title: Efficacy of strengthening or aerobic exercise on pain relief in people with knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials.
abstract: OBJECTIVE
  We performed a systematic review and meta-analysis of randomized controlled trials to investigate the differences in the efficacies between strengthening and aerobic exercises for pain relief in people with knee osteoarthritis.
  
  
  METHODS
  This search was applied to Medline, Cochrane Central Register of Controlled Trials, the Physiotherapy Evidence Database, and the Cumulative Index to Nursing and Allied Health Literature. All literature published from each source's earliest date to March 2013 was included.
  
  
  METHODS
  Trials comparing the effects of exercise intervention with those of either non-intervention or psycho-educational intervention were collected. Meta-analysis was performed for trials in which therapeutic exercise was carried out with more than three sessions per week up to eight weeks, for pain in people with knee osteoarthritis. All trials were categorised into three subgroups (non-weight-bearing strengthening exercise, weight-bearing strengthening exercise, and aerobic exercise). Subgroup analyses were also performed.
  
  
  RESULTS
  Data from eight studies were integrated. Overall effect of exercise was significant with a large effect size (standardised mean difference (SMD): -0.94; 95% confidence interval -1.31 to -0.57). Subgroup analyses showed a larger SMD for non-weight-bearing strengthening exercise (-1.42 [-2.09 to -0.75]) compared with weight-bearing strengthening exercise (-0.70 [-1.05 to -0.35]), and aerobic exercise (-0.45 [-0.77 to -0.13]).
  
  
  CONCLUSIONS
  Muscle strengthening exercises with or without weight-bearing and aerobic exercises are effective for pain relief in people with knee osteoarthritis. In particular, for pain relief by short-term exercise intervention, the most effective exercise among the three types is non-weight-bearing strengthening exercise.
authors.affiliation: 1Department of Integrated Rehabilitation, Hiroshima International University, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Tanaka
authors.forename: Junya
authors.initials: J
authors.lastname: Ozawa
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Kito
authors.forename: Hideki
authors.initials: H
authors.lastname: Moriyama
mesh_terms: D016206:Databases, Bibliographic; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy / Q000379:methods*; D006801:Humans; D020370:Osteoarthritis, Knee / Q000534:rehabilitation*; D059408:Pain Management / Q000379:methods*; D016032:Randomized Controlled Trials as Topic; D055070:Resistance Training / Q000379:methods
keywords: Exercise; knee osteoarthritis; meta-analysis; pain; systematic review