The most prevalent form of arthritis and a leading cause of disability in adults is osteoarthritis. Knee osteoarthritis symptoms increase with age, exacerbating the associated problems concerning mobility, independence, quality of life, and participation in social life. Overusing their knees in adults can worsen joint health and knee osteoarthritis, but the less they move their knees, the muscles surrounding the knee can become weak. It is essential to determine an exercise program that helps the knee cope with daily life activities. Professionals recommend strength training for individuals with knee osteoarthritis. However, a critical problem with strength training is the determination of an optimal level of intensity.

Previous researches in strength training for patients with osteoarthritis have had limitations such as using training intensities lower than those prescribed by practice standards and using short-duration treatments lasting between 6 and 24 weeks. Wake Forest University scientists Dr. Stephen P. Messier, Dr. Barbara J. Nicklas, and Dr. Paul DeVita at East Carolina University conducted a randomized controlled trial.  Their study assessed whether high-intensity strength training lowered pain and decreased knee joint compressive more than low-intensity strength training and participation at a general health workshop among patients with knee osteoarthritis. Their research work is published in The Journal of the American Medical Association.

Researchers reported no significant difference in knee pain or knee compressive forces during walking between the three groups at 18 months. Secondary outcomes results demonstrated that the low-intensity group had substantially lower knee pain and better function than the high-intensity group at the 6-month (short-term) follow-up. In addition, at six months, there were no significant differences in knee joint compressive forces between groups.

According to the research results, the average walking distances of the participants were similar at the 6th and 18th months. However, the mean distance walk in the high-intensity group was significantly less than in the low-intensity group at six months. Although there was no critical difference in mean walking distances between groups in the 18th month, the lowest distance belonged to the high-intensity group.

Knee extensor strength reported the effectiveness for reduced pain and improved function in osteoarthritis knees. Researchers have shown knee extensor means power was more significant in the high-intensity group than in the control group at 18 months but was not more effective than in the low-intensity group.

In summary, this paper has shown no significant difference between high-intensity strength training, low-intensity strength training, or attention control groups in reducing knee pain or knee joint compression forces at 18 months in patients with knee osteoarthritis. On this basis, this study concludes that it does not support the use of high-intensity strength training instead of low-intensity strength training or attention control in the rehabilitation of adults with osteoarthritis.

Journal Reference

Messier, S. P., Mihalko, S. L., Beavers, D. P., Nicklas, B. J., DeVita, P., Carr, J. J., & Loeser, R. F. (2021). Effect of High-Intensity Strength Training on Knee Pain and Knee Joint Compressive Forces Among Adults With Knee Osteoarthritis: The START Randomized Clinical Trial. JAMA325(7), 646-657.

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