BACKGROUND: Inconsistent results have been found in the literature on associations of greenness, or vegetation quantity, and physical activity. However, few studies have assessed associations between mobility-based greenness and physical activity from mobile health data from smartphone and wearable devices with fine spatial and temporal resolution. METHODS: We assessed mobility-based greenness exposure and wearable accelerometer data from participants in the US-based prospective Nurses Health Study 3 cohort Mobile Health (mHealth) Substudy (2018-2020). We recruited 500 female participants with instructions to wear devices over four 7-day sampling periods equally spaced throughout the year. After restriction criteria there were 337 participants (mean age 36 years) with n = 639,364 unique observations. Normalized Difference Vegetation Index (NDVI) data were derived from 30 m x 30 m Landsat-8 imagery and spatially joined to GPS points recorded every 10 min. Fitbit proprietary algorithms provided physical activity summarized as mean number of steps per minute, which we averaged during the 10-min period following a GPS-based greenness exposure assessment. We utilized Generalized Additive Mixed Models to examine associations (every 10 min) between greenness and physical activity adjusting for neighborhood and individual socioeconomic status, Census region, season, neighborhood walkability, daily mean temperature and precipitation. We assessed effect modification through stratification and interaction models and conducted sensitivity analyses. RESULTS: Mean 10-min step count averaged 7.0 steps (SD 14.9) and greenness (NDVI) averaged 0.3 (SD 0.2). Contrary to our hypotheses, higher greenness exposure was associated non-linearly with lower mean steps per minute after adjusting for confounders. We observed statistically significant effect modification by Census region and season. DISCUSSION: We utilized objective physical activity data at fine temporal and spatial scales to present novel estimates of the association between mobility-based greenness and step count. We found higher levels of greenness were inversely associated with steps per minute.

Objective

This study examines the extent to which insufficient sleep is associated with diet quality in students taking part in the Massachusetts Childhood Obesity Research Demonstration Project.

Methods

Data were collected in Fall 2012 for all 4th and 7th grade children enrolled in public schools in two Massachusetts communities. During annual body mass index (BMI) screening, students completed a survey that assessed diet, physical activity, screen time, and sleep. Of the 2456 enrolled students, 1870 (76%) had complete survey data. Generalized estimating equations were used to examine associations between sleep duration and dietary outcomes (vegetables, fruits, 100% juice, juice drinks, soda, sugar-sweetened beverages and water), accounting for clustering by school. Models were adjusted for community, grade, race/ethnicity, gender, television in the bedroom, screen time, and physical activity.

Results

In adjusted models, students who reported sleeping < 10 hours/day consumed soda more frequently (β = 0.11, 95% CI: 0.03, 0.20) and vegetables less frequently (β = -0.09, 95% CI: -0.18, -0.01) compared with students who reported ≥ 10 hours/day. No significant associations were observed between sleep duration and fruits, 100% juice, juice drinks or water.

Conclusions

In this population, insufficient sleep duration was associated with more frequent soda and less frequent vegetable consumption. Longitudinal research is needed to further examine these relationships.

Background and objective

Associations of inadequate sleep with numerous health outcomes among youth necessitate identifying its modifiable determinants. Television (TV) has been associated with sleep curtailment, but little is known about small screens (eg, smartphones), which can be used in bed and emit notifications. Therefore, we examined associations of different screens in sleep environments with sleep duration and perceived insufficient rest or sleep.

Methods

Participants included 2048 fourth- and seventh-graders participating in the Massachusetts Childhood Obesity Research Demonstration Study in 2012 to 2013. Using linear and log binomial regression, we examined cross-sectional associations of small screens and TVs in sleep environments and screen time with weekday sleep duration and perceived insufficient rest or sleep in the past week.

Results

Children who slept near a small screen (compared with never) reported 20.6 fewer minutes of sleep (95% confidence interval [CI], -29.7 to -11.4) and had a higher prevalence of perceived insufficient rest or sleep (prevalence ratio, 1.39; 95% CI, 1.21 to 1.60). Children who slept in a room with a TV (compared with no TV) reported 18.0 fewer minutes of sleep (95% CI, -27.9 to -8.1). TV or DVD viewing and video or computer game playing were associated with both sleep outcomes (P < .01). Some associations were stronger among Hispanic, non-Hispanic black, and older children (P < .05 for heterogeneity).

Conclusions

Sleeping near a small screen, sleeping with a TV in the room, and more screen time were associated with shorter sleep durations. Presence of a small screen, but not a TV, in the sleep environment and screen time were associated with perceived insufficient rest or sleep. These findings caution against unrestricted screen access in children's bedrooms.

Background

Childhood obesity is highly prevalent, is associated with both short- and long-term adverse outcomes, disproportionately affects racial/ethnic minority and economically deprived children, and represents a major threat to public health. Among the most promising approaches for its prevention and management are multilevel, multisector strategies.

Methods/design

The Massachusetts Childhood Obesity Research Demonstration (MA-CORD) Study was a comprehensive, systematic intervention to prevent and reduce childhood obesity among low-income children ages 2-12 years in two selected cities in Massachusetts. Building on the Obesity Chronic Care Model, MA-CORD expanded a state public health department community-level obesity prevention initiative that incorporated evidence-based interventions in primary healthcare, the Women, Infants, and Children program, early care and education, schools/afterschool programs, as well as community-wide programs to improve food, beverage, physical activity (PA), and messaging environments. The study used a combination of pre- and post-time series and quasi-experimental designs to examine the extent to which the intervention resulted in changes in BMI, individual-level lifestyle behaviors, satisfaction with healthcare services, and quality of life among children, as well as changes in health policies, programs, and environments in the two intervention cities, compared to a comparison city. The intervention period was 2 years.

Conclusions

MA-CORD will determine the extent to which a multisetting, multilevel intervention that integrates activities in primary care with broader public health interventions in schools, early care and education, and the community at large can improve children's dietary and PA behaviors and ultimately reduce obesity in low-income children.

Objective

To examine changes in prevalence of obesity and target health behaviors (fruit, vegetable, and beverage consumption; physical activity; screen time; sleep duration) among students from communities that participated in the Massachusetts Childhood Obesity Research Demonstration (MA-CORD) project compared to controls.

Methods

MA-CORD was implemented in two low-income communities. School-level prevalence of obesity among students in first, fourth, and seventh grades was calculated for the intervention communities and nine matched control communities pre and post intervention. Fourth- and seventh-grade students' self-reported health behaviors were measured in intervention communities at baseline and post intervention.

Results

Among seventh-graders (the student group with greatest intervention exposure), a statistically significant decrease in prevalence of obesity from baseline to post intervention in Community 2 (-2.68%, P = 0.049) and a similar but nonsignificant decrease in Community 1 (-2.24%, P = 0.099) was observed. Fourth- and seventh-grade students in both communities were more likely to meet behavioral targets post intervention for sugar-sweetened beverages (both communities: P < 0.0001) and water (Community 1: P < 0.01; Community 2: P = 0.04) and in Community 2 for screen time (P < 0.01).

Conclusions

This multisector intervention was associated with a modest reduction in obesity prevalence among seventh-graders in one community compared to controls, along with improvements in behavioral targets.

Introduction

Although evidence-based interventions to prevent childhood obesity in school settings exist, few studies have identified factors that enhance school districts' capacity to undertake such efforts. We describe the implementation of a school-based intervention using classroom lessons based on existing "Eat Well and Keep Moving" and "Planet Health" behavior change interventions and schoolwide activities to target 5,144 children in 4th through 7th grade in 2 low-income school districts.

Methods

The intervention was part of the Massachusetts Childhood Obesity Research Demonstration (MA-CORD) project, a multisector community-based intervention implemented from 2012 through 2014. Using mixed methods, we operationalized key implementation outcomes, including acceptability, adoption, appropriateness, feasibility, implementation fidelity, perceived implementation cost, reach, and sustainability.

Results

MA-CORD was adopted in 2 school districts that were facing resource limitations and competing priorities. Although strong leadership support existed in both communities at baseline, one district's staff reported less schoolwide readiness and commitment. Consequently, fewer teachers reported engaging in training, teaching lessons, or planning to sustain the lessons after MA-CORD. Interviews showed that principal and superintendent turnover, statewide testing, and teacher burnout limited implementation; passionate wellness champions in schools appeared to offset implementation barriers.

Conclusion

Future interventions should assess adoption readiness at both leadership and staff levels, offer curriculum training sessions during school hours, use school nurses or health teachers as wellness champions to support teachers, and offer incentives such as staff stipends or play equipment to encourage school participation and sustained intervention activities.