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The impact of Dietary Weight loss, Aerobic Exercise, and Daylong Movement on Social Cognitive Mediators of Long-term Weight loss.
Fanning, J, Nicklas, B, Furlipa, J, Rejeski, WJ
Journal of behavioral medicine. 2023;46(3):499-508
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Plain language summary
Obesity in older adults predisposes individuals to physical disability, a host of chronic diseases, and premature mortality. A strong body of evidence indicates that well-designed structured exercise interventions increase older adults’ self-efficacy and satisfaction with their physical functioning, and these are important social cognitive outcomes closely linked with quality of life and health behaviour change. The main aim of this study was to investigate changes in walking self-efficacy and satisfaction after the 6-month intensive phase of the intervention. This study was a secondary analysis of the Empowered with Movement to Prevent Obesity and Weight Regain (EMPOWER) study, which was an 18-month, three-group, single-blind randomised trial. A total of 183 participants were randomly assigned to one of the three treatment arms: weight loss + structured exercise (WL+EX), WL+ sitting less and moving more across the day (SL), or WL+EX+SL. Results showed that: - participants demonstrated improvements in self-efficacy and satisfaction following the 6-month intervention weight loss and physical activity intervention. - participants who received an exercise intervention focused on sustained walking demonstrated significantly better self-efficacy for walking relative to those who did not (WL+SL). - both WL+EX and WL+EX+SL regressed to baseline levels of self-efficacy for walking by month 18, only WL+SL did not significantly decrease self-efficacy scores, sustaining a significant increase over baseline. Authors conclude that programs focused on daylong movement may contribute to improved self-efficacy and satisfaction. Thus, health promotion professionals should demonstrate flexibility in the ways in which physical activity is prescribed for older adults since not everyone resonates with traditional structured exercise.
Abstract
This report contrasts the impact of a dietary weight loss intervention (WL) paired with aerobic exercise (EX) and/or sitting less and moving throughout the day (SL) on self-efficacy for walking (hereafter walking self-efficacy) and satisfaction with physical functioning (hereafter satisfaction). Additional analyses examined dose-response associations between change in weight and changes in these key outcomes. Older adults (N = 112; age = 70.21[Formula: see text]4.43) were randomized to 6 months of WL+EX, WL+SL, or WL+EX+SL followed by a 12-month maintenance period. All groups reported increases in walking self-efficacy at month 6 with greater improvements in WL+EX and WL + EX+SL. Only WL+SL demonstrated improved walking self-efficacy at month 18. All conditions demonstrated improved satisfaction scores at both time points. Changes in walking self-efficacy and satisfaction were negatively associated with change in weight over the 6-month intervention and after the maintenance period. These results support the utility of WL + SL for improving key social cognitive outcomes in aging.
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The consequences of exercise-induced weight loss on food reinforcement. A randomized controlled trial.
Flack, KD, Hays, HM, Moreland, J
PloS one. 2020;15(6):e0234692
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Exercise is a long-standing remedy for nearly all of obesity’s comorbidities and often recommended as an economical and health-promoting option for weight loss and weight loss maintenance. The aim of this study was to investigate the effect of exercise on food reinforcement (reward-driven feeding), and to examine whether changes in body composition would be correlated with changes in food reinforcement. This study is randomized controlled trial with a total of 52 participants aged 18 to 40 years. Participants were randomly assigned to one of the three groups (six exercise sessions per week, two sessions per week, and sedentary control). Results indicate that there is great variability in individuals’ change in food reinforcement after a 12-week aerobic exercise intervention. Furthermore, those who did increase their food reinforcement were also those who lost the greatest amount of fat-free mass post-intervention. Authors conclude that preventing the loss of fat-free mass may be a valuable piece to a weight loss programme (with resistance training or dietary protein intake as adjunct therapy).
Abstract
BACKGROUND Obesity remains a primary threat to the health of most Americans, with over 66% considered overweight or obese with a body mass index (BMI) of 25 kg/m2 or greater. A common treatment option many believe to be effective, and therefore turn to, is exercise. However, the amount of weight loss from exercise training is often disappointingly less than expected with greater amounts of exercise not always promoting greater weight loss. Increases in energy intake have been prescribed as the primary reason for this lack of weight loss success with exercise. Research has mostly focused on alterations in hormonal mediators of appetite (e.g.: ghrelin, peptide YY, GLP-1, pancreatic polypeptide, and leptin) that may increase hunger and/or reduce satiety to promote greater energy intake with exercise training. A less understood mechanism that may be working to increase energy intake with exercise is reward-driven feeding, a strong predictor of energy intake and weight status but rarely analyzed in the context of exercise. DESIGN Sedentary men and women (BMI: 25-35 kg/m2, N = 52) were randomized into parallel aerobic exercise training groups partaking in either two or six exercise sessions/week, or sedentary control for 12 weeks. METHODS The reinforcing value of food was measured by an operant responding progressive ratio schedule task (the behavioral choice task) to determine how much work participants were willing to perform for access to a healthy food option relative to a less healthy food option before and after the exercise intervention. Body composition and resting energy expenditure were assessed via DXA and indirect calorimetry, respectively, at baseline and post testing. RESULTS Changes in fat-free mass predicted the change in total amount of operant responding for food (healthy and unhealthy). There were no correlations between changes in the reinforcing value of one type of food (healthy vs unhealthy) to changes in body composition. CONCLUSION In support of previous work, reductions in fat-free mass resulting from an aerobic exercise intervention aimed at weight loss plays an important role in energy balance regulation by increasing operant responding for food.