This study examined the effects of dietary weight loss and exercise on the health-related quality of life (HRQL) of overweight and obese, older adults with knee osteoarthritis. A total of 316 older men and women with documented evidence of knee osteoarthritis were randomly assigned to 1 of 4 18-month interventions: dietary weight loss, exercise, dietary weight loss and exercise, or healthy lifestyle control. Measures included the SF-36 Health Survey and satisfaction with body function and appearance. Results revealed that the combined diet and exercise intervention had the most consistent, positive effect on HRQL compared with the control group; however, findings were restricted to measures of physical health or psychological outcomes that are related to the physical self.

In this 12-month trial standard exercise training was compared with a group-mediated cognitive-behavioral (GMCB) intervention with respect to effects on long-term adherence and change in physical function of older adults who were either at risk for or had cardiovascular disease. Participants (147 older men and women) were randomized to the 2 treatments. Outcomes included self-reportedphysical activity, fitness, and self-efficacy. The GMCB treatment produced greater improvements on all outcomes than did standard exercise therapy. Regardless of treatment assignment, men had more favorable change on the study outcomes than did women. Analysis of a self-regulatory process measure in the GMCB group revealed that change in barriers efficacy was related to change in physical activity and fitness. Results suggest that teaching older adults to integrate physical activity into their lives via GMCB leads to better long-term outcomes than standardized exercise therapy.

NCT02050906.

Objective. To examine changes in mobility-related self efficacy following exercise and dietary weight loss interventions in overweight and obese older adults with knee osteoarthritis (OA), and to determine if self efficacy and pain mediate the effects of the interventions on mobility task performance. Methods. The Arthritis, Diet, and Activity Promotion Trial was an 18-month, single-blind, randomized, controlled trial comparing the effects of exercise alone, dietary weight loss alone, a combination of exercise plus dietary weight loss, and a healthy lifestyle control intervention in the treatment of 316 overweight or obese older adults with symptomatic knee OA. Participants completed measures of stair-climb time and 6-minute walk distance, self efficacy for completing each mobility task, and self-reported pain at baseline, 6 months, and 18 months during the trial. Results. Mixed model analyses of covariance of baseline adjusted change in the outcomes demonstrated that the exercise ؉ dietary weight loss intervention produced greater improvements in mobility-related self efficacy (P ‫؍‬ 0.0035), stair climb (P ‫؍‬ 0.0249) and 6-minute walk performance (P ‫؍‬ 0.00031), and pain (P ‫؍‬ 0.09) when compared with the healthy lifestyle control intervention. Mediation analyses revealed that self efficacy and pain served as partial mediators of the beneficial effect of exercise ؉ dietary weight loss on stair-climb time. Conclusion. Exercise ؉ dietary weight loss results in improved mobility-related self efficacy; changes in these taskspecific control beliefs and self-reported pain serve as independent partial mediators of the beneficial effect of exercise ؉ dietary weight loss on stair-climb performance.

An acute bout of RE at 50% 1RM is associated with an immediate reduction in vigor followed by a significant decrease in SA that emerged 180 min following exercise.