Psychometric validation of four-item exercise identity and healthy-eater identity scales and applications in weight loss maintenance.

BACKGROUND: Identifying as someone who engages in health promoting behaviors like healthy eating and exercising may be associated with sustained engagement in those behaviors, but reliable and valid instruments are needed to improve the rigor of this research. Two studies were conducted to (1) examine the psychometric properties of a four-item exerciser identity measure (4-EI) and an adapted healthy-eater identity measure (4-HEI) and (2) examine differences in identity strengths across categories of weight loss success. METHODS: Data from 1,709 community dwelling adults in the International Weight Control Registry (IWCR) were used. A random half of the sample was used to assess the proposed unidimensional factor structure of the 4-EI and 4-HEI and examine convergent and discriminant validity using Spearman rank-order correlations. One-way ANOVA was used in the other random half of the sample to compare 4-EI and 4-HEI scores (-3 to + 3) across three self-defined weight loss categories ('Successful', 'Regain', and 'Unsuccessful') and those maintaining ≥ 5% weight loss for > 1 year vs. not. RESULTS: Results support the unidimensional factor structure with all four items (eigenvalue scores > 2.89) as well as convergent and discriminant validity for both measures. Exercise identity was strongly correlated with self-reported physical activity (r (735) = 0.52, p <.001) and measures of autonomous motivation. Healthy eating identity was moderately correlated with cognitive restraint in eating (r (744) = 0.42, p <.001) and other measures predictive of eating behavior. 4-EI and 4-HEI are stronger in Successful (4-EI: M = 0.90, SD = 1.77; 4-HEI: M = 1.56 SD = 1.37) vs. Regain (4-EI: M=-0.18, SD = 1.68; 4-HEI: M =.57, SD = 1.48) and Unsuccessful (4-EI:M=-0.28, SD = 1.62; 4-HEI: M = 0.51, SD = 1.33) and those maintaining ≥ 5% weight loss (4-EI:M = 0.47, SD = 1.78; 4-HEI: M = 1.13, SD = 1.49) vs. not (4-EI:M=-0.27, SD = 1.66; 4-HEI: M = 0.53, SD = 1.47), p's < 0.001. CONCLUSIONS: The 4-EI and 4-HEI have acceptable psychometric properties and can advance understanding of the role of identity in exercise and dietary behaviors and weight loss maintenance. TRIAL REGISTRATION: The parent observational study, International Weight Control Registry (IWCR), for these sub-studies is registered in ClinicalTrials.gov (NCT04907396).

Physical activity, inactivity and sleep during the Diabetes Remission Clinical Trial (DiRECT).

AIMS: As sustained weight loss is vital for achieving remission of type 2 diabetes, we explored whether randomisation to weight loss plus maintenance in the DiRECT trial was associated with physical activity, inactivity or sleep. METHODS: Participants were randomised to either a dietary weight management programme or best-practice care. The weight management group were encouraged to increase daily physical activity to their sustainable maximum. Objective measurement was achieved using a wrist-worn GENEActiv accelerometer for 7 days at baseline, 12 and 24 months in both groups. RESULTS: Despite average weight loss of 10 kg at 12 months in the intervention (n = 66) group, there were no differences in total physical activity or inactivity compared with the control (n = 104) at any time point. However, in our exploratory analysis, those who lost more than 10% of their baseline body weight performed on average 11 mins/day more light activity than the <10% group at 24 months (p = 0.033) and had significantly lower bouts of Inactivity30min (interaction, p = 0.005) across 12 and 24 months. At 24 months, the ≥10% group had higher daily acceleration (38.5 ± 12.1 vs. 33.2 ± 11.1 mg, p = 0.020), and higher accelerations in the most active 5-hour period (59.4 ± 21.8 vs. 50.6 ± 18.3 mg, p = 0.023). Wakefulness after sleep onset decreased in the intervention group compared with the control group and also in the ≥10% weight loss group at 12 and 24 months. CONCLUSIONS: Randomisation to a successful intensive weight loss intervention, including regular physical activity encouragement, was not associated with increased physical activity although sleep parameters improved. Physical activity was greater, and night-time waking reduced in those who maintained >10% weight loss at 12 and 24 months. TRIAL REGISTRATION ISRCTN03267836.

The Role of Physical Activity in Long-term Weight Loss: 36-month Results From a Randomized Controlled Trial.

BACKGROUND: Physical activity (PA) may promote long-term weight loss, but facilitating high levels of PA in behavioral weight loss programs is challenging. PURPOSE: This study reports the 36-month follow-up of a behavioral weight loss trial that tested the efficacy of increasing the emphasis on PA during treatment and using traditional or acceptance-based therapy (ABT) for this purpose. We also examined the extent to which long-term weight loss differed by PA pattern and tested if individual differences in eating behavior moderated this relationship. METHODS: Participants (N = 320) were randomized to (1) standard behavioral weight loss treatment (BT), (2) BT with a focus on PA, or (3) ABT with a focus on PA. Weight loss and PA were measured at 24- and 36-month follow-up. RESULTS: There were no differences between conditions in weight loss or PA at 24 or 36 months. Participants consistently engaging in high PA experienced the greatest weight losses. The positive impact of PA on weight loss was more pronounced among those with low emotional eating and those who believed that exercise did not affect their appetite. CONCLUSIONS: Findings emphasize the difficulty of improving long-term PA among adults with overweight/obesity beyond what standard behavioral weight loss treatment achieves. This study highlights the need to develop new PA treatment strategies, and suggests that ABT for weight loss may be more effective when applied to eating behavior versus PA. Results also demonstrate the importance of addressing problematic eating behavior and cognitions to fully realize the benefits of PA for weight loss. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov identifier: NCT02363010.

Social Environmental Predictors of Lapse in Dietary Behavior: An Ecological Momentary Assessment Study Amongst Dutch Adults Trying to Lose Weight.

BACKGROUND: When losing weight, most individuals find it difficult to maintain a healthy diet. Social environmental conditions are of pivotal importance in determining dietary behavior. To prevent individuals from lapsing, insight in social environmental predictors of lapse in dietary behavior is needed. PURPOSE: Identify social environmental predictors of lapse in dietary behavior, using ecological momentary assessment (EMA) amongst Dutch adults trying to lose weight. METHODS: Adults (N = 81) participated in two 7-day EMA weeks. Six times a day semi-random prompts were sent. At each prompt, participants indicated whether a lapse had occurred and responded to questions assessing social support, descriptive norm, injunctive norm, social pressure, presence of others, and current location. Generalized estimating equations were used to examine associations with lapse. RESULTS: Injunctive norm (OR = 1.07, 95% CI = 1.03-1.11), descriptive norm (OR = 1.04, 95% CI = 1.02-1.07), and social pressure (OR = 1.09, 95% CI = 1.05-1.14), all toward diverting from diet plans, predicted lapses. Social support toward sticking to diet plans and presence of others did not predict lapses. When controlling for a prior lapse, all other associations became nonsignificant. Lapses occurred most often at home and gradually occurred more often during the day. CONCLUSIONS: Traditional public health perspectives have mainly focused on individual choice and responsibility for overweight related unhealthy lifestyles. This study shows that there may be opportunities to enhance intervention programs by also focusing on social norms and social pressure. The involvement of partners or housemates may create more awareness of the impact of (unintentional) social pressure on risk of lapsing, and reduce the level of exerted social pressure.

When losing weight, most individuals find it difficult to maintain a healthy diet. As social environmental conditions are of pivotal importance in determining dietary behavior, insight in social environmental predictors of lapse in dietary behavior is needed to prevent individuals from lapsing. Therefore, this study identified social environmental predictors of lapse in dietary behavior, using ecological momentary assessment (EMA) amongst Dutch adults trying to lose weight. A total of 81 participants took part in two 7-day EMA weeks, in which six times a day semi-random prompts were sent. At each prompt, participants indicated whether a lapse had occurred and responded to questions assessing social support, descriptive norm, injunctive norm, social pressure, presence of others, and current location. The results show that injunctive norm, descriptive norm, and social pressure, all toward diverting from diet plans, predicted dietary lapses. Social support toward sticking to diet plans and presence of others did not predict dietary lapses. Additionally, lapses occurred most often at home and gradually occurred more often during the day. This study shows that there may be opportunities to enhance intervention programs by also focusing on social norms and social pressure.

Do monthly coaching calls influence proximal participant adherence in a behavioral weight loss program?

Participants who receive continued coach contact following behavioral weight loss treatment are more successful in maintaining their weight loss long-term. The current study examines whether these contacts have dynamic effects, such that participants are most adherent to the prescribed weight loss behaviors in the days after the call, when motivation and goal salience may be heightened, than they are as time goes on. The current study examined the trajectory of calorie intake, physical activity, weight, and self-monitoring behavior in the fourteen days after a monthly coaching call among participants completing the maintenance phase of a behavioral weight loss trial. For physical activity outcomes, caloric intake, and weight, there were no changes across time. Participants did have the highest adherence and quality of dietary self-monitoring immediately after the call, which diminished over time. Coach contact may continually renew commitment to this burdensome but critical behavior. Likelihood of self-weighing showed an opposite trend, where participants were more likely to weigh themselves in the days more distal from the coach call. Results can inform the timing and content of future coach contact to promote weight control.

Age- and sex-specific effects of a long-term lifestyle intervention on body weight and cardiometabolic health markers in adults with prediabetes: results from the diabetes prevention study PREVIEW.

AIMS/HYPOTHESIS: Lifestyle interventions are the first-line treatment option for body weight and cardiometabolic health management. However, whether age groups or women and men respond differently to lifestyle interventions is under debate. We aimed to examine age- and sex-specific effects of a low-energy diet (LED) followed by a long-term lifestyle intervention on body weight, body composition and cardiometabolic health markers in adults with prediabetes (i.e. impaired fasting glucose and/or impaired glucose tolerance). METHODS: This observational study used longitudinal data from 2223 overweight participants with prediabetes in the multicentre diabetes prevention study PREVIEW. The participants underwent a LED-induced rapid weight loss (WL) period followed by a 3 year lifestyle-based weight maintenance (WM) intervention. Changes in outcomes of interest in prespecified age (younger: 25-45 years; middle-aged: 46-54 years; older: 55-70 years) or sex (women and men) groups were compared. RESULTS: In total, 783 younger, 319 middle-aged and 1121 older adults and 1503 women and 720 men were included in the analysis. In the available case and complete case analyses, multivariable-adjusted linear mixed models showed that younger and older adults had similar weight loss after the LED, whereas older adults had greater sustained weight loss after the WM intervention (adjusted difference for older vs younger adults -1.25% [95% CI -1.92, -0.58], p<0.001). After the WM intervention, older adults lost more fat-free mass and bone mass and had smaller improvements in 2 h plasma glucose (adjusted difference for older vs younger adults 0.65 mmol/l [95% CI 0.50, 0.80], p<0.001) and systolic blood pressure (adjusted difference for older vs younger adults 2.57 mmHg [95% CI 1.37, 3.77], p<0.001) than younger adults. Older adults had smaller decreases in fasting and 2 h glucose, HbA1c and systolic blood pressure after the WM intervention than middle-aged adults. In the complete case analysis, the above-mentioned differences between middle-aged and older adults disappeared, but the direction of the effect size did not change. After the WL period, compared with men, women had less weight loss (adjusted difference for women vs men 1.78% [95% CI 1.12, 2.43], p<0.001) with greater fat-free mass and bone mass loss and smaller improvements in HbA1c, LDL-cholesterol and diastolic blood pressure. After the WM intervention, women had greater fat-free mass and bone mass loss and smaller improvements in HbA1c and LDL-cholesterol, while they had greater improvements in fasting glucose, triacylglycerol (adjusted difference for women vs men -0.08 mmol/l [-0.11, -0.04], p<0.001) and HDL-cholesterol. CONCLUSIONS/INTERPRETATION: Older adults benefited less from a lifestyle intervention in relation to body composition and cardiometabolic health markers than younger adults, despite greater sustained weight loss. Women benefited less from a LED followed by a lifestyle intervention in relation to body weight and body composition than men. Future interventions targeting older adults or women should take prevention of fat-free mass and bone mass loss into consideration. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT01777893.

Participant experiences in the Diabetes REmission Clinical Trial (DiRECT).

INTRODUCTION: The Diabetes REmission Clinical Trial (DiRECT) has shown that sustained remission of type 2 diabetes in primary care is achievable through weight loss using total diet replacement (TDR) with continued behavioural support. Understanding participants' experiences can help optimise the intervention, support implementation into healthcare, and understand the process of behaviour change. METHODS: Thirty-four DiRECT participants were recruited into this embedded qualitative evaluation study. In-person and telephone interviews were conducted before the TDR; at week 6-8 of the TDR; 2 weeks into food reintroduction (FR); and at 1 year, to learn about participant experiences with the programme. Transcribed narratives were analysed thematically, and we used interpretation to develop overarching themes. RESULTS: Initiation of the TDR and transition to FR were challenging and required increased behavioural support. In general, adhering to TDR proved easier than the participants had anticipated. Some participants chose the optional extension of TDR. Rapid weight loss and changes in diabetes markers provided ongoing motivation. Further weight loss, behavioural support and occasional use of TDR facilitated weight loss maintenance (WLM). A process of behaviour adaptation to change following regime disruption was identified in three stages: (1) expectations of the new, (2) overcoming difficulties with adherence, and (3) acceptance of continuous effort and establishment of routines. CONCLUSIONS: The DiRECT intervention was acceptable and regularity, continuity, and tailoring of behavioural support was instrumental in its implementation in primary care. The adaptation process accounts for some of the individual variability of experiences with the intervention and highlights the need for programme flexibility.

Using health economic modelling to inform the design and development of an intervention: estimating the justifiable cost of weight loss maintenance in the UK.

BACKGROUND: There is a need to develop cost-effective weight loss maintenance interventions to prolong the positive impact of weight loss on health outcomes. Conducting pre-trial health economic modelling is recommended to inform the design and development of behavioural interventions. We aimed to use health economic modelling to estimate the maximum cost per-person (justifiable cost) of a cost-effective behavioural weight loss maintenance intervention, given an estimated intervention effect for individuals with: i) a Body Mass Index (BMI) of 28 kg/m2 or above without diabetes and ii) a diagnosis of type 2 diabetes prescribed a single non-insulin diabetes medication. METHODS: The School for Public Health Research Diabetes prevention model was used to estimate the lifetime Quality-adjusted life year (QALY) gains, healthcare costs, and maximum justifiable cost associated with a weight loss maintenance intervention. Based on a meta-analysis, the estimated effect of a weight loss maintenance intervention following a 9 kg weight loss, was a regain of 1.33 kg and 4.38 kg in years one and two respectively compared to greater regain of 2.84 kg and 5.6 kg in the control group. Sensitivity analysis was conducted around the rate of regain, duration of effect and initial weight loss. RESULTS: The justifiable cost for a weight loss maintenance intervention at an ICER of £20,000 per QALY was £104.64 for an individual with a BMI of 28 or over and £88.14 for an individual with type 2 diabetes. Within sensitivity analysis, this varied from £36.42 to £203.77 for the former, and between £29.98 and £173.05 for the latter. CONCLUSIONS: Researchers developing a weight loss maintenance intervention should consider these maximum justifiable cost estimates and the potential impact of the duration of effect and initial weight loss when designing intervention content and deciding target populations. Future research should consider using the methods demonstrated in this study to use health economic modelling to inform the design and budgetary decisions in the development of a behavioural interventions.

What happens after a weight loss intervention? A qualitative study of drivers and challenges of maintaining time-restricted eating among people with overweight at high risk of type 2 diabetes.

Time-restricted eating (TRE)1 has been conceptualised as a strategy for achieving weight loss and improving metabolic health, but limited knowledge exists about how people can maintain TRE in daily life. This study examined how TRE was maintainable in daily life after a three-month intervention (the RESET study) in which participants were encouraged to consume all food and beverages except water within a 10-h daily window. Specifically, we examined TRE maintenance patterns across participants, including drivers and challenges for maintenance success. A qualitative longitudinal study was conducted, and twenty participants with overweight at high risk of type 2 diabetes were interviewed using a semi-structured interview guide at the end of the intervention and after a three-month follow-up period. Data were analysed longitudinally in two steps inspired by a pattern-oriented longitudinal analysis approach. Seven participants maintained a strict 10-h window, ten maintained an adjusted TRE regimen (e.g., taking days off), and three did not attempt maintenance. Maintenance drivers included consistent daily rhythms and regular meal patterns, subjective experiences (e.g., feeling healthier), making flexible adjustments to the TRE regimen, family support and avoiding feelings of guilt. Maintenance challenges included social evening events, inconsistent daily rhythms and eating patterns, preoccupation with losing weight, lack of family support and self-blame. TRE was manageable for most participants; however, personalised support for adjusting TRE to daily life is needed to ensure long-term maintenance. Future studies should explore the effectiveness of a personalised TRE concept to determine the usefulness of TRE in real-life settings.

Factors associated with food choice among long-term weight loss maintainers.

BACKGROUND: The present study aimed to examine motivations for food choice among long-term weight loss maintainers (WLM) in a widely used commercial weight management program. METHODS: A cross-sectional study was employed where determinants of food choice were measured in the USA using validated scales: Food Choice Questionnaire, Consideration of Future Consequences, and Eating in the Absence of Hunger. Participants were 3806 WLM following a commercial weight management program (WW International, Inc.) who had maintained a weight loss ≥ 9.1 kg (mean 24.7 kg) for 3.3 years and had a body mass index (BMI) of 27.6 kg m2 . A control group of weight stable individuals with obesity (controls; n = 519) had a BMI of 38.9 kg m2 and a weight change < 2.3 kg over the previous 5 years. RESULTS: WLM vs. controls made food decisions more based on health (18.9 vs. 16.3; ηp 2 = 0.052) and weight control (9.9 vs. 7.5; ηp 2 = 0.16) and less based on price (8.4 vs. 9.1; ηp 2 = 0.10). WLM also scored higher than controls with respect to considering future consequences of behaviours (44.3 vs. 38.4; ηp 2 = 0.060) and reported less external eating in the absence of hunger (7.1 vs. 7.5; ηp 2 = 0.058). Standard canonical coefficients indicated that making food choices based on weight (0.717) with less value placed on price (-0.33) and greater consideration of future consequences (0.262) contributed independently and most (overall r = 0.593; p = 0.0001) to discriminating WLM from controls. CONCLUSIONS: In a widely used commercial weight management program, successful WLM reported food decisions based more on weight and less on price and considered future consequences of current behaviours.

Users' Experiences With the NoHoW Web-Based Toolkit With Weight and Activity Tracking in Weight Loss Maintenance: Long-term Randomized Controlled Trial.

BACKGROUND: Digital behavior change interventions (DBCIs) offer a promising channel for providing health promotion services. However, user experience largely determines whether they are used, which is a precondition for effectiveness. OBJECTIVE: The primary aim of this study is to evaluate user experiences with the NoHoW Toolkit (TK)-a DBCI that targets weight loss maintenance-over a 12-month period by using a mixed methods approach and to identify the main strengths and weaknesses of the TK and the external factors affecting its adoption. The secondary aim is to objectively describe the measured use of the TK and its association with user experience. METHODS: An 18-month, 2×2 factorial randomized controlled trial was conducted. The trial included 3 intervention arms receiving an 18-week active intervention and a control arm. The user experience of the TK was assessed quantitatively through electronic questionnaires after 1, 3, 6, and 12 months of use. The questionnaires also included open-ended items that were thematically analyzed. Focus group interviews were conducted after 6 months of use and thematically analyzed to gain deeper insight into the user experience. Log files of the TK were used to evaluate the number of visits to the TK, the total duration of time spent in the TK, and information on intervention completion. RESULTS: The usability level of the TK was rated as satisfactory. User acceptance was rated as modest; this declined during the trial in all the arms, as did the objectively measured use of the TK. The most appreciated features were weekly emails, graphs, goal setting, and interactive exercises. The following 4 themes were identified in the qualitative data: engagement with features, decline in use, external factors affecting user experience, and suggestions for improvements. CONCLUSIONS: The long-term user experience of the TK highlighted the need to optimize the technical functioning, appearance, and content of the DBCI before and during the trial, similar to how a commercial app would be optimized. In a trial setting, the users should be made aware of how to use the intervention and what its requirements are, especially when there is more intensive intervention content. TRIAL REGISTRATION: ISRCTN Registry ISRCTN88405328; https://www.isrctn.com/ISRCTN88405328. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1136/bmjopen-2019-029425.

Evaluation of the Immediate Effects of Web-Based Intervention Modules for Goals, Planning, and Coping Planning on Physical Activity: Secondary Analysis of a Randomized Controlled Trial on Weight Loss Maintenance.

BACKGROUND: The use of digital interventions can be accurately monitored via log files. However, monitoring engagement with intervention goals or enactment of the actual behaviors targeted by the intervention is more difficult and is usually evaluated based on pre-post measurements in a controlled trial. OBJECTIVE: The objective of this paper is to evaluate if engaging with 2 digital intervention modules focusing on (1) physical activity goals and action plans and (2) coping with barriers has immediate effects on the actual physical activity behavior. METHODS: The NoHoW Toolkit (TK), a digital intervention developed to support long-term weight loss maintenance, was evaluated in a 2 x 2 factorial randomized controlled trial. The TK contained various modules based on behavioral self-regulation and motivation theories, as well as contextual emotion regulation approaches, and involved continuous tracking of weight and physical activity through connected commercial devices (Fitbit Aria and Charge 2). Of the 4 trial arms, 2 had access to 2 modules directly targeting physical activity: a module for goal setting and action planning (Goal) and a module for identifying barriers and coping planning (Barriers). Module visits and completion were determined based on TK log files and time spent in the module web page. Seven physical activity metrics (steps; activity; energy expenditure; fairly active, very active and total active minutes; and distance) were compared before and after visiting and completing the modules to examine whether the modules had immediate or sustained effects on physical activity. Immediate effect was determined based on 7-day windows before and after the visit, and sustained effects were evaluated for 1 to 8 weeks after module completion. RESULTS: Out of the 811 participants, 498 (61.4%) visited the Goal module and 406 (50.1%) visited the Barriers module. The Barriers module had an immediate effect on very active and total active minutes (very active minutes: before median 24.2, IQR 10.4-43.0 vs after median 24.9, IQR 10.0-46.3; P=.047; total active minutes: before median 45.1, IQR 22.9-74.9 vs after median 46.9, IQR 22.4-78.4; P=.03). The differences were larger when only completed Barriers modules were considered. The Barriers module completion was also associated with sustained effects in fairly active and total active minutes for most of the 8 weeks following module completion and for 3 weeks in very active minutes. CONCLUSIONS: The Barriers module had small, significant, immediate, and sustained effects on active minutes measured by a wrist-worn activity tracker. Future interventions should pay attention to assessing barriers and planning coping mechanisms to overcome them. TRIAL REGISTRATION: ISRCTN Registry ISRCTN88405328; https://www.isrctn.com/ISRCTN88405328.

The challenge of weight loss maintenance in obesity: a review of the evidence on the best strategies available.

Long-term weight loss maintenance represents a big challenge for the management of obesity. This narrative review aims to provide an overview of the main endocrine mechanisms involved in weight regain in subjects with obesity and to review the current evidence on the best lifestyle approaches, including diet and physical activity. Weight regain after weight loss occurs in about 50% of subjects with obesity in the absence of lifestyle changes. The primary endocrine mechanism responsible for weight regain involves the brain-gut axis, which encourages food intake and thus weight regain through the secretion and action of several gastrointestinal hormones, such as ghrelin, leptin and cholecystokinin. Several evidence reported changes of secretion of these hormones during weight loss and weight loss maintenance programs. Endurance training is the most effective physical activity to lose and keep weight loss; the association of endurance with resistance training is recommended for remodelling body shape.

The association between binge eating disorder and weight management in overweight and obese adults: A systematic literature review.

Aim: Weight loss is shown to improve obesity-related health problems as long as it is maintained for a long term. The purpose of this systematic review was to investigate the association between binge eating disorder and weight management in overweight and obese adults. Methods: A systematic search following the preferred reporting items for systematic reviews and meta-analyses guidelines was conducted across PubMed, Ebsco and Cochrane Library from inception through December 2020 to identify studies that assessed the association between binge eating disorder and weight management (e.g., weight loss, weight gain and weight loss maintenance) in overweight and obese adults. We included studies that examined adults (≥18 years old) being overweight and obese with and without binge eating behaviour. Two authors independently screened and evaluated studies for methodological quality. Results: Nine articles were selected, including 3685 participants. Three of the included studies were randomised control trials and the remaining were observational studies. The majority of the studies included support that people who have binge eating disorder may have an additional barrier maintaining their weight loss compared to people who do not suffer from binge eating disorder. Conclusion: Our systematic review revealed that binge eating disorder may have a negative association with weight loss maintenance. Further well-conducted prospective cohort studies and randomised clinical trials are required to investigate the possible mechanisms and whether any such mechanisms are modifiable. These will lead us to more efficient strategies targeting weight management.

Diets Varying in Carbohydrate Content Differentially Alter Brain Activity in Homeostatic and Reward Regions in Adults.

BACKGROUND: Obesity has one of the highest refractory rates of all chronic diseases, in part because weight loss induced by calorie restriction, the first-line treatment for obesity, elicits biological adaptations that promote weight regain. Although acute feeding trials suggest a role for macronutrient composition in modifying brain activity related to hunger and satiety, relevance of these findings to weight-loss maintenance has not been studied. OBJECTIVES: We investigated effects of weight-loss maintenance diets varying in macronutrient content on regional cerebral blood flow (rCBF) in brain regions involved in hunger and reward. METHODS: In conjunction with a randomized controlled feeding trial, we investigated the effects of weight-loss maintenance diets varying in carbohydrate content [high, 60% of total energy: n = 20; 6 men/14 women; mean age: 32.5 y; mean BMI (in kg/m 2): 27.4; moderate, 40% of total energy: n = 22; 10 men/12 women; mean age: 32.5 y; mean BMI: 29.0; low, 20% of total energy: n = 28; 12 men/16 women; mean age: 33.2 y; mean BMI: 27.7] on rCBF in brain regions involved in hunger and reward preprandial and 4 h postprandial after 14-20 wk on the diets. The primary outcome was rCBF in the nucleus accumbens (NAcc) at 4 h postprandial; the secondary outcome was preprandial rCBF in the hypothalamus. RESULTS: Consistent with a priori hypothesis, at 4 h postprandial, NAcc rCBF was 43% higher in adults assigned to the high- compared with low-carbohydrate diet {P[family-wise error (FWE)-corrected] < 0.05}. Preprandial hypothalamus rCBF was 41% higher on high-carbohydrate diet [P(FWE-corrected) < 0.001]. Exploratory analyses revealed that elevated rCBF on high-carbohydrate diet was not specific to prandial state: preprandial NAcc rCBF [P(FWE-corrected) < 0.001] and 4 h postprandial rCBF in hypothalamus [P(FWE-corrected) < 0.001]. Insulin secretion predicted differential postprandial activation of the NAcc by diet. CONCLUSIONS: We report significant differences in rCBF in adults assigned to diets varying in carbohydrate content for several months, which appear to be partially associated with insulin secretion. These findings suggest that chronic intake of a high-carbohydrate diet may affect brain reward and homeostatic activity in ways that could impede weight-loss maintenance. This trial was registered at clinicaltrials.gov as NCT02300857.

Prolonged unsupervised Nordic walking and walking exercise following six months of supervision in adults with overweight and obesity: A randomised clinical trial.

BACKGROUND AND AIMS: This study is a randomized trial that examined the effects of 6 months of unsupervised Nordic walking (NW) and walking (W) exercise following 6 months of supervised training in overweight/obese adults. METHODS AND RESULTS: After a 6-month program of diet and supervised training participants (n = 27) of NW (66 ± 7 yrs, body mass index (BMI) 34 ± 5) and W (66 ± 8 yrs, BMI 32 ± 5) group continue the training without supervision for other 6 months. Steps count and mean heart rate (HRmean) were performed in each session; anthropometric and body composition, aerobic capacity and strength of the upper and lower limbs were evaluated at baseline, after 6 months of supervised and 6 months of unsupervised training. In the unsupervised training, monthly sessions and steps count decreased over time in both groups (p < 0.05), with no significant changes in HRmean. Compared to the supervised phase, adherence decreased significantly only in the W group in the last 3 months of unsupervised training. Compared to baseline in both groups BMI did not change, but W group lost total fat; only the NW group maintained (p < 0.05) the gains in arm curl (33%) and chair stand (31%); both groups improved in six-minute walking test (p < 0.05). CONCLUSION: Despite unsupervised training was not effective for a further increase in performance, participants, especially in NW, maintained some of the improvements achieved during the supervision. However, the presence of instructor that guides training, may enhance adherence and health benefits of NW and W exercise. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT03212391 (July 11, 2017).

Weight-related behaviors and weight loss maintenance: a cross-sectional study in Cyprus.

BACKGROUND: This study examined the differences between maintainers and regainers regarding obesity related eating behaviors. A secondary objective was to develop an eating behavior index predicting the likelihood of successful weight loss maintenance. METHODS: The current cross-sectional evaluation conducted in Cyprus was part of the MedWeight (Greek) study. Eligible for participation were Cypriot (maintainers = 145; regainers = 87) adult men and women who reported being at least overweight (BMI ≥25 kg/m2) and experienced an intentional weight loss of ≥10% of their maximum lifetime weight, at least 1 year before participation. Among other assessments, weight-related behaviors were evaluated through Weight-Related Behaviors Index (WRBI). RESULTS: Statistically significant differences between the two groups were observed regarding meals per day (P = 0.008), frequency of eating home cooked meals (P = 0.004) and WRBI total score (P = 0.022). Results from logistic regression models indicated that the odds of maintaining weight loss increase at 30% (Model 1: P < 0.05, Odds ratio 1.306, 1.095-1.556 95% C.I., Model 2: P < 0.05, OR 1.308, 1.097-1.560 95% C.I.) and at 38% after adjusting for physical activity (Model 3: P < 0.05, OR 1.377, 1.114-1.701 95% C.I..) for each point scored in WRBI total score. CONCLUSIONS: Eating more frequently home cooked meals and less eating away from home meals may be beneficially associated with weight loss maintenance. WRBI seems to be a useful tool when dealing with patients who have previously lost significant weight.

Motivations to exercise in young men following a residential weight loss programme conducted in National Service - a mixed methods study.

BACKGROUND: Physical activity is a critical component of lifestyle interventions to reduce body weight and maintain weight loss. The goal of this study was to examine the motivations to exercise in young men following a 5-month residential weight loss programme conducted in the Singapore military as part of National Service. METHODS: We conducted a sequential mixed methods study starting with three focus groups comprising 21 programme instructors. Fifteen former programme participants aged 20.8 years (±1.4) with an average body mass index (BMI) of 29.3 kg/m2 (±4.6) were interviewed in-depth over a total duration of 9 h. Another 487 current programme participants aged 20.8 years (±1.1), BMI 27.1 kg/m2 (±2.6), completed a survey on weight loss, physical fitness, and motivations to exercise using the Behaviours Regulating Exercise Questionnaire (BREQ-3). Qualitative data was coded thematically using the six constructs of exercise motivation described by self-determination theory: amotivation, external, introjected, identified and integrated regulation and intrinsic motivation. Quotes from interviewees were cross-tabulated according to their weight maintenance trajectories. BREQ-3 responses were analysed according to initial body mass index (BMI), percentage weight loss and fitness. RESULTS: Over the course of the residential programme interview and survey participants experienced an average weight loss of 15.6 kg (±6.5) and 13.0 kg (±5.4) respectively. Among the fifteen interviewees seven had gained no more than 34% of initial weight loss 6 months after completing the programme while another eight had gained more than 51%. We elicited three key themes from the data: (1) Barriers to exercise; (2) diminishing extrinsic motivation; and (3) unidentified exercise benefits. The integration of findings uncovered reinforcing motivational patterns in the areas of health, fitness, camaraderie and identified regulation. Narratives of self-acceptance and shift-work environments gave rise to potentially deleterious motivational patterns. Our findings suggest that successful transition from a residential programme to independent weight management requires a more deliberate pivot from predominantly extrinsic to intrinsic motivational approaches. CONCLUSION: Residential programmes such as the one investigated here, should develop a deliberate transition strategy, replace weight loss targets with physical performance goals and promote sports that are appropriate for young men affected by overweight and obesity.

"I didn't want to do it on my own": A qualitative study of women's perceptions of facilitating and risk factors for weight control on a UK commercial community program.

Overweight and obesity remain serious public health concerns. Outcomes from community based commercial weight management programmes vary, relapse is common and drop out is high. Outcomes could be improved by better understanding experiences on these programmes. The aim of our study was to generate accounts of people's experience on a commercial weight-management program to identify what experiences were perceived as facilitating, and what posed risks, to programme effectiveness and compliance. We conducted individual, semi-structured interviews with eighteen Caucasian women (mean age 45.4y) who were members of nation-wide UK commercial, fee-paying, community weight management programme. Interview data was analysed via framework analysis. Participants' experiences indicated that the programme helped by triggering several intra- and interpersonal processes that catalysed change across psychological, physiological, dietary and behavioural areas of their life. Risks to program adherence and effectiveness spanned well-known risks such as self-regulation fatigue and the difficulty of recovering from negative self-criticism, as well as new factors such as the confusing nature of weight change, the relatively powerful impact of everyday events, and the difficulty in getting the balance right between personalised support vs. intrusion. The complexity of reported experiences challenges the linear, predictive pathways of change proposed by many health behaviour models of weight management. To improve effectiveness, programmes need to go well beyond behavioural and dietary support. It is recommended that community, commercial programmes educate people about the physiological and psychological tensions they will encounter, why people lose weight at different rates, the likelihood of weight relapse and strategies to manage these, including evidence-based support for managing self-criticism.

Similar weight loss and maintenance in African American and White women in the Improving Weight Loss (ImWeL) trial.

Objective: African Americans (AA) are often underrepresented and tend to lose less weight than White participants during the intensive phase of behavioral obesity treatment. Some evidence suggests that AA women experience better maintenance of lost weight than White women, however, additional research on the efficacy of extended care programs (i.e. continued contacts to support the maintenance of lost weight) is necessary to better understand these differences.Methods: The influence of race on initial weight loss, the likelihood of achieving ≥5% weight reduction (i.e. extended care eligibility), the maintenance of lost weight and extended care program efficacy was examined in 269 AA and White women (62.1% AA) participating in a 16-month group-based weight management program. Participants achieving ≥5% weight reduction during the intensive phase (16 weekly sessions) were randomized to a clustered campaign extended care program (12 sessions delivered in three, 4-week clusters) or self-directed control.Results: In adjusted models, race was not associated with initial weight loss (p = 0.22) or the likelihood of achieving extended care eligibility (odds ratio 0.64, 95% CI [0.29, 1.38]). AA and White women lost -7.13 ± 0.39 kg and -7.62 ± 0.43 kg, respectively, during initial treatment. There were no significant differences in weight regain between AA and White women (p = 0.64) after adjusting for covariates. Clustered campaign program participants (AA: -6.74 ± 0.99 kg, White: -6.89 ± 1.10 kg) regained less weight than control (AA: -5.15 ± 0.99 kg, White: -4.37 ± 1.04 kg), equating to a 2.12 kg (p = 0.03) between-group difference after covariate adjustments.Conclusions: Weight changes and extended care eligibility were comparable among all participants. The clustered campaign program was efficacious for AA and White women. The high representation and retention of AA participants may have contributed to these findings.