Abstract
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.
The objective was to determine if, in preschool-aged children, (1) nap habituality is associated with sedentary time and physical activity (movement behaviors), (2) nap physiology is associated with ...movement behaviors, and (3) if missing a nap, compared to taking a nap, affects movement behaviors on the same day and subsequent day. A within-subjects (44 children; 4.2 ± 0.6 years; 55.6% female), at-home study examined two experimental conditions (one afternoon each of nap- and wake-promotion with order counterbalanced) one week apart. Movement behaviors were derived from wrist-worn actigraphy (12.1 ± 3.1 days). Average movement behaviors were calculated from the overall study period with experimental days excluded. Movement behaviors were also extracted for the same day and the subsequent day of the two experimental conditions. Polysomnography was recorded during the nap-promoted condition. Children were classified as non-, intermediate-, or habitual-nappers. Although average movement behaviors were different between nap habituality groups, differences were not significant. There were no associations between movement behaviors and nap sleep stages, and no effects for nap condition or condition by nap habituality on same or next day movement behaviors. Findings do not suggest that naps and movement behaviors are related in children. Although a single missed nap was not detrimental to same or next day movement behaviors, future studies should explore effects of multiple days of subsequent nap restriction to examine potential cumulative effects.
Abstract
Introduction
Physical activity (PA) and sleep contribute to overall health in early childhood. To explore the interactive relationships of these behaviors in older children and adults, ...previous studies have examined temporal between- and within-person associations through micro-longitudinal designs. However, such analyses have not been conducted in early childhood, when behaviors are guided by adult caregivers. The purpose of this analysis was to examine temporal and bidirectional associations between SED, PA, and sleep in preschool children.
Methods
Wake (activity counts/min and percent time in SED, light PA LPA, and moderate-to-vigorous PA MVPA) and overnight sleep (sleep duration, sleep efficiency SE, mid-sleep point MSP) were assessed via wrist-based actigraphy (mean = 10.4 days and 9.8 nights) and recorded as repeated (daily) measures. Multilevel models with lagged effects and AR(1) error covariance structure were used to examine the temporal associations between wake and sleep measures and adjusted for age, sex, socioeconomic status, and nap frequency.
Results
With PA measures as predictors, between-person associations were positive between activity counts and SE (p=0.004), SED and SE (p=0.004), LPA and sleep duration (p=0.005), and negative between LPA and MSP (p=0.039) and MVPA and SE (p=0.003). Within-person associations were positive between activity counts and sleep duration (p=0.010), activity counts and SE (p=0.018), MVPA and sleep duration (p=0.003), MVPA and SE (p=0.004), and negative between SED and SE (p=0.034) and LPA and sleep duration (p=0.045). With sleep measures as predictors, associations were positive between sleep duration and LPA (p<0.001) and SE and SED (p=0.008), and negative between MSP and LPA (p=0.009), SE and activity counts (p=0.001), and SE and MVPA (p=0.003). Within-person associations were positive between SE and activity counts (p=0.001) and SE and MVPA (p=0.001), and negative between sleep duration and LPA (p=0.001) and SE and SED (p=0.012).
Conclusion
Generally, days with higher levels of activity or sleep were not associated with greater subsequent sleep or PA. Conversely, when participants obtained greater PA or sleep compared to their individual average, some beneficial associations were evident. These findings demonstrate some evidence of temporal associations between PA and sleep, although the bidirectional nature was not conclusive.
Support (if any)
NIH R01 HL111695
Early childhood is an important age for brain and cognitive development. Given the support of physical activity and fitness on cognition and academic performance in older children, more research has ...emerged recently focusing on younger children. In this systematic review, the authors review the relations between physical activity/fitness and academic-related (ie, school readiness and cognitive) outcomes in early childhood.
A search was conducted from PubMed, PsycINFO, Web of Science, ERIC databases, and reference lists for articles that had participants aged less than 6 years were written in English, and were in peer-reviewed journals. Articles were excluded if the design was a case study or case series report. The Grading Recommendations Assessment, Development and Evaluation framework was followed to assess the quality of evidence by study design.
Sixty-eight articles reporting on 72 studies (29 observational and 43 experimental) were included. The majority of study effects were mixed, and the quality of evidence varied from very low to low.
A clear consensus about the role of physical activity and fitness on academic-related outcomes in early childhood is still lacking given the high heterogeneity in methodological approaches and overall effects. Additional high-quality studies are needed to determine what specific dosages of physical activity are impactful at this age.
We examined the comparability of children's nocturnal sleep estimates using accelerometry data, processed with and without a sleep log. In a secondary analysis, we evaluated factors associated with ...disagreement between processing approaches. Children (n = 722, age 5-12 years) wore a wrist-based accelerometer for 14 days during Autumn 2020, Spring 2021, and/or Summer 2021. Outcomes included sleep period, duration, wake after sleep onset (WASO), and timing (onset, midpoint, waketime). Parents completed surveys including children's nightly bed/wake time. Data were processed with parent-reported bed/wake time (sleep log), the Heuristic algorithm looking at Distribution of Change in Z-Angle (HDCZA) algorithm (no log), and an 8 p.m.-8 a.m. window (generic log) using the R-package 'GGIR' (version 2.6-4). Mean/absolute bias and limits of agreement were calculated and visualised with Bland-Altman plots. Associations between child, home, and survey characteristics and disagreement were examined with tobit regression. Just over half of nights demonstrated no difference in sleep period between sleep log and no log approaches. Among all nights, the sleep log approach produced longer sleep periods (9.3 min; absolute mean bias AMB = 28.0 min), shorter duration (1.4 min; AMB = 14.0 min), greater WASO (11.0 min; AMB = 15.4 min), and earlier onset (13.4 min; AMB = 17.4 min), midpoint (8.8 min; AMB = 15.3 min), and waketime (3.9 min; AMB = 14.8 min) than no log. Factors associated with discrepancies included smartphone ownership, bedroom screens, nontraditional parent work schedule, and completion on weekend/summer nights (range = 0.4-10.2 min). The generic log resulted in greater AMB among sleep outcomes. Small mean differences were observed between nights with and without a sleep log. Discrepancies existed on weekends, in summer, and for children with smartphones and screens in the bedroom.
The purpose of this micro-longitudinal study was to explore daily associations between daytime movement behaviors (sedentary time and physical activity) and nap sleep in young children. In 298 ...children (age = 51.0 ± 9.6 months, 43.6% female), wrist-based actigraphy (mean wear time = 10 days) assessed sedentary time, total physical activity, and provided an estimate of nap sleep duration and efficiency. Multilevel logistic and linear regression models were used to examine temporal within-person relations between wake behaviors and nap sleep, and adjusted for overnight sleep duration between days of interest, age, sex, and socioeconomic status. Movement behaviors were not related to the likelihood of next-day napping, but when children were less sedentary (OR = 0.96;
< 0.001) or more active (OR = 1.01;
= 0.001) in the morning, they were more likely to nap that same day. Movement behaviors were not associated with nap sleep duration or efficiency. Conversely, on days children napped, they were less sedentary (B = -2.09,
< 0.001) and more active (B = 25.8,
< 0.001) the following day. Though napping and movement behaviors had some reciprocal relations, effect sizes in the present study were small. Further studies should examine children with more diverse sleep health and from different childcare settings.
Unhealthy dietary choices are associated with poor sleep in children through adults. Yet, how diet and sleep are related in early childhood, when diet is reliant on parent choices around food ...availability, is unknown. The authors aimed to explore how frequency of fruit, vegetable, fast food, and soda consumption are associated with preschool children's sleep quality. They also considered how parenting factors may impact the relationship between children's sleep and diet. Actigraphy data were collected from 383 children 33-70 months old. Caregivers reported on child food and beverage frequency, demographics, and health items. Parenting strategies were assessed using the Parenting Scale. Multiple linear regression was used to examine associations between sleep and dietary measures with socioeconomic status, race-ethnicity, physical activity, and body mass index as covariates. Shorter nap duration was associated with more frequent consumption of fruits and vegetables (B = -3.6, p = .03). Shorter nighttime and 24-hr sleep durations were associated with more frequent consumption of fast food (B = -6.5, p = .01; B = -5.8, p = .01). Shorter nighttime sleep and later sleep onset were associated with more frequent soda consumption (B = -9.2, p = .01; B = 0.23, p = .001). Use of ineffective parenting strategies was negatively associated with fruit and vegetable consumption (r = -.29, p = .01) and positively associated with soda consumption (r = .25, p = .02) but was unrelated to sleep measures. Thus, ineffective parenting strategies may underlie child access to unhealthy foods, which, in turn, contributes to poor sleep. Encouraging healthier dietary habits and educating caregivers on how to reinforce such practices may lead to better sleep outcomes in early childhood.
Women with abnormal glucose tolerance during pregnancy are at risk for cardiovascular disease (CVD), with higher rates among Hispanics. However, studies on the impact of lifestyle interventions on ...postpartum CVD profiles are sparse.
This is a secondary analysis of a controlled trial among a subsample of Hispanic women with abnormal glucose tolerance participating in Estudió PARTO (Project Aiming to Reduce Type twO diabetes; mean age = 28.2 y, SD: 5.8) who were randomized to a culturally modified Lifestyle intervention (n = 45) or a comparison Health and Wellness intervention (n = 55). Primary endpoints were biomarkers of cardiovascular risk (lipids, C-reactive protein, fetuin-A, and albumin-to-creatinine ratio) and insulin resistance (fasting insulin, glucose, HbA1c, homeostasis model assessment, leptin, tumor necrosis factor-alpha, and adiponectin) measured at baseline (6-wk postpartum) and 6 and 12 months.
In intent-to-treat analyses, there were no significant differences in changes in biomarkers of CVD risk or insulin resistance over the postpartum year. In prespecified sensitivity analyses, women adherent with the Lifestyle Intervention had more favorable improvements in insulin (intervention effect = -4.87, SE: 1.93, P = .01) and HOMA-IR (intervention effect = -1.15, SE: 0.53, P = .03) compared with the Health and Wellness arm. In pooled analyses, regardless of intervention arm, women with higher postpartum sports/exercise had greater increase in HDL-cholesterol (intervention effect = 6.99, SE: 1.72, P = .0001).
In this randomized controlled trial among Hispanic women with abnormal glucose tolerance, we did not observe a significant effect on postpartum biomarkers of CVD risk or insulin resistance. Women adherent to the intervention had more favorable changes in insulin and HOMA-IR.
For a health behavior intervention to be sustainable within preschool centers, the intervention should be implemented by classroom teachers. Unfortunately, teachers are constrained by demands such as ...meeting early childhood education standards. Therefore, the purpose of this pilot study was to examine the feasibility and preliminary efficacy of integrating a health behavior intervention into early education learning standards on physical activity (PA), diet, and sleep (PADS) behavior of preschoolers.
Two preschool centers were randomized to either the PADS (children, n = 60) or the control (CON; children, n = 54) group. The PADS intervention consisted of PADS lesson plans and activities embedded into Massachusetts early learning standards and were implemented for 4 days per week for 12 weeks. The CON preschool participated in their usual curriculum. PA was assessed using accelerometers for 7 consecutive days at baseline, 6 weeks, and 12 weeks. Other outcome variables were assessed with parental surveys at baseline and 12 weeks.
Significant group by time interactions were observed for moderate to vigorous PA (percentage of time) during the preschool day (PADS: baseline = 10.6% (4.2%), 12 wk = 13.2% (2.3%); CON: baseline = 12.4% (3.9%), 12 wk = 11.2% (3.6%); P = .02).
This pilot study provides preliminary evidence that integrating health behaviors into learning standards is feasible and potentially an effective way for increasing preschoolers' PA levels.
Despite childcare providers’ substantial interaction with toddlers, very little is known about providers’ perception of toddlers’ physical activity (PA) and how to facilitate toddler PA. This ...qualitative study examines facilitators, barriers, and components of a PA intervention to improve toddlers’ PA within the childcare setting. Providers from three childcare centers completed Qualtrics survey and participated in focus group meetings. Semi-structured focus group meetings were recorded, transcribed, and systematically analyzed. Providers viewed PA as essential for toddlers’ health. Providers felt that toddlers’ classroom behavior, attention span, and basic needs should be considered when engaging toddlers in PA. Providers expressed that a PA intervention targeting toddlers should be non-structured, include music and motor skill-related activities, occur 2–3 days/week, and last 10–30 min. However, structured activities should last < 5 min. This study highlights our understanding of providers’ perceptions of PA, challenges they faced in getting toddlers to be active, and intervention components needed improving toddlers’ PA.