectral high-frequency (HF) and low-frequency (LF) components and a respiratory-centered frequency (RCF) component of HRV. RSA was assessed using a breath-by-breath quantification of the amplitude and timing of the maximum change in instantaneous heart rate. Under baseline SP conditions, heart rate was lower in ATHL (62.6+/-6.5 vs. 75.2+/-9 beats/min; p
- Published
- 2004