Time-based physical activity interventions for weight loss: a randomized trial

Evidence-Based Eating Patterns and Behavior Changes to Limit Excessive Gestational Weight Gain: A Scoping Review

BACKGROUND

International prenatal care guidelines set a standard for clinicians to discuss gestational weight gain with their patients along with the complications associated with prepregnancy obesity and excessive gestational weight gain. Clinicians often lack evidence-based eating, nutrition, and activity strategies to share with patients.

METHODS

This systematic review aimed to find eating patterns and behaviors that could be used safely during pregnancy to limit excessive gestational weight gain. PubMed, MEDLINE, and Web of Science were searched for research or systematic reviews performed in the United States or Canada and published in English from 2013 to 2023. Keyword search terms included weight, manage, behavior, strategy, strategies, gestational weight gain, and nutrition. Excluded research used pediatric or adolescent populations, restrictive diets, such as no carbohydrate or no fat diets, fasting, bariatric surgery, weight loss medications, private industry or profit-earning programs using food brands, or specific diet programs.

RESULTS

A total of 844 abstracts were retrieved, with 103 full-text studies reviewed. Behaviors had to be useful for maintaining a healthy gestational weight gain and had to be safe for use during pregnancy. Behaviors useful during pregnancy included meal planning, home meal preparation, portion control, using diets such as the Mediterranean diet, the low-glycemic index diet, and the Dietary Approaches to Stop Hypertension diet (DASH), regular physical activity, sleeping 6-7 h a night, mindful eating, intuitive eating, and regular seif-weighing.

CONCLUSION

The evidence-based strategies outlined in this review are safe for use during pregnancy and can assist patients in avoiding excessive gestational weight gain while maintaining the nutrition needed for healthy fetal growth.

Effects of Different Low-Intensity Exercise Types on Duration, Energy Expenditure and Perceived Exertion in Obese Individuals

Physical exercise is a common strategy in overweight and obesity management. Exercise type, intensity, duration, energy expenditure and the rate of perceived exertion (RPE) are the essential determinants of exercise efficiency. The purpose of the present study was to compare continuous and intermittent exercises targeted at the maximal fat oxidation intensity (FAT max) in obese individuals. Ten obese males (BMI > 30 kg/m2; age: 19 to 35 years) who maintained a sedentary lifestyle were recruited for this study to perform three separate exhaustive exercises: a continuous exercise at FAT max (CON), an intermittent exercise that alternates two minutes at FAT max −10% with one minute at FAT max +20% (INT½), and a second intermittent exercise that alternates four minutes at FAT max −10% with one minute at FAT max +40% (INT¼). The duration of the INT¼ exercise (65.1 min ± 13.4) was significantly longer than that of the CON exercise (55.4 min ± 6.0). No significant difference in the total amount of energy expenditure was observed across the three types of exercise (CON: 372 Kcal ± 98.2, INT¼: 398 Kcal ± 145.5, INT½: 374.4 Kcal ± 116.1). The fat oxidation rate after 45 min during the INT exercises (INT¼: 93.0 ± 19.1 mg/min, INT½: 71.1 ± 15.6 mg/min) was significantly higher than that of the CON exercise (36.1 ± 12.2 mg/min). The CON exercise was less well tolerated. The rate of perceived exertion (RPE) at the end of the CON (15.8 ± 2) was significantly higher than that of the INT exercises (13.5 ± 2 for the INT¼ and 13.1 ± 1.8 for the INT½). The INT exercises were more efficient in terms of duration, fat oxidation and RPE.

Describing the Weight-Reduced State: Physiology, Behavior, and Interventions

Although many persons with obesity can lose weight by lifestyle (diet and physical activity) therapy, successful long-term weight loss is difficult to achieve, and most people who lose weight regain their lost weight over time. The neurohormonal, physiological, and behavioral factors that promote weight recidivism are unclear and complex. The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop in June 2019, titled "The Physiology of the Weight-Reduced State," to explore the mechanisms and integrative physiology of adaptations in appetite, energy expenditure, and thermogenesis that occur in the weight-reduced state and that may oppose weight-loss maintenance. The proceedings from the first session of this workshop are presented here. Drs. Michael Rosenbaum, Kevin Hall, and Rudolph Leibel discussed the physiological factors that contribute to weight regain; Dr. Michael Lowe discussed the biobehavioral issues involved in weight-loss maintenance; Dr. John Jakicic discussed the influence of physical activity on long-term weight-loss maintenance; and Dr. Louis Aronne discussed the ability of drug therapy to maintain weight loss.

Identifying Predictors of the Visceral Fat Index in the Obese and Overweight Population to Manage Obesity: A Randomized Intervention Study

INTRODUCTION

Nowadays, obesity is one of the main causes of death and disability. In recent years, it has been shown that the excess and distribution of body fat increases morbidity, with excess visceral fat being the most important factor that triggers pathologies. Thus, estimation of visceral fat makes it possible to identify patients with a higher cardiovascular risk, aiding the management of obesity. The main objective of the study was to identify predictors of the visceral fat index through a lifestyle intervention and to observe the effect of the intervention on dietary habits and functional capacity.

METHODS

A randomized intervention, parallel-group study was made. This study included 97 obese and overweight people (control group, n = 48; experimental group, n = 49) with a low socioeconomic status in an 8-month lifestyle intervention. Anthropometric, fitness and nutritional tests were assessed.

RESULTS

It was found that being female, eating the recommended daily portions of fruit, gaining strength in the legs and gaining flexibility are factors predictive of a lower visceral fat index. Age over 45 years and eating the recommended weekly portions of cereals and meats, fat and processed meats increases the visceral fat index after a lifestyle intervention. There were changes in the visceral fat index and in the different physical condition variables, but not in eating habits.

CONCLUSION

A multicomponent lifestyle intervention reduces the visceral fat index; age over 45 and consuming cereals and meat increases the visceral fat index.

The Impact of Timing of Exercise Initiation on Weight Loss: An 18-Month Randomized Clinical Trial

OBJECTIVE

This study aimed to evaluate the impact of timing of exercise initiation on weight loss within a behavioral weight loss program.

METHODS

Adults with overweight or obesity (N = 170; age 18-55 years; BMI 25-42 kg/m² ; 83.5% women) were enrolled in an 18-month behavioral weight loss program consisting of a reduced-calorie diet, exercise, and group-based support. The standard group (STD) received a supervised exercise program (progressing to 300 min/wk of moderate-intensity aerobic exercise) during months 0 to 6. The sequential group (SEQ) was asked to refrain from changing exercise during months 0 to 6 and received the supervised exercise program during months 7 to 12. On completion of supervised exercise, both groups were instructed to continue 300 min/wk of moderate-intensity exercise for the study duration.

RESULTS

At 6 months, the STD group exhibited greater reductions in body weight (-8.7 ± 0.7 kg) compared with the SEQ group (-6.9 ± 0.6 kg; P = 0.047). Between 6 and 18 months, the STD group regained more weight (2.5 ± 0.8 kg vs. 0.0 ± 0.8 kg; P = 0.02). At 18 months, there were no between-group differences in changes in weight (STD: -6.9 ± 1.2 kg; SEQ: -7.9 ± 1.2 kg), fat mass, lean mass, physical activity, or attrition.

CONCLUSIONS

Both immediate and delayed exercise initiation within a behavioral weight loss program resulted in clinically meaningful weight loss at 18 months. Thus, timing of exercise initiation can be personalized based on patient preference.

Response to a standard behavioral weight loss intervention by age of onset of obesity

Background

The purpose of this study was to examine weight loss, physical activity, fitness and diet changes in response to a standard behavioral weight loss intervention in adults with self‐reported juvenile onset (n = 61) or adult onset (n = 116) obesity.

Methods

Participants (n = 177; 43.0 ± 8.6 years; body mass index [BMI] = 33.0 ± 3.4 kg m⁻²) engaged in an 18‐month standard behavioral weight loss intervention. Participants were randomized into three different intervention groups as part of the larger parent trial. BMI, physical activity, fitness and diet were assessed at baseline, 6, 12 and 18 months. Separate adjusted mixed models were constructed using SAS version 9.4 (SAS Institute, Cary, NC).

Results

There was significant weight loss, increased physical activity, improved fitness and reduced caloric intake over time (p < 0.001). There were no significant differences in these outcome variables by obesity onset group. However, there was a significant group by time interaction for fitness (p = 0.001), with the adult onset making significantly greater gains in fitness from baseline to 6 months (p < 0.001); however, this difference was no longer present at 12 or 18 months.

Conclusions

With the exception of fitness at 6 months, weight loss, physical activity and diet did not differ between juvenile onset and adult onset participants, suggesting that those with juvenile onset obesity are equally responsive to a standard behavioral weight loss intervention in adulthood.

Short-term weight loss with diet and physical activity in young adults: The IDEA study

OBJECTIVE

This study examined the effect of a behavioral weight loss intervention (BWLI) on young adults (age = 18-35 years).

METHODS

Participants (N = 470) enrolled in a 6-month BWLI that included weekly group sessions, a prescribed energy-restricted diet, and moderate to vigorous physical activity (MVPA). Assessments included weight, body composition, fitness, lipids, glucose, insulin, resting blood pressure and heart rate, physical activity, and dietary intake. Data are presented as median [25th, 75th percentiles].

RESULTS

Retention was 90% (N = 424; age: 30.9 [27.8, 33.7] years; BMI: 31.2 [28.4, 34.3] kg m(-2) ). Participants completed 87.5% [76.1%, 95.5%] of scheduled intervention contacts. Weight and body fat decreased while fitness increased (P < 0.0001). MVPA in bouts ≥10 min increased (P < 0.0001), though total MVPA did not change significantly. Sedentary time decreased (P = 0.03). Energy and percent fat intake decreased, while percent carbohydrate and protein intake increased (P < 0.0001). Systolic and diastolic blood pressure, total cholesterol, LDL cholesterol, triglycerides, glucose, and insulin decreased (P < 0.0001).

CONCLUSIONS

A 6-month BWLI produced favorable changes in dietary intake and physical activity and elicited favorable changes in weight and other health outcomes in young adults. MVPA performed in bouts of ≥10 min was associated with greater weight loss, but sedentary behavior was not.