Sleep duration associates with moderate-to-vigorous intensity physical activity and body fat in 1- to 3-year-old children

Longitudinal Change in Physical Activity in Children 6 to 36 Months of Age

OBJECTIVE

To describe the developmental pattern for physical activity (PA) in children 6-36 months of age and to identify factors that are longitudinally associated with PA as children transition from infancy to preschool age.

STUDY DESIGN

The study employed a prospective longitudinal design with baseline data collected when children were approximately 6 months of age. Mothers and infants (n = 124) were recruited through community and educational settings in South Carolina. Data were collected at 6-month intervals from 6 to 36 months. PA was measured via accelerometry. Mothers completed questionnaires that assessed independent variables, including parent characteristics, the child's sex, race, and ethnicity, birth/delivery type, motor milestones, sleep habits, dietary practices, childcare setting, and home environmental factors. Trained research staff administered anthropometric measures and assessed motor developmental status. Growth curve models described the age-related pattern for PA and evaluated relationships between independent variables and change in PA.

RESULTS

PA increased by approximately 45% between 6 and 36 months of age and followed a curvilinear pattern, with most of the increase occurring between 6 and 24 months. The child's exposure to television/electronic media was negatively associated with change in PA, and the presence of older siblings in the home was positively associated with change in PA.

CONCLUSIONS

As children develop from infancy to early childhood, their PA increases substantially, with most of the increase occurring by 24 months of age.

Longitudinal Associations Between Physical Activity and Sleep Duration in Infants and Toddlers

PURPOSE

This study examined longitudinal associations between average physical activity (PA) levels in children and their sleep duration, and whether changes in PA levels are associated with their sleep duration.

METHODS

Data were collected on 108 children at 4 time points: when children were 6, 12, 18, and 24 months of age (44% female, 50% Non-Hispanic White). PA was assessed using accelerometry. Children's daytime, nighttime, and 24-hour sleep duration were measured with actigraphy. Linear mixed model analyses estimated the associations between average PA levels over time and changes in PA over time, treating each sleep duration variable as an outcome in separate linear mixed model analyses.

RESULTS

Children with higher total PA levels slept less during the day compared with children with lower total PA levels over the 2-year period. The strength of the relationship between a child's PA levels and their 24-hour sleep duration decreased as they approached 24 months of age.

CONCLUSIONS

The results suggest that while PA may be developmentally beneficial overall, it appears that its relationship with sleep duration is not clinically relevant in very young children.

Exploring Factors Associated With Accelerometer Validity Among Ethnically Diverse Toddlers

PURPOSE

Studying physical activity in toddlers using accelerometers is challenging due to noncompliance with wear time (WT) and activity log (AL) instructions. The aims of this study are to examine relationships between WT and AL completion and (1) demographic and socioeconomic variables, (2) parenting style, and (3) whether sedentary time differs by AL completion.

METHODS

Secondary analysis was performed using baseline data from a community wellness program randomized controlled trial for parents with toddlers (12-35 mo). Parents had toddlers wear ActiGraph wGT3x accelerometers and completed ALs. Valid days included ≥600-minute WT. Analysis of variance and chi-square analyses were used.

RESULTS

The sample (n = 50) comprised racial and ethnically diverse toddlers (mean age = 27 mo, 58% male) and parents (mean age = 31.7 y, 84% female). Twenty-eight families (56%) returned valid accelerometer data with ALs. Participants in relationships were more likely to complete ALs (P < .05). Toddler sedentary time did not differ between those with ALs and those without.

CONCLUSIONS

We found varied compliance with WT instructions and AL completion. Returned AL quality was poor, presenting challenges in correctly characterizing low-activity counts to improve internal validity of WT and physical activity measures. Support from marital partners may be important for adherence to study protocols.

The Perspectives of Preservice Kinesiology Students Concerning Autism and Physical Activity: Differences by Adapted Physical Activity Exposure

BACKGROUND

This study investigated the effect of an adapted physical activity (APA) course on knowledge and perceptions of preservice trainees regarding physical activity (PA) and autism spectrum disorder in 3 areas: knowledge/perspectives, importance and ease of improving developmental domains, and importance and ease of improving motor skills.

METHODS

Four hundred upper-level undergraduate students were recruited to participate in this survey-based study (251 APA students and 149 non-APA students participated). Survey data were analyzed using multivariate analyses of variance.

RESULTS

Participants estimated that the moderate to vigorous PA recommendations are 39.34 minutes per day, that 46.65% of moderate to vigorous PA occurs during school, and that 61.03% of children have motor difficulties. Participants perceived activities of daily living, sleep habits, and heart health as the easiest domains to improve, and problem behaviors, social skills, and self-esteem as the most difficult domains to improve. Knowledge/perspectives regarding autism spectrum disorder and PA were different by APA exposure (F12,324 = 3.11, P < .001). Differences included self-efficacy in providing PA advice, knowledge of PA guidelines, and willingness to provide motor assessment referrals. Students differed by APA exposure in the importance of developmental domains (F8,381 = 4.37, P < .001) but not ease of improving those domains.

CONCLUSION

Results suggest that APA education and contact with children with disabilities improves self-efficacy, perspectives, and knowledge of PA and motor concerns in children with autism spectrum disorder.

Measuring PROMIS® Physical Activity and Sleep Problems in Early Childhood

OBJECTIVE

Physical activity (PA) and sleep are leading health indicators for individuals of all ages. Monitoring young children's PA and sleep using psychometrically sound instruments could help facilitate timely interventions to promote healthy development. This article describes the development of the PROMIS® Early Childhood (EC) Parent Report Physical Activity (PA) and Sleep Problems (SP) measures for children aged 1-5 years.

METHODS

Item pools were generated by interviewing parents, input from content experts, and literature review. Data from a U.S. general population sample were used to determine factor structures of item pools via factor analytic approaches, estimate item parameters via item response theory (IRT) models, and establish norms. Pearson correlations were used to evaluate across-domain associations. Analysis of variance was used and known-groups' validity of PA and SP by comparing their scores to PROMIS EC Parent Report Global Health: child's physical, emotional, and mental conditions.

RESULTS

Initial item pools consisted of 19 and 26 items for PA and SP, respectively. Factor analyses' results supported unidimensionality of 5 and 16 items measuring PA and SP, respectively, which were then calibrated using IRT. Norms were established by centering to a probability-based U.S. general population. Computerized adaptive testing algorithms were established. Some analyses supported initial measure validity.

CONCLUSIONS

The PROMIS EC PA calibrated scale and SP item banks are user-friendly and brief, yet produce precise scores. Both measures enable psychometrically sound assessment of PA behavior and sleep problems. Future studies to comprehensively evaluate the validity of these two measures are warranted.

Gender Difference and Correlates of Physical Activity Among Urban Children and Adolescents in Ethiopia: A Cross-Sectional Study

Background

Studies indicate that children and adolescent populations in most countries show a low level of physical activity (PA) and an increasing prevalence of obesity. Addressing gender disparity in PA is the main element of public health programs. There is currently a paucity of studies, particularly, in developing countries that investigate gender differences and correlates of PA among children and adolescents.

Objective

The study is aimed to assess the gender difference and correlates of PA among children and adolescents in Ethiopia.

Methods

An observational population-based cross-sectional study was conducted in representative samples of children and adolescents in the capital city of Ethiopia, Addis Ababa. Multivariable logistic regression models with robust estimation of SEs were fitted to predict the odds ratios (ORs) and 95% CIs.

Results

A total of 632 children and adolescents-parent dyads were included in the study. More boys than girls (17.0 and 11.7%) were engaged in moderate intensity PA 3 days a week or more (p = 0.057). Age, mothers working in a private business, attending public schools, longer sleep duration, and being taught the benefits of PA were positively associated with meeting moderate-to-vigorous PA (MVPA) in both sexes combined and in a sub-sample of boys. Furthermore, an inverse association was found between overweight/obesity and MVPA in the overall children and girls as well. For moderate PA (MPA); the age of the children, maternal education and occupation, school type, overweight/obesity, and sleep duration on school nights were significant correlates among the studied children.

Conclusions

The present study provided evidence of several correlates identified associated with meeting MVPA and MPA in both sexes combined. Girls are less likely than boys to engage in PA. Therefore, there is a need to take into perspectives the provision of a comprehensive multifaceted health behavior modification and interventions, such as focused and regular physical education in schools.

Temporal relationships between device-derived sedentary behavior, physical activity, and sleep in early childhood

STUDY OBJECTIVES

Understanding the ideal composition of a child's day requires a better understanding of the relations between wake behaviors (sedentary behavior [SB], physical activity [PA]) and sleep. Here, we examine between- and within-person temporal associations between daytime wake behaviors and overnight sleep in early childhood, an important age when healthy behaviors are initiated and 24-hour behaviors are largely determined by caregivers.

METHODS

Daily, repeated measures of wake behavior and overnight sleep were assessed via wrist-worn actigraphy (mean = 9 days/nights) in 240 children (50.8 ± 9.8 months). Multilevel models with lagged effects were used to examine the temporal associations between wake and overnight sleep measures and adjusted for daily nap duration, age, sex, and socioeconomic status.

RESULTS

Between-person associations for sleep outcomes were negative between moderate-to vigorous-intensity PA (MVPA) and total activity for sleep efficiency (SE). Between-person associations for wake outcomes were positive between sleep duration and light PA, and negative between SE and both MVPA and total PA. When children obtained higher SE relative to their individual average, they were more likely to engage in less SB and greater MVPA and total PA the next day.

CONCLUSIONS

Generally, days with greater activity or sleep were not associated with greater subsequent sleep or PA. Most subsequent behaviors were not influenced by children achieving higher activity or sleep relative to their individual average levels, although higher SE was beneficially associated with next day wake behaviors. Future analyses with young children should consider within-person associations and could investigate lagged effects beyond one day.

A Systematic Review of the Relationships Between Physical Activity and Sleep in Early Childhood

The aim of this systematic review was to examine the associations between physical activity and sleep in children aged less than 6 years. Articles were included if participants were primarily aged less than 6 years and study designs were observational or experimental. Study characteristics were extracted, and the Grading Recommendations Assessment, Development and Evaluation framework was used to assess study quality. Thirty-six studies (16 sleep, 16 physical activity, and three fitness outcomes) from 18 countries reported in 29 articles were included. The majority of sleep and physical activity outcome studies reported mixed effects with very low to low quality of evidence. Fitness outcome studies were limited, and therefore, evidence was insufficient. The high prevalence of mixed and null results could be related to study limitations. Importantly, this review points to the critical need for higher quality studies of sleep and physical activity in young children, which would support health recommendations and intervention strategies for healthier child development.

Insufficient sleep during infancy is correlated with excessive weight gain in childhood: a longitudinal twin cohort study

STUDY OBJECTIVES

To examine total sleep duration in infancy and the associations of insufficient sleep duration with later weight gain and the risk of overweight in a longitudinal twin cohort study.

METHODS

The data for this study are from the Longitudinal Twin Study (LoTiS), a twin-pregnancy birth cohort study that was carried out in China (n = 186 pairs). The sleep data were collected at 6 months using the Brief Infant Sleep Questionnaire that was completed by parents with the assistance of a research assistant. Anthropometric data were obtained from the children's health clinic records at 6, 12, 18, and 24 months.

RESULTS

There were no significant differences between infants with insufficient sleep and those with sufficient sleep in terms of height, weight, body mass index, incidence of overweight, and body fat mass, while infants with insufficient sleep duration were predisposed to gain excessive weight from 6 to 12 and 6 to 18 months of age (all P < .05). After adjusting for confounding variables, insufficient sleep duration was found to be correlated with excessive weight gain from 6 to 18 months of age (odds ratio: 3.47; 95% confidence interval, 1.23-9.78). The relationship was more pronounced in monozygotic twins than in dizygotic twins.

CONCLUSIONS

Insufficient total sleep duration at the age of 6 months is correlated with the risk of excessive weight gain at 18 months of age in twins, particularly in monozygotic twins.

CLINICAL TRIAL REGISTRATION

Registry: Chinese Clinical Trial Register; Name: Unraveling the complex interplay between genes and environment in specifying early life determinants of illness in infancy: a longitudinal prenatal study of Chinese Twins. URL: http://www.chictr.org.cn/showproj.aspx?proj=13839; Identifier: ChiCTR-OOC-16008203.

CITATION

Yu J, Jin H, Wen L, et al. Insufficient sleep during infancy is correlated with excessive weight gain in childhood: a longitudinal twin cohort study. J Clin Sleep Med. 2021;17(11):2147-2154.

Infant Leg Activity Intensity Before and After Naps

Wearable sensors are being used to measure intensity of infant physical activity across full days. The variability of infant activity intensity within and across days is important to study given the potential impact of physical activity on developmental trajectories. Using retrospective data, we analyzed the intensity of leg movements in 10 typically-developing infants before and after naptimes. Leg movement data were captured from 20 minutes before and after multiple events of naps across seven days for each infant. We hypothesized that leg movement intensity would be lower before a nap than after a nap potentially due to lower arousal and increased fatigue prior to attaining sleep. However, our results showed that leg movement intensity was not significantly different when comparing the 20-minute period pre- and post-naps (F(1,7)=3.91, p=0.089, ηp 2=0.358). Our results are a first step in describing patterns of infant activity across days and highlights the need for further research regarding infant energy expenditure and physical activity.