title: Effects of interval and continuous exercise training on autonomic cardiac function in COPD patients.
abstract: OBJECTIVE
  Both interval (IT) and continuous (CT) exercise training results in an improvement of aerobic capacity in patients with chronic obstructive pulmonary disease (COPD); however, their effects on cardiac autonomic function remains unclear. The aim of our study was to evaluate the effect of a supervised CT vs IT on autonomic cardiac function in COPD patients.
  
  
  METHODS
  COPD patients were divided into two different groups according to training modality (IT or CT). Autonomic cardiac dysfunction (ACD) was defined as a heart rate recovery lower than 12 bpm heart rate after the first minute of maximal exercise (HRR1 ) and an abnormal chronotropic response (CR) to exercise (<80%).
  
  
  RESULTS
  A total of 29 patients {mean [standard deviation (SD)] age: 68 (8) years, %FEV1 : 42 (13) predicted} were trained (15 subjects in the CT group, 14 subjects in the IT group). After training, both groups increased peak oxygen consumption [mean difference ΔVO2 peak: 156 mL/min (P = 0.04) on IT; and 210 mL/min (P = 0.01) on CT], HRR1 [IT, from 10.4 (5) to 13.8 (5) bpm (P = 0.04); and CT, from 14.3 (5) to 17.7 (5) bpm (P = 0.04)] and CR [IT, from 57% (22) to 81% (9) (P = 0.001); and CT, from 48% (28) to 73% (17) (P = 0.001)]. Sixteen patients showed ACD. Among these patients, HRR1 (P = 0.01 for IT and P = 0.04 for CT) and CR (P = 0.001 for IT and P = 0.002 for CT) were enhanced after training.
  
  
  CONCLUSIONS
  Both IT and CT exercise training improve heart rate recovery and CR in COPD patients. These benefits could help to individualize exercise training.
authors.affiliation: Pulmonology Department, Hospital del Mar, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Pompeu Fabra (UPF), CIBERES, (ISCIII), Barcelona, Spain.|Pulmonology Department, Hospital Clínic i Provincial de Barcelona (ICT), CIBERES, IDIBAPS, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Diego A
authors.initials: DA
authors.lastname: Rodríguez
authors.affiliation: Pulmonology Department, Hospital Clínic i Provincial de Barcelona (ICT), CIBERES, IDIBAPS, Universitat de Barcelona, Barcelona, Spain.|Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.
authors.forename: Ane
authors.initials: A
authors.lastname: Arbillaga
authors.affiliation: Pulmonology Department, Hospital Clínic i Provincial de Barcelona (ICT), CIBERES, IDIBAPS, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Anael
authors.initials: A
authors.lastname: Barberan-Garcia
authors.affiliation: Pulmonology Department, Hospital del Mar, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Pompeu Fabra (UPF), CIBERES, (ISCIII), Barcelona, Spain.|Pulmonology Department, Fundación Cardiovascular de Colombia, Santander, Colombia.
authors.forename: Alba
authors.initials: A
authors.lastname: Ramirez-Sarmiento
authors.affiliation: Pulmonology Department, Hospital Clínic i Provincial de Barcelona (ICT), CIBERES, IDIBAPS, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Torralba
authors.affiliation: Facultat de Ciències de la Salut Blanquerna, Universitat Ramol Llull, Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Vilaró
authors.affiliation: Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Gimeno-Santos
authors.affiliation: Pulmonology Department, Hospital del Mar, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Pompeu Fabra (UPF), CIBERES, (ISCIII), Barcelona, Spain.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Gea
authors.affiliation: Pulmonology Department, Hospital del Mar, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Pompeu Fabra (UPF), CIBERES, (ISCIII), Barcelona, Spain.|Pulmonology Department, Fundación Cardiovascular de Colombia, Santander, Colombia.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Orozco-Levi
authors.affiliation: Pulmonology Department, Hospital Clínic i Provincial de Barcelona (ICT), CIBERES, IDIBAPS, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Roca
authors.affiliation: Physical Medicine and Rehabilitation Department, Parc de Salut Mar (Hospital del Mar - Hospital de l'Esperança), Rehabilitation Research Group, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Autònoma de Barcelona, Universitat Internacional de Catalunya, Barcelona, Catalonia, Spain.
authors.forename: Ester
authors.initials: E
authors.lastname: Marco
mesh_terms: D000367:Age Factors; D000368:Aged; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy / Q000009:adverse effects / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology* / Q000534:rehabilitation*; D016896:Treatment Outcome
keywords: COPD; autonomic function; continuous training; exercise; interval training