Abstract
Background/Objectives: Pain is the most common symptom of osteoarthritis (OA), and it leads to functional decline, such as decreased mobility and limitations in activities of daily living, which leads to difficulties in social participation, increased social isolation, and economic burden. Muscle weakness can be a cause of OA symptoms. The purpose was to analyze the effects of resistance training on improving pain, strength, and function in OA and to analyze the effects by intervention duration and joint. Methods: The study search was conducted on 14 September 2024, and the period of study inclusion covered studies available in the databases from their inception to the search date. The databases used were PubMed, CHINAL, Cochrane Library, and Embase. Inclusion criteria were studies that targeted OA and compared a resistance training intervention with a no resistance training intervention group and measured pain, strength, and function. Subgroup analysis was used to analyze the effects by intervention duration (4 weeks or less, 5 to 8 weeks, 9 weeks or more) and joint (knee, hip). Results: A total of 27 studies included 1712 subjects, and significant improvements were observed in pain (SMD: -0.48, CI: -0.58~-0.37, I(2): 45%), strength (SMD: 0.4, CI: 0.32~0.47, I(2): 0%), and function (SMD: -0.56, CI: -0.65~-0.47, I(2): 30%). In the effects by intervention duration, both pain and strength showed significant improvements, but no effect on function was observed for less than 4 weeks. For effects by joint, both the knee and hip showed significant improvements. Conclusions: Resistance training was effective in improving pain, strength, and function in patients with knee and hip OA.