Examining sociodemographic and health-related characteristics as moderators of an mHealth intervention on physical activity outcomes in young adult cancer survivors.

PURPOSE: This study explored whether sociodemographic and health-related characteristics moderated mHealth PA intervention effects on total and moderate-to-vigorous physical activity (MVPA) at 6 months, relative to a self-help condition among young adult cancer survivors (YACS). METHODS: We conducted exploratory secondary analyses of data from a randomized controlled trial among 280 YACS. All participants received digital tools; intervention participants also received lessons, adaptive goals, tailored feedback, text messages, and Facebook prompts. Potential moderators were assessed in baseline questionnaires. PA was measured at baseline and 6 months with accelerometers. Linear model repeated measures analyses examined within- and between-group PA changes stratified by levels of potential moderator variables. RESULTS: Over 6 months, the intervention produced MVPA increases that were ≥ 30 min/week compared with the self-help among participants who were males (28.1 vs. -7.7, p = .0243), identified with racial/ethnic minority groups (35.2 vs. -8.0, p = .0006), had baseline BMI of 25-30 (25.4 vs. -7.2, p = .0034), or stage III/IV cancer diagnosis (26.0 vs. -6.8, p = .0041). Intervention participants who were ages 26-35, college graduates, married/living with a partner, had a solid tumor, or no baseline comorbidities had modest MVPA increases over 6 months compared to the self-help (ps = .0163-.0492). Baseline characteristics did not moderate intervention effects on total PA. CONCLUSIONS: The mHealth intervention was more effective than a self-help group at improving MVPA among subgroups of YACS defined by characteristics (sex, race, BMI, cancer stage) that may be useful for tailoring PA interventions. IMPLICATIONS FOR CANCER SURVIVORS: These potential moderators can guide future optimization of PA interventions for YACS. GOV IDENTIFIER: NCT03569605.

Concordance in dietary intake among caregivers and infants during the period of complementary feeding: A scoping review.

Dietary intake during infancy shapes later food preferences and is important for short- and long-term health and wellbeing. Although caregivers are thought to influence the developing food preferences of infants, children less than two years have been notably absent in existing meta-analyses on the topic. This scoping review seeks to fill this gap by using a systematic process to identify and summarize the published literature on the resemblance of caregiver and infant diet during the period of complementary feeding (6-23 months). Articles were included if they assessed intake of foods or beverages other than human milk or commercial milk formula and reported a test of association between the intake of caregivers and infants. Four electronic databases (PubMed, EMBASE, Scopus, and Global Health) were systematically searched for articles published since 2000. Thirty-three articles, representing 32 studies, were identified. The majority of studies examined infant intake of food groups/items (n = 20), seven studies examined infant dietary patterns, and six studies examined dietary diversity. Studies predominantly reported associations between diets of mothers and infants (n = 31); three studies reported associations for fathers. Most studies assessed infant diet at one timepoint (n = 26), with 12 studies combining the intakes of younger (0-11 months) and older infants (12-23 months). Food groups examined, in order of frequency, included 'non-core' foods and beverages (n = 14), vegetables (n = 13), fruits (n = 12), protein foods (n = 6), grains (n = 5), and dairy foods (n = 4). Definitions of variables for food groups and dietary patterns were highly heterogeneous, but consistent for dietary diversity. Nearly all studies (n = 31) reported significant associations between dietary intakes of caregivers and infants. Findings suggest caregiver diet may be a promising focus for interventions aiming to shape the food preferences and dietary intakes of infants.

"My wellbeing-their wellbeing "- An eHealth intervention for managing obesity in early care and education: Protocol for the Go NAPSACC Cares cluster randomized control trial.

BACKGROUND: To fully leverage the potential of the early care and education (ECE) setting for childhood obesity prevention, initiatives must not intervene solely at the organizational level, but rather they should also address the health needs of the ECE workers. Workers suffer disproportionately high rates of obesity, and have reported low confidence in modeling and promoting healthy eating and activity behaviors. However, information regarding the effectiveness of improving ECE workers' health behaviors or whether such improvements elicit meaningful change in the ECE environment and/or the children in their care is limited. METHOD: The proposed study will integrate a staff wellness intervention into a nationally recognized, ECE obesity prevention initiative (Go NAPSACC). Go NAPSACC+ Staff Wellness program will be assessed using a clustered randomized controlled trial including 84 ECE centers, 168 workers, and 672 2-5-year-old children. Centers will be randomly assigned to 1) standard "Go NAPSACC" or 2) Go NAPSACC+ Staff Wellness. Outcome measures will assess impact on dietary intake and PA behaviors of 2-5-year-old children at 6 months (primary aim) and 12 months. Secondarily, we will compare the impact of the intervention on centers' implementation of healthy weight practices and the effect on ECE workers' diet quality and PA at 6- and 12 months. DISCUSSION: This trial expects to increase our understanding of how ECE worker's personal health behaviors impact the health behaviors of the children in their care and the ECE environment. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05656807, registered on 19 December 2022. Protocol version 1.0, 22 March 2023.

Physical activity maintenance among young adult cancer survivors in an mHealth intervention: Twelve-month outcomes from the IMPACT randomized controlled trial.

BACKGROUND: Most physical activity (PA) interventions in young adult cancer survivors (YACS) have focused on short-term outcomes without evaluating longer-term outcomes and PA maintenance. This study examined the effects of an mHealth PA intervention at 12 months, after 6 months of tapered contacts, relative to a self-help group among 280 YACS. METHODS: YACS participated in a 12-month randomized trial that compared self-help and intervention groups. All participants received an activity tracker, smart scale, individual videochat session, and access to a condition-specific Facebook group. Intervention participants also received lessons, tailored feedback, adaptive goal setting, text messages, and Facebook prompts for 6 months, followed by tapered contacts. Accelerometer-measured and self-reported PA (total [primary outcome], moderate-to-vigorous [MVPA], light, steps, sedentary behaviors) were collected at baseline, 6, and 12 months. Generalized estimating equation analyses evaluated group effects on outcomes from baseline to 12 months. RESULTS: From baseline to 12 months, there were no between- or within-group differences in accelerometer-measured total PA min/week, while increases in self-reported total PA were greater in the intervention versus self-help group (mean difference = +55.8 min/week [95% CI, 6.0-105.6], p = 0.028). Over 12 months, both groups increased accelerometer-measured MVPA (intervention: +22.5 min/week [95% CI, 8.8-36.2] vs. self-help: +13.9 min/week [95% CI, 3.0-24.9]; p = 0.34), with no between-group differences. Both groups maintained accelerometer-measured and self-reported PA (total, MVPA) from 6 to 12 months. At 12 months, more intervention participants reported meeting national PA guidelines than self-help participants (47.9% vs. 33.1%, RR = 1.45, p = 0.02). CONCLUSION: The intervention was not more effective than the self-help group at increasing accelerometer-measured total PA over 12 months. Both groups maintained PA from 6 to 12 months. Digital approaches have potential for promoting sustained PA participation in YACS, but additional research is needed to identify what strategies work for whom, and under what conditions.

Effect of an mHealth intervention on physical activity outcomes among young adult cancer survivors: The IMPACT randomized controlled trial.

BACKGROUND: Physical inactivity is common in young adult cancer survivors (YACS), but evidence regarding effects of physical activity (PA) interventions among YACS is limited. The IMproving Physical Activity after Cancer Treatment (IMPACT) trial evaluated a theory-based mobile PA intervention on total PA minutes/week (primary) and secondary outcomes (moderate-to-vigorous PA [MVPA], light PA, steps, sedentary behaviors) at 6 months in YACS. METHODS: YACS (N = 280) were randomized to an intervention group or self-help group. All participants received digital tools (activity tracker, smart scale, access to arm-specific Facebook group) and an individual video chat session. Intervention participants also received a 6-month program with behavioral lessons, adaptive goal-setting, tailored feedback, tailored text messages, and Facebook prompts. PA was assessed via accelerometry and questionnaires at baseline and 6 months. Generalized estimating equation analyses tested between-group differences in changes over time. RESULTS: Of 280 YACS, 251 (90%) completed the 6-month accelerometry measures. Accelerometer-measured total PA minutes/week changed from 1974.26 at baseline to 2024.34 at 6 months in the intervention (mean change, 55.14 [95% CI, -40.91 to 151.19]) and from 1814.93 to 1877.68 in the self-help group (40.94 [95% CI, -62.14 to 144.02]; between-group p = .84). Increases in MVPA were +24.67 minutes/week (95% CI, 14.77-34.57) in the intervention versus +11.41 minutes/week in the self-help (95% CI, 1.44-21.38; between-group p = .07). CONCLUSION: Although the intervention did not result in significant differences in total PA, the increase in MVPA relative to the self-help group might be associated with important health benefits. Future research should examine moderators to identify for whom, and under what conditions, the intervention might be effective. CLINICALTRIALS: gov Identifier: NCT03569605. PLAIN LANGUAGE SUMMARY: Physical inactivity is common in young adult cancer survivors. However, few interventions have focused on helping young adult cancer survivors to get more physical activity. The IMproving Physical Activity after Cancer Treatment trial compared a mobile health physical activity intervention with a self-help group on total amount of physical activity at 6 months in a nationwide sample of young adult cancer survivors. Intervention participants did not improve their total amount of physical activity, but they did increase their moderate-to-vigorous intensity physical activity by twice as much as the self-help participants. This increase in activity may be associated with health benefits.

Parent and child dietary changes in a 6-month mobile-delivered weight loss intervention with tailored messaging for parents.

Objective: To examine changes in parent and child dietary intake, associations between program adherence and parent dietary changes, and the association between parent and child dietary changes in a mobile-delivered weight loss intervention for parents with personalized messaging. Methods: Adults with overweight or obesity and who had a child aged 2-12 in the home were recruited for a randomized controlled trial comparing two types of dietary monitoring: calorie monitoring (Standard, n = 37) or "red" food monitoring (Simplified, n = 35). Parents received an intervention delivered via a smartphone application with lessons, text messages, and weekly personalized feedback, and self-monitoring of diet, activity, and weight. To measure associations between parent and child dietary changes, two 24-h recalls for parents and children at baseline and 6 months measured average daily calories, percent of calories from fat, vegetables, fruit, protein, dairy, whole grains, refined grains, added sugars, percent of calories from added sugars, and total Healthy Eating Index-2015 score. Results: Higher parent engagement was associated with lower parent percent of calories from fat, and greater days meeting the dietary goal was associated with lower parent daily calories and refined grains. Adjusting for child age, number of children in the home, parent baseline BMI, and treatment group, there were significant positive associations between parent and child daily calories, whole grains, and refined grains. Parent-child dietary associations were not moderated by treatment group. Conclusions: These results suggest that parent dietary changes in an adult weight loss program may indirectly influence child diet.

Recruitment of young adult cancer survivors into a randomized controlled trial of an mHealth physical activity intervention.

PURPOSE: Few studies have recruited young adult cancer survivors (YACS) from around the USA into remotely-delivered behavioral clinical trials. This study describes recruitment strategies used in the IMproving Physical Activity after Cancer Treatment (IMPACT) study, a 12-month randomized controlled trial of a mobile physical activity intervention for YACS. METHODS: We conducted formative work to guide development of recruitment messages and used a variety of methods and channels to recruit posttreatment YACS (diagnosed ages 18-39, participating in < 150 min/week of moderate-to-vigorous intensity activity). We used targeted social media advertisements, direct mailings, clinical referrals, and phone calls to potentially eligible individuals identified through local tumor registries. We also asked community organizations to share study information and advertized at a national conference for YACS. RESULTS: The final sample of 280 participants (23% identified as racial/ethnic minority individuals, 18% male, mean 33.4 ± 4.8 years) was recruited over a 14-month period. About 38% of those who completed initial screening online (n = 684) or via telephone (n = 63) were randomized. The top recruitment approach was unpaid social media, primarily via Facebook posts by organizations/friends (45%), while direct mail yielded 40.7% of participants. Other social media (paid advertisements, Twitter), email, clinic referrals, and conference advertisements each yielded 3% or fewer participants. The most cost-effective methods per participant recruited were unpaid social media posts and direct mailings. CONCLUSIONS: The IMPACT trial successfully met enrollment goals using a national strategy to recruit physically inactive YACS. Our approaches can inform recruitment planning for other remotely-delivered intervention trials enrolling YACS. TRIAL REGISTRATION: ClinicalTrials.gov NCT03569605 . Registered on 26 June 2018.

A pilot randomized trial of simplified versus standard calorie dietary self-monitoring in a mobile weight loss intervention.

OBJECTIVE: This study tested the efficacy of a lower-burden, simplified dietary self-monitoring approach compared with a standard calorie monitoring approach for self-monitoring adherence and weight loss in a mobile-delivered behavioral weight loss intervention. METHODS: Participants (n = 72) with overweight or obesity who had children 2 to 12 years of age living in the home were randomly assigned to a group that used simplified dietary self-monitoring of high-calorie foods (Simplified) or a group that tracked calories (Standard). Both groups received a wireless scale, Fitbit trackers, and a 6-month intervention delivered via a smartphone application with lessons, text messages, and weekly personalized feedback messages. RESULTS: Percentage weight loss at 6 months was 5.7% (95% CI: -8.3% to -3.2%) in the Standard group and 4.0% (95% CI: -5.7% to -2.3%) in the Simplified group, which was not significantly different. Similar proportions reached 5% weight loss at 6 months (43.2% in Standard and 42.9% in Simplified). There were no differences in number of dietary tracking days or change in average daily caloric intake between groups. CONCLUSIONS: Two mobile-delivered weight loss interventions produced clinically meaningful levels of weight loss at 6 months, with no differences in dietary tracking adherence or dietary intake. The results suggest that simplified monitoring of high-calorie foods could be a promising alternative to calorie monitoring.

Predictors and Outcomes of Digital Weighing and Activity Tracking Lapses Among Young Adults During Weight Gain Prevention.

OBJECTIVES: Self-monitoring is critical for weight management, but little is known about lapses in the use of digital self-monitoring. The objectives of this study were to examine whether lapses in self-weighing and wearing activity trackers are associated with weight and activity outcomes and to identify objective predictors of lapses. METHODS: Participants (N = 160, BMI = 25.5 ± 3.3 kg/m2 , 33.1 ± 4.6 years old) were drawn from a sample of young adults in the Study of Novel Approaches to Prevention-Extension (SNAP-E) weight gain prevention trial. Analyses evaluated associations between weighing and tracker lapses and changes in weight and steps/day during the first 90 days after receiving a smart scale and activity tracker. RESULTS: On average, participants self-weighed 49.6% of days and wore activity trackers 75.2% of days. Every 1-day increase in a weighing lapse was associated with a 0.06-lb gain. Lapses in tracker wear were not associated with changes in steps/day or weight between wear days. Weight gain predicted a higher likelihood of starting a lapse in weighing and tracker wear, whereas lower steps predicted a higher likelihood of a tracker lapse. CONCLUSIONS: Weight gain may discourage adherence to self-monitoring. Future research could examine just-in-time supports to anticipate and reduce the frequency or length of self-monitoring lapses.

Promoting physical activity in young adult cancer survivors using mHealth and adaptive tailored feedback strategies: Design of the Improving Physical Activity after Cancer Treatment (IMPACT) randomized controlled trial.

INTRODUCTION: Despite the health benefits of physical activity for cancer survivors, nearly 60% of young adult cancer survivors (YACS) are physically inactive. Few physical activity interventions have been designed specifically for YACS. PURPOSE: To describe the rationale and design of the IMPACT (IMproving Physical Activity after Cancer Treatment) trial, which tests the efficacy of a theory-based, mobile physical activity intervention for YACS. METHODS: A total of 280 physically inactive YACS (diagnosed at ages 18-39) will be randomized to a self-help control or intervention condition. All participants will receive an activity tracker and companion mobile app, cellular-enabled scale, individual videochat session, and access to a Facebook group. Intervention participants will also receive a 6-month mobile intervention based on social cognitive theory, which targets improvements in behavioral capability, self-regulation, self-efficacy, and social support, and incorporates self-regulation strategies and behavior change techniques. The program includes: behavioral lessons; adaptive goal-setting in response to individuals' changing activity patterns; tailored feedback based on objective data and self-report measures; tailored text messages; and Facebook prompts encouraging peer support. Assessments occur at baseline, 3, 6, and 12 months. The primary outcome is total physical activity min/week at 6 months (assessed via accelerometry); secondary outcomes include total physical activity at 12 months, sedentary behavior, weight, and psychosocial measures. CONCLUSIONS: IMPACT uniquely focuses on physical activity in YACS using an automated tailored mHealth program. Study findings could result in a high-reach, physical activity intervention for YACS that has potential to be adopted on a larger scale and reduce cancer-related morbidity. ClinicalTrials.gov Identifier: NCT03569605.

Examination of a partial dietary self-monitoring approach for behavioral weight management.

INTRODUCTION: Dietary self-monitoring in behavioral weight loss programmes traditionally involves keeping track of all foods and beverages to achieve a calorie deficit. While effective, adherence declines over time. WW™ (formerly Weight Watchers), a widely available commercial weight management programme, sought to pilot an approach that permitted participants to consume over 200 foods without monitoring them. METHODS: The current study used a pre-post evaluation design with anthropometric, psychosocial and physical health assessments at baseline, 3 and 6 months. RESULTS: Participants (N = 152) were, on average, 48.4 (±12.3) years old, with body mass index (BMI) of 32.8 (±4.8) m/kg2 and 94% female. Mean weight loss was 6.97 + 5.55 kg or 7.9 ± 6.1% of initial body weight (ps < .0001) at 6 months. One third (32.6%) of the sample lost 10% or more of initial body weight. Significant improvements in hunger, cravings, happiness, sleep, quality of life, aerobic stamina, flexibility and blood pressure were observed. Attendance at group meetings, as well as decreases in hunger, and fast food cravings from baseline to 3 months were associated with achieving 10% weight loss at 6 months (p < .01). CONCLUSIONS: Using an approach that does not require self-monitoring of all foods and beverages produced significant weight losses and other physical and psychosocial improvements.

Examining barriers, physical activity, and weight change among parents and nonparents in a weight loss intervention.

INTRODUCTION: Little is known about the influence of children in the home on physical activity and weight among adults in weight loss interventions. This study evaluated the association between number of children in the home, weight loss, and weight regain in a behavioural weight loss intervention, and whether those relationships were mediated in sequence by physical activity barriers and physical activity changes. METHODS: The sample included 267 participants from a randomized trial who had complete data on study variables. Variables at baseline, 6, and 18 months included physical activity barriers, objectively measured minutes of moderate-to-vigorous physical activity (MVPA), and objectively measured weight used to calculate percent weight loss (PWL) from baseline to 6 months and percent weight regained (PWG) from 6 to 18 months. RESULTS: A greater number of children in the home was associated with less PWL at 6 months. This relationship was mediated by greater baseline physical activity barriers and a smaller increase in MVPA at 6 months. The mediated effect was no longer significant when controlling for changes in dietary intake. There was no relationship between number of children and PWG from 6 to 18 months. CONCLUSIONS: Parents may need unique intervention supports to overcome barriers to initiation of physical activity to help them reach optimal weight loss.

Perceived Benefits and Barriers in the Mediation of Exercise Differences in Older Black Women with and Without Obesity.

OBJECTIVES: Weight control is an exercise benefit, important for older Black women, a group experiencing obesity disparities. We compared perceived exercise benefits and barriers between Black women with and without obesity and determined which mediated the weight group-exercise relationship. METHODS: A survey (n = 234) was administered to determine attitudinal agreement between weight groups (obese or non-obese). Multiple mediation analysis was used to investigate if attitudes mediated the weight group-exercise relationship. RESULTS: High agreement with all exercise benefits was observed between women with and without obesity. Compared with women without obesity, women with obesity were more likely to report the barriers of only exercising to lose weight (OR = 2.52, 95% CI 1.40-4.55), lack of will power (OR = 1.82, 95% CI 1.05-3.19), weight (OR = 3.04, 95% CI 1.34-6.83), and cost (OR = 2.14, 95% CI 1.02-4.47). Exercising to lose weight and lack of will power mediated the weight group-exercise relationship. CONCLUSIONS: Women largely agreed on the exercise benefits. Lack of will power and engaging in exercise only for weight loss were barriers that were more common among older Black women with obesity. The barriers partially explained the lower exercise engagement in women with obesity. Future work may address these barriers to increase exercise in older Black women.

Randomized trial comparing group size of periodic in-person sessions in a remotely delivered weight loss intervention.

BACKGROUND: Few randomized studies have examined differential effects of group size in behavioral weight control, especially in hybrid programs that include Internet treatment approaches. METHODS: Randomized controlled trial (n = 195) comparing a 4 month hybrid internet weight loss program coupled with monthly face to face groups of 100 persons (Large Group, LG; 1 group) or to the same approach with monthly groups of 20 persons (Small Group, SG; 4 groups). Repeated-measures mixed-model analysis with age and race as covariates were used to estimate primary (weight) and secondary outcomes, and to test group differences in change over time. RESULTS: The sample was 46.3 years old ±10.4, 90.3% female, and 51.9% non-white, with BMI 37.9 ± 8.4 kg/m2. Participants in the LG were more likely to return for the 4-month assessment visit than those in the SG (p = 0.04). Participants randomized to both the LG and SG conditions experienced significant WL over time (no between group difference: -4.1 kg and -3.7 kg, respectively) and weight loss was positively associated with attendance at monthly meetings and logins to the website. Satisfaction with the program was high and similar in both groups (94.4% reported that they were "satisfied" or "very satisfied"). CONCLUSIONS: Using a hybrid approach of in-person and online weight loss interventions may be an effective way to reach larger and more diverse populations. Delivering the face to face component of the intervention in groups larger than those traditionally delivered (20-25 people) could increase the cost-effectiveness of group-based behavioral weight loss interventions. CLINICAL TRIALS REGISTRATION NUMBER: NCT01615471 . Registered June 6, 2012. Registered retrospectively.

The influence of fathers on children's physical activity: A review of the literature from 2009 to 2015.

Parents are influential in promoting children's physical activity. Yet, most research has focused on how mothers influence children's activity, while little empirical attention has been devoted to understanding how fathers may influence children's activity. The purpose of this review was to summarize observational studies from 2009 to 2015 examining the influence of fathers on children's physical activity. A publicly available database, from a prior systematic review, containing information on 667 studies of parenting and childhood obesity from 2009 to 2015 was searched for potential studies. Studies were eligible if: 1) fathers were included as participants, 2) results were presented for fathers separate from mothers, 3) fathers' physical activity or physical activity parenting was assessed, and 4) child physical activity was measured. Ten studies met eligibility criteria. All studies were rated as fair quality. The majority of studies (n=8) assessed the relationship between father and child physical activity. Of 27 associations tested, 14 (52%) were significant, indicating a modest, positive relationship between father and child activity. Of the studies examining fathers' physical activity parenting (n=3), there were three significant associations out of 15 tested (20%) and no consistency among measured constructs. No differences were observed in the influence of mothers vs. fathers on children's physical activity. Limited evidence was available to examine moderating effects of child sex or age. Few studies have examined the effect of fathers on child physical activity and this relationship remains unclear. Future studies should target fathers for research and investigate specific pathways through which fathers can influence child activity.

A randomized trial to reduce sugar-sweetened beverage and juice intake in preschool-aged children: description of the Smart Moms intervention trial.

BACKGROUND: Obesity in young children remains a public health concern, and maternal weight is one of the strongest predictors of obesity in early childhood. However, parental adherence in interventions for young children is often low and existing programs have had mixed success. An innovative approach to treatment is needed that increases adherence among mothers and improves weight-related behaviors simultaneously in mothers and children. The objective of the Smart Moms randomized controlled trial (RCT) is to test the efficacy of a 6-month primarily smartphone-delivered program to reduce sugar-sweetened beverage and juice consumption among children ages 3-5 whose mothers are overweight or obese. This paper describes the study design and intervention. METHODS/DESIGN: Mother-child dyads were eligible if the mother was overweight or obese, owned a smartphone, and if the child was between the ages of 3-5 and consumed 12 oz or more per day of sugar-sweetened beverages (SSBs) and 100 % fruit juice. Participants were randomly assigned to the Smart Moms intervention or a waitlist control group. The intervention consisted of theoretically grounded and evidence-based behavioral strategies delivered through one group session, lessons on a mobile-optimized website, and text messages. Mothers submitted self-monitoring information via text message and received regular tailored feedback emails from interventionists. The primary outcome is change in child SSB and juice consumption and a secondary outcome is change in maternal weight. DISCUSSION: This Smart Moms study was designed to determine if a low-burden intervention delivered using mobile methods and targeted towards mothers could be effective at changing child sugar-sweetened beverage intake. Results will indicate if mobile-based methods can be a feasible way to engage mothers in family-based studies and will inform successful strategies to prevent childhood obesity through parent-targeted approaches. TRIAL REGISTRATION: Clinicaltrials.gov NCT02098902 (Registered March 25, 2014).

The Effect of Self-Efficacy on Behavior and Weight in a Behavioral Weight-Loss Intervention.

OBJECTIVE: To determine whether eating self-efficacy (ESE) and physical activity self-efficacy (PASE) are predictive of dietary intake, physical activity, and weight change within a behavioral weight-loss intervention, and whether dietary intake and physical activity mediate relationships between self-efficacy and weight change. METHOD: The study sample included 246 participants from a randomized trial with complete data on study variables at 12 months. ESE, PASE, calories consumed, minutes of moderate-to-vigorous physical activity (MVPA), and weight were measured at baseline, 6, and 12 months. RESULTS: ESE at baseline was associated with 12-month percent weight loss (PWL), and was mediated by average calories consumed at 6 and 12 months. Change in ESE from baseline to 6 months was associated with calories consumed at 12 months and 12-month percent weight loss, but the mediated relationship was not significant. Baseline PASE was not associated with average MVPA at 6 and 12 months or 12-month PWL, but change in PASE from baseline to 6 months was associated with 12-month PWL through its effect on MVPA at 12 months. CONCLUSION: Increases in ESE and PASE during the active phase of the intervention are predictive of dietary intake, physical activity and weight loss at later points, but further research should include explorations of the reciprocal relationship between behavior and self-efficacy to better inform intervention strategies that target self-efficacy and promote behavior change. (PsycINFO Database Record