ObjectiveTo examine the long-term effects of exercise modality during weight loss on body composition and associations between body composition and physical function changes.Methods249 older adults (66.9±4.7 years, 71% women, 32% African American, BMI: 34.4±3.7 kg/m2) were randomized to weight loss (WL; n=82), WL plus aerobic training (WL+AT; n=86), or WL plus resistance training (WL+RT; n=81) for 18-months. DXA-acquired body composition, 400-m walk time, and knee extensor strength were measured at baseline, 6-, and 18-months.ResultsTotal body mass loss was enhanced when WL was combined with exercise (WL: −5.7±0.7 kg, WL+AT: −8.5±0.7 kg, WL+RT: −8.7±0.7 kg; p<0.01). Total body fat mass loss was significantly greater in WL+AT (−6.8±0.6 kg, −16.4%) and WL+RT (−7.8±0.5 kg, −19.0%) than WL (−4.8±0.6 kg, −10.9%); both p<0.01. Lean mass loss was greatest in WL+AT (−1.6±0.3 kg, −3.1%) compared to WL+RT (−0.8±0.3 kg, −1.5%) or WL (−1.0±0.3 kg; −2.0%); both p≤0.02). Change in 400-m walk time was associated with change in fat mass (β/SD=+6.1 sec; p<0.01), while change in knee extensor strength was associated with change in lean mass (β/SD=+1.6 Nm; p<0.01).ConclusionsWL+RT results in less lean mass lost than WL+AT; WL plus exercise yields greater fat mass loss than WL alone.

Objective This study determined whether adding a self-regulatory intervention (SRI) focused on self-monitoring of spontaneous physical activity and sedentary behavior to a standard weight loss intervention improved maintenance of lost weight. Design and Methods Older (65–79 yrs), obese (BMI=30–40 kg/m2) adults (n=48) were randomized to a five-month weight loss intervention involving a hypocaloric diet (DIET) and aerobic exercise (EX) with or without the SRI to promote spontaneous physical activity and decrease sedentary behavior (SRI+DIET+EX compared to DIET+EX). Following the weight loss phase, both groups transitioned to self-selected diet and exercise behavior during a 5-month follow-up. Throughout the 10-months, the SRI+DIET+EX group utilized real-time accelerometer feedback for self-monitoring. Results There was an overall group by time effect of the SRI (P < 0.01); DIET+EX lost less weight and regained more weight than SRI+DIET+EX. The average weight regain during follow-up was 1.3 kg less in the SRI+DIET+EX group. Individuals in this group maintained ~10% lower weight than baseline compared to those in the DIET+EX group whom maintained ~5% lower weight than baseline. Conclusions Addition of a self-regulatory intervention, designed to increase spontaneous physical activity and decrease sedentary behavior, to a standard weight loss intervention enhances successful maintenance of lost weight.

Background The study objectives were to determine (a) the effects of group-mediated cognitive–behavioral interventions on change in performance self-efficacy, satisfaction with function, and with appearance among older, overweight/obese adults in poor cardiovascular health and (b) whether self-efficacy mediated change in 400-m walk time. Methods This translational, randomized controlled trial of physical activity and weight loss was conducted within community Cooperative Extension Centers. Participants were randomized to three intervention arms: Physical Activity, Weight Loss+ Physical Activity, or a Successful Aging education control. Results Across 18 months, the Weight Loss+Physical Activity intervention demonstrated greater improvements in self-efficacy, satisfaction with function, and appearance versus other trial arms. Physical Activity intervention participants also experienced significant improvements in self-efficacy and satisfaction with function versus those in Successful Aging. Self-efficacy mediated 400-m walk time at 18 months. Conclusions Both group-mediated cognitive–behavioral interventions yielded desirable improvements in social cognitions and preserved mobility improvements post-intervention.

A complication of cardiovascular disease (CVD) and the metabolic syndrome (MetS) among older adults is loss of mobility. The American Heart Association has identified weight management as a core component of secondary prevention programs for CVD and is an important risk factor for physical disability. The American Society for Nutrition and the Obesity Society have highlighted the need for long-term randomized clinical trials to evaluate the independent and additive effects of diet-induced weight loss (WL) and physical activity in older persons on outcomes such as mobility, muscle function, and obesity related diseases. Here we describe the rationale, design, and methods of a translational study, the Cooperative Lifestyle Intervention Program-II (CLIP-II). CLIP-II will randomize 252 obese, older adults with CVD or MetS to a weight loss only treatment (WL), aerobic exercise training (AT)+WL, or resistance exercise training (RT)+WL for 18 months. The dual primary outcomes are mobility and knee extensor strength. The interventions will be delivered by YMCA community partners with our staff as trainers and advisers. This study will provide the first large scale trial to evaluate the effects of diet-induced WL on mobility in obese, older adults with CVD or MetS as compared to WL combined with two different modes of physical activity (AT and RT). Because uncertainty exists about the best approach for promoting WL in older adults due to concerns with the loss of lean mass, the design also permits a contrast between AT+WL and RT+WL on muscle strength.

There is a need to identify evidenced-based obesity treatments that are effective in maintaining lost weight. Weight loss results in reductions in energy expenditure, including spontaneous physical activity (SPA) which is defined as energy expenditure resulting primarily from unstructured mobility-related activities that occur during daily life. To date, there is little research, especially randomized, controlled trials, testing strategies that can be adopted and sustained to prevent declines in SPA that occur with weight loss. Self-monitoring is a successful behavioral strategy to facilitate behavior change, so a provocative question is whether monitoring SPA-related energy expenditure would override these reductions in SPA, and slow weight regain. This study is a randomized trial in older, obese men and women designed to test the hypothesis that adding a self-regulatory intervention (SRI), focused around self-monitoring of SPA, to a weight loss intervention will result in less weight and fat mass regain following weight loss than a comparable intervention that lacks this self-regulatory behavioral strategy. Participants (n=72) are randomized to a 5-month weight loss intervention with or without the addition of a behavioral component that includes an innovative approach to promoting increased SPA. Both groups then transition to self-selected diet and exercise behavior for a 5-month follow-up. Throughout the 10-month period, the SRI group is provided with an intervention designed to promote a SPA level that is equal to or greater than each individual's baseline SPA level, allowing us to isolate the effects of the SPA self-regulatory intervention component on weight and fat mass regain.