Association Between Prescribed Dosage of Resistance Exercise and Change in Pain and Physical Function in Knee Osteoarthritis: A Systematic Review With Meta-Regression

Objective: To assess whether there is an association between total prescribed dosage of resistance exercise (volume, frequency, intensity, and duration) and change in pain and physical function in individuals with knee osteoarthritis (OA). Method: A systematic review with meta-regression was conducted, searching MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials until December 11, 2024. We included randomised controlled trials that compared resistance exercise for knee OA with non-exercise interventions. Meta-regression examined the association between total prescribed exercise dosage (volume × frequency × intensity × duration of the intervention) and standardised mean differences (SMDs) for change in pain and physical function. Covariates were included to attempt to reduce between-study heterogeneity. Results: Analysis of 14 trials (N = 1274) found no association between total prescribed resistance exercise dosage and changes in pain (slope coefficient: < 0.01 on a 0–100 scale [95% CI: < − 0.01 to < 0.01]; p = 0.18) or physical function (slope coefficient: < 0.01 on a 0–100 scale [95% CI: < − 0.01 to < 0.01]; p = 0.15). Heterogeneity was substantial (I² = 73%–97%) and many trials were of unclear/high risk of bias. Conclusion: No association was found between the total prescribed dosage of resistance exercise and changes in pain or function in individuals with knee OA. However, due to the limited number of trials, high heterogeneity, and overall low quality of studies, findings should be interpreted with caution.