title: Effects of resistance training on arterial stiffness: a meta-analysis.
abstract: BACKGROUND
  Regular aerobic exercise prevents and reverses arterial stiffening, but the association between resistance training and arterial stiffness is unclear.
  
  
  OBJECTIVE
  This study was performed to conduct a systematic review and meta-analysis of randomised controlled clinical trials (RCTs) assessing the associations between resistance training and changes in arterial stiffness.
  
  
  METHODS
  MEDLINE and SPORTDiscus databases were searched from January 1980 through to April 2011. RCTs evaluating the ability of resistance training to increase arterial stiffness in comparison with a control group were included in the meta-analysis. Two independent reviewers extracted data and assessed the quality of the included studies. Data from 185 reports of eight RCTs (193 participants) were included. Pooled mean differences in arterial stiffness indices (carotid arterial β stiffness and pulse wave velocity (PWV)) between intervention and control groups were calculated using a random-effects model.
  
  
  RESULTS
  The overall association of resistance training versus control with relative changes in carotid β index or PWV (eight studies; 193 participants) was 10.7% (95% CI 3.4% to 18.0%; I(2), 89%; heterogeneity, p<0.001). Five studies indicated that resistance training in young subjects (n=115) was significantly associated with an increase in stiffness index of 14.3% (95% CI 8.5% to 20.1%; I(2), 71%; heterogeneity, p<0.001) compared with controls. However, three studies showed that resistance training in middle-aged subjects (n=78) was not associated with changes in arterial stiffness. In addition, although high-intensity resistance training (n=87) was significantly associated with an increase in stiffness of 11.6%, moderate-intensity resistance training (n=106) showed no such association.
  
  
  CONCLUSIONS
  High-intensity resistance training is associated with increased arterial stiffness in young subjects with low baseline levels of arterial stiffness.
authors.affiliation: Department of Health Promotion and Exercise, National Institute of Health and Nutrition, Toyama 1-23-1, Shinjuku, Tokyo 162-8636, Japan. miyachi@nih.go.jp
authors.forename: Motohiko
authors.initials: M
authors.lastname: Miyachi
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D055070:Resistance Training; D059289:Vascular Stiffness / Q000502:physiology*