The Role of Resistance Training Dosing on Pain and Quality of Life in Individuals with Knee Osteoarthritis: A Systematic Review

PURPOSE: To determine whether resistance training effects pain and quality of life in individuals with knee osteoarthritis (OA), and whether or not a dose-response relationship exists. Secondly, we will investigate if the effects of resistance training are influenced by KL grade or location of OA (tibiofemoral and/or patellofemoral). METHODS: A systematic literature search of three electronic databases (PubMed, CINAHL, and EMBase) was performed for English studies to identify RTCs comparing resistance interventions with no intervention or education in knee OA and reporting changes in pain and physical function. Articles meeting inclusion criteria were assessed independently by two reviewers for methodological quality using the CONSORT 2010 scale and bias assessed by the Cochrane Collaboration’s tool for assessing risk of bias. RESULTS: Four hundred and sixty-nine studies were found in the initial search. Fourteen were included for analysis after screening. Thirteen trials were rated with high methodological quality based on the CONSORT scoring system. One study was excluded due to poor CONSORT score (9). Thirteen eligible trials with 1,521 participants were therefore included in the subsequent analysis. The average CONSORT quality score was 20.3 (range 17 to 24.5). Evidence from eleven studies revealed resistance training significantly improved pain and/ or quality of life. No trends were identified with maximum strength, and frequency of exercise sets or repetitions, and thus trends between strength training outcomes and location or KL grade of knee OA were unable to be evaluated. CONCLUSION: This systematic review suggests that resistance training improves pain and quality of life for patients with knee OA, but specific optimal dosing strategies remain unknown. Further high quality prospective studies with homogenous populations and interventions aimed to investigate precise dosing parameters are needed.