title: Exercise-induced changes in cardiovascular function after stroke: a randomized controlled trial.
abstract: OBJECTIVE
  Cardiovascular co-morbidities are prevalent after stroke, with heart disease, hypertension and impaired glucose tolerance present in the majority of cases. Exercise has the potential to mediate cardiovascular risk factors commonly present in people with stroke. This single-blinded randomized controlled trial compared the effects of high versus low intensity exercise on fitness, cardiovascular risk factors, and cardiac function after stroke.
  
  
  METHODS
  Fifty participants (age 50-80 y, >1 y post-stroke) were randomized to a high-intensity Aerobic Exercise (AE) or low-intensity non-aerobic Balance/Flexibility (BF) program (6 months, 3 60-min sessions/week). Outcomes assessed by VO2 peak (primary outcome), arterial stiffness, ambulatory capacity, hemodynamics and cardiac function using echocardiography, and lipid, glucose and homocysteine levels. Assessors were blinded to group allocation.
  
  
  RESULTS
  Twenty-three (92%) of 25 AE group participants (withdrawals unrelated to the intervention) and all BF group participants completed the program. One BF group participant experienced 2 non-injurious falls during class. No other adverse events occurred. There were no changes in VO2 peak in either group (AE 16·9±7 to 17·4±7 ml●kg(-1) ●min(-1) vs. BF 16·9±6 to 16·6±5 ml●kg(-1) ●min(-1) , P=0·45), but AE group demonstrated greater improvement in right atrial emptying fraction (AE 30±22 to 37±22% vs. BF 35±20 to 31±20%, P=0·04). Both groups demonstrated improvements in lipid profiles, glucose and homocysteine levels, and ambulatory capacity (P<0·04).
  
  
  CONCLUSIONS
  This was the first study to examine the effects of aerobic exercise after stroke on cardiovascular hemodynamics. High-intensity exercise improved right-sided function and early myocardial relaxation. Low-intensity exercise may also benefit plasma lipid, glucose and inflammatory markers, and ambulatory capacity. This study is an important step towards understanding mechanisms by which exercise may reduce cardiovascular risk and function.
authors.affiliation: Faculty of Medicine, Department of Physical Therapy, Vancouver Coastal Health, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Ada
authors.initials: A
authors.lastname: Tang
authors.forename: Janice J
authors.initials: JJ
authors.lastname: Eng
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Krassioukov
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Madden
authors.forename: Azam
authors.initials: A
authors.lastname: Mohammadi
authors.forename: Michael Y C
authors.initials: MY
authors.lastname: Tsang
authors.forename: Teresa S M
authors.initials: TS
authors.lastname: Tsang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D002320:Cardiovascular Physiological Phenomena; D015150:Echocardiography, Doppler; D015444:Exercise / Q000502:physiology; D005080:Exercise Test; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016037:Single-Blind Method; D020521:Stroke / Q000503:physiopathology*; D000071939:Stroke Rehabilitation; D059289:Vascular Stiffness / Q000502:physiology; D016138:Walking / Q000502:physiology
chemical_list: D015415:Biomarkers
keywords: clinical trial; exercise; rehabilitation; risk factors; sonography; stroke