An explanation for the accuracy of sensor-based measures of energy intake: Amount of food consumed matters more than dietary composition.

Understanding and intervening on eating behavior often necessitates measurement of energy intake (EI); however, commonly utilized and widely accepted methods vary in accuracy and place significant burden on users (e.g., food diaries), or are costly to implement (e.g., doubly labeled water). Thus, researchers have sought to leverage inexpensive and low-burden technologies such as wearable sensors for EI estimation. Paradoxically, one such methodology that estimates EI via smartwatch-based bite counting has demonstrated high accuracy in laboratory and free-living studies, despite only measuring the amount, not the composition, of food consumed. This secondary analysis sought to further explore this phenomenon by evaluating the degree to which EI can be explained by a sensor-based estimate of the amount consumed versus the energy density (ED) of the food consumed. Data were collected from 82 adults in free-living conditions (51.2% female, 31.7% racial and/or ethnic minority; Mage = 33.5, SD = 14.7) who wore a bite counter device on their wrist and used smartphone app to implement the Remote Food Photography Method (RFPM) to assess EI and ED for two weeks. Bite-based estimates of EI were generated via a previously validated algorithm. At a per-meal level, linear mixed effect models indicated that bite-based EI estimates accounted for 23.4% of the variance in RFPM-measured EI, while ED and presence of a beverage accounted for only 0.2% and 0.1% of the variance, respectively. For full days of intake, bite-based EI estimates and ED accounted for 41.5% and 0.2% of the variance, respectively. These results help to explain the viability of sensor-based EI estimation even in the absence of information about dietary composition.

School Nutrition Personnel Perceptions of School Salad Bars before and after COVID-19.

Many schools have salad bars as a means to increase students' fruit and vegetable intake. School nutrition programs experienced drastic changes to the school food environment due to COVID-19. The aim of the current study was to understand cafeteria personnel's experiences related to salad bar implementation before the COVID-19 pandemic and in the current school environment to inform efforts to enhance salad bar sustainability. Seven elementary schools (N = 30 personnel) installed salad bars prior to COVID-19; three of these schools (n = 13 personnel) re-opened salad bars after COVID-19. Cafeteria personnel completed surveys assessing their experiences with salad bars at both time points. Satisfaction with salad bar implementation and training was high pre- and post-COVID-19. Most agreed that salad bars increased students' fruit and vegetable intake, yet had concerns about cleanliness and waste. Perceived job difficulty increased post-COVID-19 (p = 0.01), and satisfaction with student salad bar training decreased (p = 0.001). Additional staff support and greater student training were needed post-COVID-19. Overall, salad bars were viewed favorably; however, more challenges and lower satisfaction were reported following COVID-19. Increasing support for cafeteria personnel is needed for salad bar sustainability and improving the school food environment.

Study design and rationale for TEENS+REACH: Evaluating ripple effects of a family-based lifestyle intervention to untreated family members.

Background: Understanding the effects of family-based lifestyle intervention beyond the treated adolescent is important, given that obesity is a familial disease and there are likely bidirectional relations between an adolescent's treatment success and broader household changes. However, it is unknown if recommended household-wide changes are adopted or if untreated family members experience weight-related benefits. Methods: TEENS + REACH leverages our ongoing randomized clinical trial of TEENS+, a family-based lifestyle intervention for adolescents with obesity, to determine: 1) if household-wide changes to the shared home environment are implemented, 2) if ripple effects to untreated family members are observed, and 3) whether these changes are predictive of adolescents' weight management success. TEENS + REACH will expand trial assessments to include comprehensive assessments of the shared home feeding, weight, and physical activity environment of the target adolescents. Specifically, we will enroll untreated children (8-17yrs) and caregivers living in the same household as the target parent/adolescent dyad (N = 60 families). At 0, 2, 4 (primary endpoint), and 8-months, the target parent/adolescent dyad and other untreated children and caregivers in the home will complete anthropometric assessments. Discussion: Results will determine the familial reach of TEENS+ and reveal potential mediators of treatment response, which can inform future efforts to optimize family-based lifestyle interventions. Trial registration: TEENS + REACH was retrospectively registered in Clinicaltrials.gov March 22, 2023 (NCT05780970) as an observational study ancillary to the TEENS + clinical trial, registered February 22, 2019 (NCT03851796).

Behavioral Intervention that Extends Sleep Duration Leads to Greater Self-Control in School-Aged Children.

OBJECTIVE: Short sleep and evening phase preference associate with impaired self-control, yet few studies have assessed the efficacy of sleep extension for improving this behavioral domain. Thus, this secondary analysis of a behavioral sleep intervention measured whether an intervention that enhanced children's sleep also affected self-control. Differences by chronotype were also explored. METHODS: Sixty-seven children (8-11 yr), who reportedly slept <9.5 hr/d, were randomized to either a control or sleep intervention condition (i.e., 4-session behavioral intervention to enhance sleep by 1-1.5 hr/night). Chronotype was assessed using the Child Chronotype Questionnaire at baseline, and self-control was assessed using the Self-Control Rating Scale (SCRS, a caregiver report) at baseline and 8 weeks postrandomization. Total sleep time (TST) was measured using wrist actigraphy for 1 week at both baseline and 8 weeks postrandomization. Partial correlations and mixed-model ANOVAs were used for statistical analyses, with age as a covariate. RESULTS: At baseline, children with shorter TST (r = -0.29, p = 0.02) and an evening preference (r = 0.26, p = 0.049) were perceived as having lower self-control by their caregivers. Significant condition*time interaction effects were found for TST (p < 0.001) and SCRS score (p = 0.046): From baseline to follow-up, children randomized to the sleep intervention exhibited a significant increase in TST and were perceived as having greater self-control by their caregiver; children randomized to the control condition exhibited no change in TST or in SCRS score. The condition*chronotype*time interaction effect was not significant. CONCLUSION: A brief sleep intervention that enhanced TST also resulted in enhanced caregiver reported self-control in school-age children. Results add to the growing evidence for the importance of sleep health in children.

Consistent exercise timing as a strategy to increase physical activity: A feasibility study.

Introduction/Purpose: Observational research suggests that consistent exercise timing could be leveraged to promote moderate-to-vigorous physical activity (MVPA) among adults with obesity. However, the feasibility and acceptability of prescribed consistent exercise timing in a free-living setting is unknown. The purpose of this study was to assess the feasibility and acceptability of prescribed consistent exercise timing in a free-living setting among inactive adults with obesity (primary) and to compare MVPA timing prescriptions and characterize exercise barriers/facilitators (secondary). Methods: Using a within-subjects design, inactive adults with obesity (n=15) were randomized in counterbalanced order to three 3-wk exercise timing conditions separated by 2-wk washout periods: 1) consistent morning, 2) consistent evening, and 3) choice timing (control). Feasibility was assessed using prespecified benchmarks. Acceptability and preferred timing were assessed with questionnaires post-intervention. Secondarily, exercise timing and MVPA were assessed via accelerometry and nightly surveys and barriers/facilitators were assessed with nightly surveys. Results: All feasibility benchmarks were achieved (e.g., timing adherence = 69.9% via accelerometry and 87.4% via self-report (target: ≥60%)). Consistent exercise timing was acceptable (mean rating = 3.7 of 5 (target: ≥3.5)). Choice was the most popular prescription. There were medium- to large-sized effects (partial η2 of 0.09-0.16) of condition on MVPA; MVPA was higher during the morning and evening conditions versus choice condition. Facilitators were similar across conditions, while some barriers were time specific. Conclusion: Prescribed exercise timing in a free-living setting appears feasible and acceptable. While choice timing was most preferred, consistent timing appeared most effective for increasing MVPA. Data warrant larger trials to test the efficacy and mechanisms of consistent exercise timing as a translational strategy for promoting MVPA. Pending findings from a fully powered randomized trial, practitioners interested in promoting MVPA among their patients or clients could consider encouraging exercise at a consistent time day-to-day.