Temperament and vocabulary knowledge are indicators of behavioral and cognitive development in early childhood and have independently been linked to 24-hour movement behaviors (sedentary time [SED], light physical activity [LPA], moderate-to-vigorous physical activity [MVPA], and sleep). Movement behaviors may have interactive effects on these developmental markers. 

Purpose: To examine predicted changes in preschool-aged children’s temperament and vocabulary knowledge when reallocating time between movement behaviors using compositional isotemporal substitution. 

Methods: This cross-sectional analysis was conducted in data from 206 children (50.9±9.5 months; 46.1% female). Movement behaviors were assessed with wrist-worn accelerometers for up to 15 days (9.7±3.3 days; 9.8±3.3. nights). Indicators of child temperament (surgency extroversion, negative affectivity, and effortful control) were derived from the Child Behavior Questionnaire Very Short form completed by caregivers. The Peabody Picture Vocabulary Test (PPVT) was used to assess vocabulary knowledge. First, baseline linear regression models predicted estimates of temperament and vocabulary outcomes with 24-hour movement behaviors as isometric-log ratio coordinates using age and sex as covariates. Next, models with new compositions that included one-to-one time reallocations predicted new outcome estimates, which were then compared to baseline predictions. 

Results/Findings: When theoretical time reallocations up to 60 minutes (in 10-minute increments) were examined, there were no significant differences in estimates of temperament. However, adding time to sleep at the expense of SED or MVPA and adding time to LPA at the expense of SED or MVPA was associated with increased estimates of PPVT score. For example, reallocating 20 minutes of SED to sleep, MVPA to sleep, SED to LPA, and MVPA to LPA were associated with increased PPVT scores of 1.7 (95% CI = 0.4 to 3.1), 3.0 (95% CI = 0.5 to 5.5), 2.4 (95% CI = 0.6 to 4.2), and 3.7 (95% CI = 0.6 to 6.9), respectively. Estimates of change in PPVT scores for these behaviors increased with greater time reallocations. 

Conclusions: Interaction of sleep and wake behaviors had no effect on temperament but did contribute to vocabulary knowledge. As such, interventions aiming to improve vocabulary knowledge in preschoolers may consider approaches to increase sleep and LPA.

Mothers of a child with a special health care need have worse mental and physical health compared to other mothers. Physical activity (PA) may improve depressive symptoms (DS) and overall health; however, little is known about PA in mothers who have a child with a special health care need. Purpose: The aim of this study was to examine acceptable types of PA in mothers who have a child with a special health care need to improve DS and inform future interventions.  Methods: Mothers completed a survey (n=348; age=39.3±7.3 yrs; white=92%; Midwest=80.1%; employed=59.2%; prenatal/at birth diagnosis=51.7%) that assessed demographics, general child information, PA and PA preference, depression, and emotional health. Descriptive statistics were calculated for quantitative questions. Qualitative responses were gathered and categorized to understand interest and type of PA participation. Results: Mothers reported meeting PA guidelines before pregnancy (50.9%), during pregnancy (30.7%), postpartum (30.2%), and currently (39.1%). A majority (59.8%) of mothers reported DS. Over 77% (n=268) of mothers participated in some type of PA, and did so to help with DS (37%), better overall health (76%), better quality of life (77%), and weight loss (57%). Mothers who engaged in PA (37%) primarily used walking (65.6%), house cleaning (56%), yoga (40%), strength training (38%), jogging (33%), and other (23%) to cope with depression. However, 85% of all participating mothers were interested in using PA (85%) and yoga (71%), as a means to cope with DS. Qualitative responses for why mothers participate in PA included: cannot die due to my son’s needs, have to remain fit/strong to physically care for my child, to be strong enough to care for my daughter, self-love, and for personal time away.  Conclusions: The quantitative and qualitative data suggest the majority of mothers’ view PA as a means to increase health and fitness to meet the needs of their children with a special health care need, though fail to meet the levels of PA associated with DS reduction. Future interventions and public health initiatives should consider population-specific PA norms, PA interests and PA rationale to increase the salience of meeting PA recommendations in this vulnerable population.  

Purpose:  Active transportation has multiple health, environmental and economic benefits. Considering its wide benefits, it is relevant to determine the national situation of this behavior to guide the design of initiatives that support walking and cycling promotion. In Colombia, active transportation has been assessed in multiple local and regional studies, with widely differing findings, but national data on active transportation are scarce. The 2015 National Survey of Nutrition assessed the engagement in active transportation to/from school in a nationally representative sample for the first time in the country. This paper aims to describe the prevalence and factors associated with active transportation to/from school among Colombian children and adolescents.

Methods: We analyzed nationally representative data from the National Survey of Nutrition 2015, a cross-sectional survey with a stratified, multistage probability cluster sampling design. The sample for this analysis included 2,867 preschoolers (3-5 years), 4,005 school-aged children (6-12 years), and 4,594 adolescents (13-17 years). Active transportation to/from school was reported by parents for pre-schoolers and school-aged children and self-reported by adolescents. Descriptive statistics were calculated, and prevalence ratios were estimated using Poisson regression multivariable models with robust variance. All the analyses were conducted using STATA 14.0 with the SVY module for complex samples to take into account the characteristics of the study design.

Results: Approximately 70% of Colombian children and adolescents reported engaging in active transportation to/from school over the last week. There were no differences by sex among pre-schoolers nor school-aged children. Fewer adolescent females than males used active transportation. Children and adolescents with car availability at the household were less likely to walk or cycle to/from school. Pre-schoolers and school-age children living in Bogota were more likely to report active transport than children from other regions and school-age children and adolescents with a lower wealth index were more likely to use active transportation than their counterparts. 

Conclusions: The wealthiest children and adolescents, adolescents from rural areas, and female adolescents should be a focus for future interventions. Actions need to be implemented to maintain the high involvement in active transportation to/from school in Colombia.

Purpose: To determine if there is an association between physical activity (PA) and gut bacterial microbiota in a cohort of 10-year-old children from the racially and socioeconomically diverse Wayne County Health Environment Asthma and Allergy Longitudinal Study (WHEALS) birth cohort.

Methods: At 10 years of age, WHEALS children were invited to complete a research clinic visit that included anthropometric assessment (height, weight) and to complete a questionnaire. PA was assessed using the Block Physical Activity Screener (BKPAS), which provides minutes/day PA variables that were used to determine whether the child was meeting PA recommendations (i.e., 60 minutes of moderate-to-vigorous PA). Children also provided a stool sample; 16S rRNA sequencing was used to profile the bacterial gut microbiota present.  Differences in alpha diversity metrics (richness, Pielou’s evenness, and Faith’s phylogenetic diversity) by PA were tested using linear regression, while beta diversity (unweighted and weighted UniFrac) was tested using PERMANOVA (p<0.05 considered significant). Taxonomic testing was performed using DESeq2, with False Discovery Rate adjusted p<0.05 considered significant. 

Results/findings: The analytic sample included 321 children with both PA and 16S sequencing data (mean age (SD) =10.2(0.8) years; 54.2% male; 62.9% African American). After adjusting for covariates (maternal education, household income, location of residence, sex, child race, breastfeeding status at 1-month, BMI category at age 10, and diet), PA was not significantly associated with stool richness, evenness, or diversity at age 10 (all p≥0.28). However, estimated daily moderate PA minutes (Weighted UniFrac R2=0.007, p=0.045) as well as meeting recommendations of PA (Weighted UniFrac R2=0.014, p=0.001) were significantly associated with distinct gut bacterial composition. These compositional differences were partly characterized by an increased abundance of Prevotella_2 as well as specific Christensenellaceae_R-7_group OTUs in children with greater PA. 

Conclusions:  Although PA has recently been established as a probable modulator of the gut microbiome, alterations in the abundance of specific taxa at different life stages remains unclear. The results of this study suggest that children who meet recommendations of PA have alterations in their gut microbiome.  Whether this translates to reduced risk of obesity or associated metabolic diseases requires additional study.

Purpose: Low levels of physical activity in children correspond to low physical fitness. Children with obesity have lower fitness; however little is known about the obesity-fitness relationship as the severity of obesity increases. To address this gap, we examined the longitudinal association between weight status and fitness in a large, diverse sample of New York City school children.

Methods: A prospective cohort analysis was conducted with New York City public school children in grades 4-12 from the NYC Fitnessgram dataset (11 cohorts; 2006-2017). The NYC Fitnessgram includes annual assessments of weight and fitness collected during physical education classes. Weight status was assessed using the Centers for Disease Control growth charts and classes of obesity were defined using body mass index relative to the 95^th percentile. Fitness was measured as a composite fitness z-score to account for expected improvements with increasing age and sex. The composite score was based on measures of aerobic capacity assessed with the Progressive Aerobic Cardiovascular Endurance Run, and muscular strength and endurance assessed with the push-up and curl-ups tests. Demographic factors including child sex, grade, race/ethnicity, poverty, and country of birth were extracted from enrollment records. Longitudinal mixed models with random-intercepts were developed to test the weight class-fitness association.  Secondary models tested for interaction effects of demographic factors on the weight class-fitness association.

Results/findings: The sample included 1,114,333 children (50% male, 37.5% Hispanic, 26.5% non-Hispanic Black, 10.9%, 3.6%, and 1.3% class I, II and III obesity, respectively). Compared to children with healthy weight, increasing level of obesity was associated with decreased fitness: overweight (β=-0.71, 95% CI: -0.71, -0.70), class 1 obesity (β = -1.41, 95% CI: -1.41, -1.40), class 2 obesity (β = -2.12, 95% CI: -2.13, -2.11), and class 3 obesity (β = -2.82; 95% CI: -2.84, -2.80). Interaction models showed the magnitude of the inverse dose response pattern of association between weight status and fitness increased in magnitude for male, high school, Hispanic, lower income and US-born children. 

Conclusions: Given independent effects of fitness on health outcomes, targeted clinical and public health interventions are needed to improve the fitness of children with obesity.

Methods: This multi-component home-based PA intervention enrolled youth from five high-risk middle schools in Philadelphia in the summer of 2020. The intervention included 1) three bi-weekly home deliveries of program materials, 2) access to a private YouTube channel with sport and exercise videos, and 3) daily text-messages from a health coach. Home deliveries included sports equipment (e.g., basketball, yoga mat), fresh produce, recipes, and handouts to guide goal-setting and self-monitoring. Parents and youth completed baseline and follow-up surveys to assess program satisfaction, YouTube analytics examined online engagement, and youth self-reported outcomes using validated measures.

Results/findings: A total of 67 youth were enrolled in the program (12.3 (1.2) years, 91.0% Black/African American, 38.8% female). Fifty parents (74.6%) and 34 children (47.8%) completed surveys at the end of the program. A majority of parents (86.0%) reported the overall program as “helpful” or “very helpful” for their child’s health over the summer. Parents also rated the following as “helpful” or “very helpful” in response to the program components: the delivery of sports equipment (98.0%), the delivery of fresh produce and recipes (98.0%), and text-messages from health coaches (86.0%). Most parents (96.0%) and youth (83.8%) expressed interest in participating in the program again. YouTube videos were viewed 1,513 times, but students only watched 16.8% of each video for an average time of 4.3 minutes. Though response rate was low, youth reported a significant improvement in PA (M(sd)=4.2(7.9), p<0.004) and PA self-efficacy (M(sd)=0.4(1.0), p<0.03).

Conclusion: Provision of program materials (e.g., sports equipment) were reported by parents to be particularly helpful components of the Camp from Home program. Youth engagement with digital components was low, but overall program acceptance was high. Youth reported increases in PA and PA self-efficacy, but future studies are needed to examine the most effective intervention components and mechanisms of behavior change for this high-risk group.