Successful Weight Control Research Articles

A Pilot Study of an Acceptance-Based Behavioral Intervention for Weight Regain After Bariatric Surgery.

Tens of thousands of bariatric surgery patients each year experience sub-optimal weight loss, significant regain, or both. Weight regain can contribute to a worsening of weight-related co-morbidities, and for some, leads to secondary surgical procedures. Poor weight outcomes have been associated with decreased compliance to the recommended postoperative diet. Decreased compliance may be partially due to a lack of psychological skills necessary to engage in healthy eating behaviors over the long term, especially as the effects of surgery (on appetite, hunger, and desire for food) decrease. Many behavioral interventions do not sufficiently address these challenges and often have limited effectiveness. The study aimed to evaluate the feasibility, acceptability, and preliminary effectiveness of a novel 10-week acceptance-based behavioral intervention to stop postoperative weight regain. A sample of bariatric surgery patients (n = 11) who regained at least 10% of their maximum lost postoperative weight was recruited. All participants received the intervention, which emphasized psychological skills thought to be integral to successful weight control post-surgery. The intervention was shown to be feasible and acceptable, with 72% retention and high mean rating (4.25 out of 5.00) of program satisfaction among completers. Weight regain was stopped, and even reversed, with a mean total body weight loss of 3.58 ± 3.02% throughout the 10-week intervention. There were also significant improvements in eating-related and acceptance-related variables. These findings provide initial support for the use of a psychological acceptance-based intervention for weight regain in bariatric surgery patients.

Exposure-response model for sibutramine and placebo: suggestion for application to long-term weight-control drug development.

No wholly successful weight-control drugs have been developed to date, despite the tremendous demand. We present an exposure–response model of sibutramine mesylate that can be applied during clinical development of other weight-control drugs. Additionally, we provide a model-based evaluation of sibutramine efficacy. Data from a double-blind, randomized, placebo-controlled, multicenter study were used (N=120). Subjects in the treatment arm were initially given 8.37 mg sibutramine base daily, and those who lost <2 kg after 4 weeks’ treatment were escalated to 12.55 mg. The duration of treatment was 24 weeks. Drug concentration and body weight were measured predose and at 4 weeks, 8 weeks, and 24 weeks after treatment initiation. Exposure and response to sibutramine, including the placebo effect, were modeled using NONMEM 7.2. An asymptotic model approaching the final body weight was chosen to describe the time course of weight loss. Extent of weight loss was described successfully using a sigmoidal exposure–response relationship of the drug with a constant placebo effect in each individual. The placebo effect was influenced by subjects’ sex and baseline body mass index. Maximal weight loss was predicted to occur around 1 year after treatment initiation. The difference in mean weight loss between the sibutramine (daily 12.55 mg) and placebo groups was predicted to be 4.5% in a simulation of 1 year of treatment, with considerable overlap of prediction intervals. Our exposure–response model, which included the placebo effect, is the first example of a quantitative model that can be used to predict the efficacy of weight-control drugs. Similar approaches can help decision-making during clinical development of novel weight-loss drugs.

The Role of the Pediatrician in Primary Prevention of Obesity.

The adoption of healthful lifestyles by individuals and families can result in a reduction in many chronic diseases and conditions of which obesity is the most prevalent. Obesity prevention, in addition to treatment, is an important public health priority. This clinical report describes the rationale for pediatricians to be an integral part of the obesity-prevention effort. In addition, the 2012 Institute of Medicine report "Accelerating Progress in Obesity Prevention" includes health care providers as a crucial component of successful weight control. Research on obesity prevention in the pediatric care setting as well as evidence-informed practical approaches and targets for prevention are reviewed. Pediatricians should use a longitudinal, developmentally appropriate life-course approach to help identify children early on the path to obesity and base prevention efforts on family dynamics and reduction in high-risk dietary and activity behaviors. They should promote a diet free of sugar-sweetened beverages, of fewer foods with high caloric density, and of increased intake of fruits and vegetables. It is also important to promote a lifestyle with reduced sedentary behavior and with 60 minutes of daily moderate to vigorous physical activity. This report also identifies important gaps in evidence that need to be filled by future research.

저항성 운동과 간헐적 단식 프로그램이 신체조성에 미치는 영향

This investigation focuses on how resistance exercising and intermittent fasting affects weight, muscle quantity, body fat, body fat ratio and abdomen fat ratio. In this experiment, 44 university students of both sexes who are physically healthy without illness have participated and these research targets were randomly divided into 3 groups: one group doing both resistance exercising and intermittent fasting(exercise group, n=15), another group only doing intermittent fasting(fasting group, n=15) and the other group living daily lives(control group, n=14). Resistance exercising program during the 10 weeks was held two times a week by gradually increasing strength and intermittent fasting was 16 hours of fasting and 8 hours of eating two times per week for 10 weeks. Using bio impedance analysis, weight, muscle quantity, body fat, body fat ratio and abdomen fat ratio were measured before and after the experiment. According to the experiment, both sexes in the exercise group lost significant weight after and women in the control group significantly gained weight after the program. In the control group, both sexes clearly showed increased muscle quantity after than beforehand. For body fat ratio, both sexes in the exercise group and both sexes in the control group decreased whereas the men in control group have gained more after. In addition, abdomen fat ratio of men in the control group increased after. In conclusion, resistance exercising and intermittent fasting is effective in gaining muscle quantity and decreasing body fat ratio. This experiment can be a base line data for successful weight control later on.

저항성 운동과 간헐적 단식 프로그램이 신체조성에 미치는 영향

This investigation focuses on how resistance exercising and intermittent fasting affects weight, muscle quantity, body fat, body fat ratio and abdomen fat ratio. In this experiment, 44 university students of both sexes who are physically healthy without illness have participated and these research targets were randomly divided into 3 groups: one group doing both resistance exercising and intermittent fasting(exercise group, n=15), another group only doing intermittent fasting(fasting group, n=15) and the other group living daily lives(control group, n=14). Resistance exercising program during the 10 weeks was held two times a week by gradually increasing strength and intermittent fasting was 16 hours of fasting and 8 hours of eating two times per week for 10 weeks. Using bio impedance analysis, weight, muscle quantity, body fat, body fat ratio and abdomen fat ratio were measured before and after the experiment. According to the experiment, both sexes in the exercise group lost significant weight after and women in the control group significantly gained weight after the program. In the control group, both sexes clearly showed increased muscle quantity after than beforehand. For body fat ratio, both sexes in the exercise group and both sexes in the control group decreased whereas the men in control group have gained more after. In addition, abdomen fat ratio of men in the control group increased after. In conclusion, resistance exercising and intermittent fasting is effective in gaining muscle quantity and decreasing body fat ratio. This experiment can be a base line data for successful weight control later on.

Expert Panel Consensus for and Analysis of Key Attributes on Websites Devoted to Weight Control

Background: Obesity presents major challenges to public health in the United States. Trials of web-based interventions for weight control suggest that the Internet is a promising option for program delivery. Purpose: This study sought consensus among experts regarding critical components of successful weight control and to systematically examine popular websites for evidence of this best practice. Methods: A panel of 11 weight loss intervention researchers and program administrators rated, from an extensive list gleaned from the literature, the most important attributes necessary for successful weight loss programs. The researchers assessed the 20 highest ranking weight control websites, identified through organic search, for the presence of the attributes recommended by the panel. Results: Most of the top 20 websites provided limited information for the majority of the recommended attributes. Two websites were more popular than the remaining 18. Translation to Health Education Practice: Health education specialists must recognize the great numbers of adults and youth who regularly search the Internet for information and programs related to weight loss. Health education should collaborate with other disciplines to develop online programs based on behavior change theory and successful weight loss techniques and assure that these websites can be found through organic search engines.

Attention-deficit/hyperactivity disorder and impairment in executive functions: a barrier to weight loss in individuals with obesity?

BackgroundAn increasing body of research points to a significant association of obesity to Attention-Deficit/Hyperactivity Disorder (ADHD) and deficits in executive functions. There is also preliminary evidence suggesting that children with ADHD may be at risk of obesity in adulthood.DiscussionIn this article, we discuss the evidence showing that ADHD and/or deficits in executive functions are a barrier to a successful weight control in individuals enrolled in weight loss programs. Impairing symptoms of ADHD or deficits in executive functions may foster dysregulated eating behaviors, such as binge eating, emotionally-induced eating or eating in the absence of hunger, which, in turn, may contribute to unsuccessful weight loss. ADHD-related behaviors or neurocognitive impairment may also hamper a regular and structured physical activity. There is initial research showing that treatment of comorbid ADHD and executive functions training significantly improve the outcome of obesity in individuals with comorbid ADHD or impairment in executive functions.SummaryPreliminary evidence suggests that comorbid ADHD and deficits in executive functions are a barrier to a successful weight loss in individuals involved in obesity treatment programs. If further methodologically sound evidence confirms this relationship, screening and effectively managing comorbid ADHD and/or executive functions deficits in individuals with obesity might have the potential to reduce not only the burden of ADHD but also the obesity epidemics.

Lacking Skills to Improve Self-Control: Reward-Induced Loss of Inhibitory Control and Overeating in Restrained Eaters

Given the vital role of inhibitory control in successful weight management, the aim of this study was to examine whether inhibitory control can be increased via incentives. Specifically, participants were randomly assigned to two conditions: In the reward condition, participants could earn a monetary bonus by performing well during an inhibition task. In the control condition, participants were not rewarded for their inhibition performance. Afterwards, we measured participants' craving and food intake during a taste test. Further, dietary restraint was included as a potential moderating factor: Restrained eaters chronically attempt to limit their food intake but are generally unsuccessful in their dieting attempts, due to decreased inhibitory control abilities. Results showed that, compared to the control condition, unrestrained eaters in the reward condition significantly improved in inhibitory control, experienced less craving for food, and also consumed less calories during the taste test. Restrained eaters, in contrast, were unable to improve inhibition performance, reported higher craving for food, and consumed more calories during the taste test relative to control. Restrained eaters therefore appear incapable of applying effective inhibition strategies and would probably benefit more from extensive training procedures that gradually increase inhibitory control in order to facilitate successful weight control.

Factors Contributing to Initial Weight Loss Among Adolescents with Polycystic Ovary Syndrome

Study ObjectiveTo evaluate the impact of a multidisciplinary clinic on weight management among adolescents with PCOS. Design140 adolescent females were evaluated in a multidisciplinary PCOS clinic from March 2005 to December 2008. The team included a pediatric endocrinologist, health psychologist, dietitian, and pediatric gynecologist. 110 were diagnosed with PCOS based on the Rotterdam Criteria. Height, weight, BMI, number of subspecialists seen, use of metformin, and compliance with return visits were obtained from medical records. SettingAmerican Family Children's Hospital in Madison, Wisconsin. Participants110 adolescent females with polycystic ovary syndrome. InterventionsConsultation with a dietitian and health psychologist. Main Outcome MeasureChange in weight. ResultsThe average age at first visit was 15.9 years. The average BMI was 34.7 kg/m2 (range 18.1-55.5). Seventy-six percent had an initial BMI above the 95th percentile. Interactions with providers at the initial visit included a pediatric endocrinologist (100%), health psychologist (60.9%), dietitian (75.5%) and gynecologist (70.9%). Seventy one percent returned for a follow-up visit, (average time of 4.5 months between visits) with 57% achieving weight loss (average 3.5 kg) and an additional 12.6% demonstrating no significant weight gain (< 1.5 kg). Thus, 69.6% demonstrated weight loss/stabilization. ConclusionsIn this multidisciplinary clinic for adolescents with PCOS, nearly 70% of patients succeeded in short-term weight stabilization, with 57% demonstrating weight loss. Interactions with the health psychologist and dietitian appeared to play a key role in successful weight control, supporting the importance of psychology and nutrition expertise in the management of this disorder.

Highly Successful Weight Control by Formerly Obese Adolescents: A Qualitative Test of the Healthy Obsession Model

The Healthy Obsession Model (HOM) suggests that successful weight controllers must develop a preoccupation with the planning and execution of target behaviors to reach and maintain healthy weights (e.g., controlled eating, consistent selfmonitoring). This model further posits that committed weight controllers will feel substantial anxiety or frustration when lapses occur, which, in turn, will motivate them to reinstate target behaviors. The present study tested the HOM by examining the perceptions and attitudes of four very successful and four relatively unsuccessful adolescent weight controllers 1 year after completing immersion treatment. We expected that successful weight controllers, more so than unsuccessful weight controllers, would report more elaborate definitions of their healthy obsessions and describe more negative reactions to potential and actual lapses. In-depth interviews were conducted using a version of the Scanlan Collaborative Interview Method. Reliable coding of the interviews produced results that supported the hypothesis that highly successful weight controllers seem to nurture strong healthy obsessions, including clear definitions of healthy obsessions, heightened commitment based on the emotional impact of excess weight, and negative reactions to lapses. In addition, these adolescent weight controllers seemed motivated by some of the same factors that elite athletes identified in the Sport Commitment Model (e.g., Emotional and Experiential Consequences; Social Support of Parents, Friends, and Peers; Institutional Influences; and Valuable Opportunities).

Highly Successful Weight Control by Formerly Obese Adolescents: A Qualitative Test of the Healthy Obsession Model

Highly Successful Weight Control by Formerly Obese Adolescents: A Qualitative Test of the Healthy Obsession Model

Change in eating behaviors in a 6 month pilot worksite weight loss intervention

The eating behavior constructs restraint, hunger and disinhibition may play an important role in successful weight control. However, the extent to which these constructs can be influenced to sustain weight loss during an intervention remains uncertain. The objective of this pilot study was to determine whether a weight loss intervention at worksites would cause significant changes in eating behaviors. A 6‐mo randomized controlled trial was conducted at 4 worksites [2 intervention (I), 2 control(C)] in the Boston metropolitan area. Measures included fasting body weight and eating behavior assessed using the Eating Inventory at baseline and 6‐months. Results were analyzed using an ANCOVA model with baseline scores as covariates. There were significant increases in restraint (I=5.43±4.25, C=0.29±3.80,p&lt;0.001), decreases in disinhibition (I=−2.5±3.63, C=0.66±1.85, p&lt;0.001) and hunger scores (I=−2.79±3.13, C=0.56±2.63, p&lt;0.001) in the I compared to the C group. Within the I group, decrease in hunger is the strongest predictor of weight loss, the model contributing to 32% of the variance (p&lt;0.001) after controlling for gender and site. This is in contrast to previous studies that have shown change in restraint to be the strongest predictor of weight loss. These findings identify reduction in hunger as an important predictor of successful weight loss.Grant Funding Source: HNRCA

Preadolescents’ and Parents’ Dietary Coping Efficacy During Behavioral Family-Based Weight Control Treatment

Developmentally relevant high-risk dietary situations (e.g., parties where tempting foods are available) may influence overweight youth's weight control, as they increase risk for overeating. Better self-efficacy for coping with these situations-which preadolescents may learn from their parents-could foster successful weight control. Overweight preadolescents (N=204) ages 7-12years (67% female), each with one parent, separately completed the Hypothetical High-Risk Situation Inventory (HHRSI) pre- and post-weight loss treatment. The HHRSI assesses temptation to overeat and confidence in refraining from overeating in response to four high-risk dietary scenarios. Participants generated coping strategies for each scenario. Coping strategies and confidence increased and temptation decreased from pre- to post-weight loss treatment. Parents' increase in confidence from pre- to post-treatment was associated with preadolescents' and parents' weight loss. Tailoring treatments to enhance parents' coping skills (e.g., building strategies, targeting high temptation/low confidence scenarios) may maximize preadolescents' weight control.

Reducing Excessive Gestational Weight Gain: Lessons from the Weight Control Literature and Avenues for Future Research

Excessive gestational weight gain is a prevalent problem and an independent predictor of future obesity in both mothers and offspring. Intervention research to prevent excessive gestational weight gain is still in its infancy but results to date have been quite modest. Research in weight control outside of pregnancy over the past 30 years has been more robust and identified several key components of effective programs, including use of caloric restriction, daily diet self-monitoring, self-weighing, behavior therapy and ongoing patient-provider contact. The aim of this article is to summarize intervention components shown to be effective in promoting successful weight control outside of pregnancy and explore potential applications in pregnancy. Available evidence suggests that the strategies shown to be effective for weight control outside of pregnancy may also promote better weight control in pregnancy, but several lines for future investigation remain.

Lorcaserin and the Role of 5-HT2C Agonism in the Treatment of Obesity

The serotonin (5-HT) system is implicated in the control of human appetite expression. However, previous serotonergic approaches to obesity, d-fenfluramine and sibutramine, were withdrawn over issues of safety. Selectively targeting hypothalamic 5-HT2C receptors should reduce the side effects produced by previous treatment. Lorcaserin is the first of a new generation of highly selective 5-HT2C agonists to pass through clinical development. Data is limited but the drug produces significant reductions in energy intake. These appear small compared to those reportedly produced by sibutramine and there is little evidence to indicate behavioural specificity or a clear satiety effect. However, Lorcaserin produces significant placebo-subtracted weight loss over two years of treatment which may be greater than current treatments such as the lipase inhibitor orlistat. Drugs that strengthen satiety may help individuals resist the urge to over-consume and maintain the reduction in energy intake required for successful weight control. However, for a number of patients Lorcaserin proved to be ineffective. For a centrally acting agent the drug's effect on appetite and behaviour remain poorly characterised. In summary, Lorcaserin produces statistically significant effects on energy intake, but the clinical significance of these findings is still debatable. Furthermore, the history of serotonin drugs indicates caution is warranted.

Exercise Autonomous Motivation Predicts 3-yr Weight Loss in Women

This study evaluated exercise-related predictors of successful long-term weight control in women by analyzing the extent to which sustained exercise participation and self-determination theory (SDT)-based exercise motivation variables mediated the impact of a behavioral weight control intervention on 3-yr weight change. Longitudinal randomized controlled trial consisting of a 1-yr SDT-based intervention and a 2-yr follow-up with 221 female participants (means ± SD: age = 37.6 ± 7 yr, body mass index = 31.6 ± 4.1 kg·m(-2)). The tested model incorporated experimentally manipulated perceived need support, motivational regulations, and 2-yr exercise adherence as mediators of the intervention's impact on 3-yr weight change. Paths were tested using partial least squares analysis. Where there were significant intervening paths, tests of mediation were conducted. Treatment had significant effects on 1- and 2-yr autonomous regulations, 2-yr physical activity, and 3-yr weight change, fully mediated by the tested paths (effect ratio = 0.10-0.61). Moderate and vigorous exercise at 2 yr had a significant effect (P < 0.001) on weight loss success at 3 yr and partially mediated the effect of treatment on weight change. The 2-yr autonomous regulation effects on follow-up weight change were only partially mediated by physical activity (effect ratio = 0.42). This application of SDT to physical activity and weight management showed that not all types of motivation predict long-term behavioral outcomes and that sustained moderate and vigorous exercise mediated long-term weight change. It provides strong evidence for a link between experimentally increased autonomous motivation and exercise and long-term weight loss maintenance. Results highlight the importance of interventions targeting the internalization of exercise behavioral regulation and making exercise and physical activity positive and meaningful experiences rather than simply focusing on immediate behavior change in overweight/obese women.

Weight-Loss Camps in the U.S. and the Immersion-to-Lifestyle Change Model

Childhood ObesityVol. 6, No. 6 Weight-Loss Camps in the U.S. and the Immersion-to-Lifestyle Change ModelDaniel S. KirschenbaumDaniel S. KirschenbaumSearch for more papers by this authorPublished Online:28 Dec 2010https://doi.org/10.1089/chi.2010.0604.persAboutSectionsPDF/EPUB ToolsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail FiguresReferencesRelatedDetailsCited byTargeting Pediatric Obesity via a Healthy Lifestyle Summer Camp Intervention: How Necessary Is a Parenting Component? Jennifer Coto and Paulo A. Graziano27 June 2022 | Childhood Obesity, Vol. 18, No. 5Summer Healthy-Lifestyle Intervention Program for Young Children Who Are Overweight: Results from a Nonrandomized Pilot TrialJournal of Developmental & Behavioral Pediatrics, Vol. 38, No. 9Participation as a leader in immersion weight loss treatment: a 1-year follow-up study7 December 2015 | Clinical Obesity, Vol. 6, No. 1Participation as a leader in immersion weight loss treatment may benefit, not harm, young adult staff members30 June 2015 | Clinical Obesity, Vol. 5, No. 4Evaluation of BMI in obese adolescents at weight-loss camp with the Boy Scouts of America1 January 2015 | Paediatrics and Health, Vol. 3, No. 1“I See Inspiration Everywhere”: Potential Keys to Nurturing Healthy Obsessions by Very Successful Young Weight Controllers Kristen J. Caraher and Daniel S. Kirschenbaum11 December 2014 | Childhood Obesity, Vol. 10, No. 6Current Approaches to the Management of Pediatric Overweight and Obesity11 September 2014 | Current Treatment Options in Cardiovascular Medicine, Vol. 16, No. 11Convergent Validity of the Clinical Assessment of Depression as a Screening Procedure in Immersion Treatment of Adolescent Obesity20 November 2014 | Child & Family Behavior Therapy, Vol. 36, No. 4Dietary self-monitoring and long-term success with weight management13 June 2014 | Obesity, Vol. 22, No. 9“Let's Move” Campaign: Applying the Extended Parallel Process Model28 July 2014 | Social Work in Public Health, Vol. 29, No. 5Camp-Based Immersion Treatment for Obese, Low Socioeconomic Status, Multi-Ethnic Adolescents Marissa E. Carraway, Lesley D. Lutes, Yancey Crawford, Keeley J. Pratt, Amy Gross McMillan, Lee G. Scripture, Sarah Henes, James Cox, Paul Vos, and David N. Collier9 April 2014 | Childhood Obesity, Vol. 10, No. 2Five Recent Expert Recommendations on the Treatment of Childhood and Adolescent Obesity: Toward an Emerging Consensus—A Stepped Care Approach Daniel S. Kirschenbaum and Kristen J. Gierut4 October 2013 | Childhood Obesity, Vol. 9, No. 5Integrating metabolomic signatures and psychosocial parameters in responsivity to an immersion treatment model for adolescent obesity29 February 2012 | Metabolomics, Vol. 8, No. 6Highly Successful Weight Control by Formerly Obese Adolescents: A Qualitative Test of the Healthy Obsession Model Kristen J. Gierut, Kristina M. Pecora, and Daniel S. Kirschenbaum12 October 2012 | Childhood Obesity, Vol. 8, No. 5Healthy Lifestyle Camp: Take Off 4-Health David N. Collier, Yancey Crawford, and Kathryn M. Kolasa5 May 2011 | Childhood Obesity, Vol. 7, No. 2A Welcome Example of Another Immersion-CBT Weight Loss Camp: Response to Collier, Crawford, and Kolasa's Letter to the Editor Daniel S. Kirschenbaum5 May 2011 | Childhood Obesity, Vol. 7, No. 2 Volume 6Issue 6Dec 2010 Information©2010 by Mary Ann Liebert, Inc.To cite this article:Daniel S. Kirschenbaum.Weight-Loss Camps in the U.S. and the Immersion-to-Lifestyle Change Model.Childhood Obesity.Dec 2010.318-323.http://doi.org/10.1089/chi.2010.0604.persPublished in Volume: 6 Issue 6: December 28, 2010PDF download

Using positive deviance for determining successful weight-control practices.

Based on positive deviance (examining the practices of successful individuals), we identified five primary themes from 36 strategies that help to maintain long-term weight loss (weight control) in 61 people. We conducted in-depth interviews to determine what successful individuals did and/or thought about regularly to control their weight. The themes included weight-control practices related to (a) nutrition: increase water, fruit, and vegetable intake, and consistent meal timing and content; (b) physical activity: follow and track an exercise routine at least 3x/week; (c) restraint: practice restraint by limiting and/or avoiding unhealthy foods; (d) self-monitor: plan meals, and track calories/weight progress; and (e) motivation: participate in motivational programs and cognitive processes that affect weight-control behavior. Using the extensive data involving both the practices and practice implementation, we used positive deviance to create a comprehensive list of practices to develop interventions for individuals to control their weight.

Mediators of Weight Loss and Weight Loss Maintenance in Middle‐aged Women

Long-term behavioral self-regulation is the hallmark of successful weight control. We tested mediators of weight loss and weight loss maintenance in middle-aged women who participated in a randomized controlled 12-month weight management intervention. Overweight and obese women (N = 225, BMI = 31.3 +/- 4.1 kg/m(2)) were randomly assigned to a control or a 1-year group intervention designed to promote autonomous self-regulation of body weight. Key exercise, eating behavior, and body image variables were assessed before and after the program, and tested as mediators of weight loss (12 months, 86% retention) and weight loss maintenance (24 months, 81% retention). Multiple mediation was employed and an intention-to-treat analysis conducted. Treatment effects were observed for all putative mediators (Effect size: 0.32-0.79, P < 0.01 vs. controls). Weight change was -7.3 +/- 5.9% (12-month) and -5.5 +/- 5.0% (24-month) in the intervention group and -1.7 +/- 5.0% and -2.2 +/- 7.5% in controls. Change in most psychosocial variables was associated with 12-month weight change, but only flexible cognitive restraint (P < 0.01), disinhibition (P < 0.05), exercise self-efficacy (P < 0.001), exercise intrinsic motivation (P < 0.01), and body dissatisfaction (P < 0.05) predicted 24-month weight change. Lower emotional eating, increased flexible cognitive restraint, and fewer exercise barriers mediated 12-month weight loss (R(2) = 0.31, P < 0.001; effect ratio: 0.37), but only flexible restraint and exercise self-efficacy mediated 24-month weight loss (R(2) = 0.17, P < 0.001; effect ratio: 0.89). This is the first study to evaluate self-regulation mediators of weight loss and 2-year weight loss maintenance, in a large sample of overweight women. Results show that lowering emotional eating and adopting a flexible dietary restraint pattern are critical for sustained weight loss. For long-term success, interventions must also be effective in promoting exercise intrinsic motivation and self-efficacy.

Nutrition and exercise prevent excess weight gain in overweight pregnant women.

To determine the effect of a Nutrition and Exercise Lifestyle Intervention Program (NELIP) for overweight (OW) and obese (OB) pregnant women on pregnancy weight gain, birth weight, and maternal weight retention at 2 months postpartum. This is a single-arm intervention matched by prepregnant body mass index, age, and parity to a historical cohort (4:1). Women with a prepregnancy body mass index of > or = 25.0 kg x m(-2) (N = 65) participated in a NELIP starting at 16-20 wk of pregnancy, continuing until delivery. NELIP consisted of an individualized nutrition plan with total energy intake of approximately 2000 kcal x d(-1) (8360 kJ x d(-1)) and 40%-55% of total energy intake from carbohydrate. Exercise consisted of a walking program (30% HR reserve), three to four times per week, using a pedometer to count steps. Matched historical cohort (MC; N = 260) was from a large local perinatal database. Weight gained by women on the NELIP was 6.8 +/- 4.1 kg (0.38 +/- 0.2 kg x wk(-1)), with a total pregnancy weight gain of 12.0 +/- 5.7 kg. Excessive weight gain occurred before NELIP began at 16 wk of gestation. Eighty percent of the women did not exceed recommended pregnancy weight gain on NELIP. Weight retention at 2 months postpartum was 2.2 +/- 5.6 kg with no difference between the OW and the OB women on NELIP. Mean birth weight was not different between NELIP (3.59 +/- 0.5 kg) and MC (3.56 +/- 0.6 kg, P > 0.05). NELIP reduces the risk of excessive pregnancy weight gain with minimal weight retention at 2 months postpartum in OW and OB women. This intervention may assist OW and OB women in successful weight control after childbirth.