title: Walking training at the heart rate of pain threshold improves cardiovascular function and autonomic regulation in intermittent claudication: A randomized controlled trial.
abstract: OBJECTIVE
  This study investigated the effects of walking training (WT) on cardiovascular function and autonomic regulation in patents with intermittent claudication (IC).
  
  
  METHODS
  Randomized controlled trial.
  
  
  METHODS
  Forty-two male patients with IC (≥50years) were randomly allocated into two groups: control (CG, n=20, 30min of stretching exercises) and WT (WTG, n=22, 15 bouts of 2min of walking interpolated by 2min of upright rest-walking intensity was set at the heart rate of pain threshold). Both interventions were performed twice/week for 12 weeks. Walking capacity (maximal treadmill test), blood pressure (auscultatory), cardiac output (CO2rebreathing), heart rate (ECG), stroke volume, systemic vascular resistance, forearm and calf vascular resistance (plethysmography), and low (LF) and high frequency (HF) components of heart rate variability and spontaneous baroreflex sensitivity were measured at baseline and after 12 weeks of the study.
  
  
  RESULTS
  WT increased total walking distance (+302±85m, p=0.001) and spontaneous baroreflex sensitivity (+2.13±1.07ms/mmHg, p=0.02). Additionally, at rest, WT decreased systolic and mean blood pressures (-10±3 and -5±2mmHg, p=0.001 and p=0.01, respectively), cardiac output (-0.37±0.24l/min, p=0.03), heart rate (-4±2bpm, p=0.001), forearm vascular resistance (-8.5±2.8U, p=0.02) and LF/HF (-1.24±0.99, p=0.001). No change was observed in the CG.
  
  
  CONCLUSIONS
  In addition to increasing walking capacity, WT improved cardiovascular function and autonomic regulation in patients with IC.
authors.affiliation: School of Physical Education and Sport, University of São Paulo, Brazil. Electronic address: marcel_chehuen@hotmail.com.
authors.forename: Marcel
authors.initials: M
authors.lastname: Chehuen
authors.affiliation: Albert Einstein Israelite Hospital, Brazil.
authors.forename: Gabriel G
authors.initials: GG
authors.lastname: Cucato
authors.affiliation: Hospital das Clínicas, University of São Paulo, Brazil.
authors.forename: Celso Ricardo F
authors.initials: CRF
authors.lastname: Carvalho
authors.affiliation: Albert Einstein Israelite Hospital, Brazil.
authors.forename: Raphael M
authors.initials: RM
authors.lastname: Ritti-Dias
authors.affiliation: Hospital das Clínicas, University of São Paulo, Brazil.
authors.forename: Nelson
authors.initials: N
authors.lastname: Wolosker
authors.affiliation: College of Healthcare Sciences, James Cook University, Australia.
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Leicht
authors.affiliation: School of Physical Education and Sport, University of São Paulo, Brazil.
authors.forename: Cláudia Lúcia M
authors.initials: CLM
authors.lastname: Forjaz
mesh_terms: D000368:Aged; D001794:Blood Pressure; D016022:Case-Control Studies; D005080:Exercise Test / Q000379:methods*; D005081:Exercise Therapy; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007383:Intermittent Claudication / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D017288:Pain Threshold / Q000502:physiology*; D013318:Stroke Volume / Q000502:physiology; D014655:Vascular Resistance / Q000502:physiology; D016138:Walking / Q000502:physiology*
keywords: Autonomic modulation; Blood pressure; Hemodynamic; Peripheral arterial disease; Walking training