Effect of a Physical Activity Promoting Program Based on the IMB Model on Obese-Metabolic Health Outcomes among Obese Older Adults with Knee Osteoarthritis

Abstract

PURPOSE: This study examined the effects of a physical activity promoting program based on the Information-Motivation-Behavioral Skills (IMB) model on physical activity and health outcomes among obese older adults with knee osteoarthritis. METHODS: This study utilized a randomized controlled trial with a convenience sample of 75 obese older adults with knee osteoarthritis in a university hospital. The older adults in the intervention group participated in a 12-week program involving weekly group sessions and monitoring calls with education booklets and video clips for exercise dances, while those in the control group received an usual care. Outcomes were measured using self-report questionnaires, anthropometrics, and blood analyses. The intervention effects were analyzed using Mann-Whitney U test and ANCOVA. RESULTS: The mean age of participants was 74.9 years with 84.0% women. The intervention group at 12 weeks showed significantly greater improvements in self-efficacy for physical activity (F=81.92, p<.001), physical activity amounts (Z=-2.21, p=.044), knee joint function (F=15.88, p<.001), and health-related quality of life (F=14.89, p<.001) compared to the control group. Among obese-metabolic outcomes, the intervention group at 12 weeks showed a significant decrease in visceral fat mass (F=7.57, p=.008) and improvement in high-density level cholesterol (F=9.51, p=.003) compared to the control group. CONCLUSION: Study findings support the need for an IMB based physical activity program for promoting physical activity, knee function and health outcomes in obese older adults with knee osteoarthritis. Longitudinal studies are warranted to confirm the persistence of obese-metabolic effects in clinical settings.