Changes in physical activity over time in young children: a longitudinal study using accelerometers

Profile of the PLAY spaces & environments for children's physical activity, sedentary behaviour and sleep (PLAYCE) cohort study, Western Australia

BACKGROUND

Childhood is a critical period for the development of movement behaviours such as physical activity, sleep and sedentary behaviour. The PLAYCE Cohort was established to investigate how movement behaviours change over early to middle childhood, across key behaviour settings and relationships with health and development. An overview of the PLAYCE cohort, summary of key findings to date, and future research opportunities are presented.

METHODS

Children were recruited at 2-5 years of age (preschool; Wave 1) via early childhood education and care (ECEC) services and were followed up in junior primary school (5-7 years; Wave 2) at 8-10 years (Wave 3) and again at 11-13 years (Wave 4; in progress). Children's movement behaviours were measured via parent-report and accelerometry. Social-emotional development, motor development, weight status, diet, and child and family socio-demographics were parent-reported. Physical environmental features of children's key behaviour settings (home, neighbourhood, ECEC and school) were collected using geo-spatial and audit data.

RESULTS TO DATE

At wave 1 (2-5 years), only 8% of children met all three recommendations of the Australian 24-hour Movement Guidelines for the Early Years. Meeting all recommendations (8%) was positively associated with boys social-emotional development. Physical environment features of the home yard (size, play equipment, natural features) were positively associated with preschool children's physical activity. Tree canopy and more portable play equipment in ECEC outdoor areas was also positively associated with children's outdoor time and physical activity.

CONCLUSIONS

Wave 4 (11-13 years) data collection will be completed in early 2026. Traditional longitudinal and compositional data analysis of the PLAYCE cohort will be undertaken. Four waves of data will provide detailed patterns of movement behaviours and their effect on child health and development as well as the environmental influences on children's movement behaviours across early to middle childhood. The findings can be used to inform national and international 24-Hour Movement Guidelines and behaviour setting-specific as well as population-level interventions to benefit child health and wellbeing across early to middle childhood.

Intra-articular injection of a cross-linked hyaluronic acid combined with triamcinolone hexacetonide improves pain at six months in patients with mild to moderate hip osteoarthritis: A prospective observational study

OBJECTIVES

Joint-preserving interventions, such as intra-articular viscosupplementation injections, are evolving and requiring efficacy and safety evaluations through an evidence-based approach. The objective of this study was to assess the use of a hyaluronic acid and corticosteroid-based injection (Cingal™; Anika Therapeutics, Bedford, MA, USA) in improving pain and functional outcomes for patients aged between 40 and 65 with mild to moderate hip osteoarthritis (OA) six months post-injection.

METHODS

This prospective observational study included 100 patients receiving a single ultrasound-guided intra-articular injection of Cingal™. Eligible patients seen in participating orthopaedic, physiatry and sports medicine clinics were evaluated at baseline, one-month, and six-month follow-up. The primary outcome was patient-reported hip pain (Visual Analogue Scale, VAS) at six months post-injection. Secondary outcomes included hip function (Hip Disability and Osteoarthritis Outcome Score, HOOS), quality of life (Short-Form 12, SF-12), pain medication use, range of motion (ROM), physical activity (activity tracker), and adverse events.

RESULTS

Ninety-six patients received the injection; 91 had complete data for primary outcome analysis. Statistically significant improvements were observed in VAS (p ​< ​0.001), HOOS (p ​< ​0.001), and SF-12 scores (Physical Component Summary, p ​= ​0.005; Mental Component Summary, p ​= ​0.022) from baseline to six months post-injection. Pain medication use decreased from 50.0% to 34.0% (p ​= ​0.035). No statistically significant change was observed in ROM or activity level. Adverse events were reported in 9.5% of patients: five (5.3%) experienced hip pain for less than seven days, one for more than seven days but less than one month, and three (3.2%) underwent hip arthroplasty.

CONCLUSION

Patients receiving an ultrasound-guided Cingal™ injection for hip OA reported statistically significantly reduced hip pain, improved function and quality of life, and reduced pain medication use at six months. The most common adverse event was transient hip pain.

LEVEL OF EVIDENCE

Prospective observational study, Level III.

Daily Physical Activity, Sports Participation, and Executive Function in Children

Importance

It is unclear whether daily physical activity and sports participation relate to executive function (EF) in children.

Objective

To explore associations between early-life physical activity, sports participation, and executive function in primary school children.

Design, Setting, and Participants

Data for this cohort study were collected from April 2006 to December 2017 from the Groningen Expert Center for Kids with Obesity (GECKO) Drenthe birth cohort, which includes Northern Dutch children. Preschool children aged 5 to 6 years and primary school children aged 10 to 11 years with valid EF, daily physical activity, and sports participation data were included in the analysis. Data were analyzed from May 2023 to February 2024.

Exposures

At ages 5 to 6 years, daily physical activity was measured with accelerometry. At ages 10 to 11 years, sports participation data were collected using the Short Questionnaire to Assess Health-Enhancing Physical Activity.

Main Outcomes and Measures

Executive function was assessed using the Behavior Rating Inventory of Executive Function at ages 10 to 11 years.

Results

A total of 880 children (470 female [53.4%]; mean [SD] age at EF measurement, 11.1 [0.4] years) were included. Moderate to vigorous physical activity at ages 5 to 6 years did not correlate with EF at ages 10 to 11 years (eg, Global Executive Composite [GEC]: β, 0.16; 95% CI, -0.21 to 0.53). Higher levels of light physical activity at ages 5 to 6 years were associated with poorer inhibitory control (β, 0.86; 95% CI, 0.24-1.47) and self-monitoring (β, 0.79; 95% CI, 0.09-1.48) at ages 10 to 11 years, while greater sedentary time was associated with better inhibitory control (β, -0.62; 95% CI, -1.08 to -0.16) and self-monitoring (β, -0.57; 95% CI, -1.09 to -0.06). Compared with children engaged in individual sports, team sports participants exhibited better overall EF (mean difference [SE], -3.03 [0.81]), behavior regulation (mean difference [SE], -3.39 [0.77]), and metacognition (mean difference [SE], -2.55 [0.81]). Children involved in both types of sports vs only individual sports had better EF (GEC: mean difference [SE], -2.66 [0.93]).

Conclusions and Relevance

In this cohort study of Dutch children, early-life moderate to vigorous physical activity was not associated with EF in middle childhood. Children participating in team sports at ages 10 to 11 years consistently exhibited superior EF compared with participants in individual sports.

Identifying data gaps in early childhood physical activity evidence

Childhood physical activity sets the foundation for health. While we know many factors that contribute to physical activity, there are limitations in our knowledge, especially in early childhood. Through our review, we identify gaps in existing datasets to guide future research.

Early Childhood Education and Care Attendance and Its Association With Outdoor Play, Screen Time and Sleep Duration of Young Children: Findings From the CHAT Trial in Australia

BACKGROUND

Effects of attending early childhood education and care (ECEC) on health behaviours of young children remain unclear. This study aimed to investigate whether ECEC attendance was associated with outdoor play, screen time, sleep duration and family demographics of children aged 2 and 3 years.

METHODS

Secondary analysis was conducted using data extracted from two linked trials conducted in Australia, 2017-2020. Telephone surveys were conducted with participating mothers for data collection. Multiple logistic and linear regression models were built to investigate the associations of ECEC attendance with outdoor play, screen time, sleep duration and family demographics among young children.

RESULTS

At ages 2 and 3 years, 797 and 537 mothers completed surveys, respectively. Of respondents, 65% and 72% of children attended ECEC, respectively. Children who attended ECEC had 17 min (95% CI 3.8-30.5) and 28 min (95% CI 14.1-41.9) more daily outdoor playtime and had 13 min (95% CI 4.0-21.5) and 19 min (95% CI 6.4-30.7) less daily screen time at home at 2 and 3 years, respectively. Although ECEC attendance was not associated with sleep duration, children who attended ECEC were more likely to meet all three recommendations (outdoor play, screen time and sleep) with adjusted odds ratio (AOR) 1.84 (95% CI 1.24-2.72) at age 2 and AOR 2.34 (95% CI 1.28-4.28) at age 3. Mothers who were employed, first-time mothers, spoke English at home or had a high household income were more likely to use ECEC services.

CONCLUSIONS

ECEC services may hold promise to influence outdoor play and screen time among young children. Children from lower socio-demographic background had a lower rate of ECEC attendance. Future health promotion programmes for young children need to also consider children who do not attend ECEC.

Data Analytics in Physical Activity Studies With Accelerometers: Scoping Review

BACKGROUND

Monitoring free-living physical activity (PA) through wearable devices enables the real-time assessment of activity features associated with health outcomes and provision of treatment recommendations and adjustments. The conclusions of studies on PA and health depend crucially on reliable statistical analyses of digital data. Data analytics, however, are challenging due to the various metrics adopted for measuring PA, different aims of studies, and complex temporal variations within variables. The application, interpretation, and appropriateness of these analytical tools have yet to be summarized.

OBJECTIVE

This research aimed to review studies that used analytical methods for analyzing PA monitored by accelerometers. Specifically, this review addressed three questions: (1) What metrics are used to describe an individual's free-living daily PA? (2) What are the current analytical tools for analyzing PA data, particularly under the aims of classification, association with health outcomes, and prediction of health events? and (3) What challenges exist in the analyses, and what recommendations for future research are suggested regarding the use of statistical methods in various research tasks?

METHODS

This scoping review was conducted following an existing framework to map research studies by exploring the information about PA. Three databases, PubMed, IEEE Xplore, and the ACM Digital Library, were searched in February 2024 to identify related publications. Eligible articles were classification, association, or prediction studies involving human PA monitored through wearable accelerometers.

RESULTS

After screening 1312 articles, 428 (32.62%) eligible studies were identified and categorized into at least 1 of the following 3 thematic categories: classification (75/428, 17.5%), association (342/428, 79.9%), and prediction (32/428, 7.5%). Most articles (414/428, 96.7%) derived PA variables from 3D acceleration, rather than 1D acceleration. All eligible articles (428/428, 100%) considered PA metrics represented in the time domain, while a small fraction (16/428, 3.7%) also considered PA metrics in the frequency domain. The number of studies evaluating the influence of PA on health conditions has increased greatly. Among the studies in our review, regression-type models were the most prevalent (373/428, 87.1%). The machine learning approach for classification research is also gaining popularity (32/75, 43%). In addition to summary statistics of PA, several recent studies used tools to incorporate PA trajectories and account for temporal patterns, including longitudinal data analysis with repeated PA measurements and functional data analysis with PA as a continuum for time-varying association (68/428, 15.9%).

CONCLUSIONS

Summary metrics can quickly provide descriptions of the strength, frequency, and duration of individuals' overall PA. When the distribution and profile of PA need to be evaluated or detected, considering PA metrics as longitudinal or functional data can provide detailed information and improve the understanding of the role PA plays in health. Depending on the research goal, appropriate analytical tools can ensure the reliability of the scientific findings.

Developmental trends in young children's device-measured physical activity and sedentary behaviour

BACKGROUND

Knowledge of developmental trends in meeting age-specific 24-hour movement behaviour guidelines is lacking. This study describes developmental trends in device-measured physical activity and sedentary time over a three-year period among Western Australian children aged two to seven years, including differences between boys and girls. The proportion of children meeting age-specific physical activity guidelines before and after they transition to full-time school was also examined.

METHODS

Data from waves 1 and 2 of the Play Spaces and Environments for Children's Physical Activity (PLAYCE) cohort study were used (analysis n = 1217). Physical activity and sedentary time were measured by accelerometry at ages two to five (preschool, wave 1) and ages five to seven (commenced full-time school, wave 2). Accelerometer data were processed using a validated machine-learning physical activity classification model. Daily time spent in sedentary behaviour, energetic play (moderate-to-vigorous physical activity (MVPA)), total physical activity, and meeting physical activity guidelines were analysed using linear and generalised linear mixed-effects models with age by sex interaction terms.

RESULTS

All movement behaviours changed significantly with increasing age, and trends were similar in boys and girls. Total daily physical activity increased from age two to five then declined to age seven. Mean daily total physical activity exceeded 180 min/day from ages two to five. Daily energetic play increased significantly from age two to seven, however, was below 60 min/day at all ages except for seven-year-old boys. Daily sedentary time decreased to age five then increased to age seven but remained lower than at age two. All two-year-olds met their age-specific physical activity guideline, decreasing to 5% of girls and 6% of boys at age four. At age seven, 46% of boys and 35% of girls met their age-specific physical activity guideline.

CONCLUSIONS

Young children's energetic play and total physical activity increased with age, but few children aged three to seven met the energetic play (MVPA) guideline. Interventions should focus on increasing children's energetic play in early childhood. Clearer guidance and strategies are needed to support young children as they change developmentally and as they transition from one age-specific movement guideline to the next.

Movement behaviour education for parents in prenatal, postnatal, and pediatric care in Canada: A needs assessment

BACKGROUND

Parents/guardians can greatly influence their child's movement behaviours (i.e., physical activity, sedentary behaviour, and sleep). Yet, they have reported to lack sufficient background knowledge to foster healthy movement habits, and little is known about specific educational gaps. The aim of this study was to explore the educational background and needs regarding promoting healthy movement behaviours in early childhood among parents/guardians living in Canada.

METHODS

A cross-sectional study was conducted with parents/guardians living in Canada who had at least one child under the age of 5 years. Participants completed an online survey capturing their demographics, information they received about movement behaviours in early childhood during their prenatal/postnatal care or child's pediatrician appointments, where they sourced information about these topics, content areas they would like more information on, and preferred format for delivery. Descriptive statistics and frequencies were calculated for all outcome variables and logistic regression was used to explore if sociodemographic variables were associated with receiving movement behaviour-related education across care types.

RESULTS

Among the 576 parents/guardians who completed the survey, many reported no mention of any movement behaviour in their prenatal (49.4%), postnatal (29.6%), and pediatric care (37.2%). Physical activity was the most cited movement behaviour across care types, with 42.4%, 57.9%, and 54.8% of participants indicating this was discussed in their prenatal, postnatal, and pediatric care, respectively. Only 41.7% of parents/guardians reported asking their child's pediatrician about movement behaviours, while most relied on social media (70.9%), internet websites/news articles (68.7%), and family/friends (67.6%). The most sought-after movement behaviour topics included incorporating movement into traditionally sedentary activities (68.8%) and activity ideas to break up sitting time (65.0%), and participants expressed preference to receive more information via social media (63.2%), an online resource package (47.8%), or email (46.6%).

CONCLUSIONS

Given the noted inconsistencies in education relating to movement behaviours in maternal and pediatric care, this study highlights the opportunity for greater integration of this type of education across care types. Ensuring all parents/guardians receive evidence-based and consistent guidance on their child's movement behaviours will help ensure young children receive the best start to a healthy active life.

The Influence of Perceptions of Competence on Motor Skills and Physical Activity in Middle Childhood: A Test of Mediation

The mediating effect of perceptions of physical competence (PPC) on the relationship between motor competence and physical activity levels is documented in adolescence. However, it is unclear at what age this begins. In this study, we examined whether PPC mediated the relationship between moderate-vigorous physical activity (MVPA) or sedentary behaviour and motor competence in middle childhood. The participants were 129 children (mean age = 8.3 years) from eight elementary schools. MVPA and sedentary behaviour were measured using Actigraph accelerometers, and motor competence was assessed using the Test of Gross Motor Development, Second Edition. The Pictorial Scale of Perceived Competence and Social Acceptance for Young Children and The Self-Perception Profile for Children were used to assess PPC. In this study, PPC did not predict either MVPA or engagement in sedentary behaviours. Further, structural equation modelling revealed that PPC did not mediate the relationship between motor competence and MVPA or between motor competence and sedentary behaviour. These results suggest that at 8 years of age, children's perceptions do not influence their participation in physical activities. It is possible that factors influencing PPC, such as peer comparisons and performance outcomes, have more impact in later childhood or adolescence. In turn, those perceptions may affect children's or adolescents' choices to opt in or out of physical activities.

Changes in Pediatric Movement Behaviors During the COVID-19 Pandemic by Stages of Lockdown in Ontario, Canada: A Longitudinal Cohort Study

BACKGROUND

Children's movement behaviors have been affected by the COVID-19 pandemic; however, little is known regarding movement behavior patterns over time by government-issued lockdowns. Our primary objective was to evaluate how children's movement behaviors changed by stages of lockdown/reopening in Ontario, Canada, from 2020 to 2021.

METHODS

A longitudinal cohort study with repeated measures of exposure and outcomes was conducted. The exposure variables were dates from before and during COVID-19 when child movement behavior questionnaires were completed. Lockdown/reopening dates were included as knot locations in the spline model. The outcomes were daily screen, physical activity, outdoor, and sleep time.

RESULTS

A total of 589 children with 4805 observations were included (53.1% boys, 5.9 [2.6] y). On average, screen time increased during the first and second lockdowns and decreased during the second reopening. Physical activity and outdoor time increased during the first lockdown, decreased during the first reopening, and increased during the second reopening. Younger children (<5 y) had greater increases in screen time and lower increases in physical activity and outdoor time than older children (≥5 y).

CONCLUSIONS

Policy makers should consider the impact of lockdowns on child movement behaviors, especially in younger children.

Accelerometer-Measured Physical Activity and Sedentary Time among Children in Japan before and during COVID-19: A Cross-Sectional and Longitudinal Analysis

This study examined changes in physical activity (PA), sedentary behavior (SB), screen time, sleep, and executive function among Japanese preschoolers between COVID-19 pre-pandemic and pandemic periods, using cross-sectional and longitudinal data. Accelerometer data from 63 children aged 5-6 years were collected from three kindergartens in Tokyo, Japan, in late 2019 (pre-COVID-19). This was compared to the data of 49 children aged 5-6 years from the same kindergartens, collected in late 2020 (during COVID-19). Sixteen children in the pre-COVID-19 cohort also participated in the 2020 survey and provided data for the longitudinal analysis. The mean minutes of PA, SB, screen time, and sleep duration, as well as executive function, were compared between the pre- and during COVID-19 cohorts. After adjusting for school, sex, and accelerometer wear time, there were no significant differences in any of the measured outcomes between the two cohorts. However, the analysis of longitudinal data revealed significant increases in time spent in SB and on screens, and a decrease in light-intensity PA and sleep duration during the pandemic compared to the pre-pandemic period. Results suggest that, despite the COVID-19 pandemic, young children's activity levels and SB did not significantly differ from pre-pandemic levels. However, school-aged children's SB, light PA, and sleep time were affected, although this cannot be disentangled from the effects of the transition to school.

Youth physical activity and the COVID-19 pandemic: A systematic review

•

Numerous studies examined youth physical activity (PA) during the COVID-19 pandemic.

•

Overall decreases in youth PA were seen during the first 1.5 years of the pandemic.

•

There were differences in PA by sub-populations (e.g., age, sex/gender)

•

There were also differences in PA by location/type (e.g., outdoor, play)

•

Programming and policy should focus on evolving PA promotion for youth.

The purpose of the systematic review was to identify, evaluate, and synthesize evidence from available published literature examining the impact of the coronavirus disease 2019 (COVID-19) pandemic on youth physical activity (PA). A systematic review of the literature was conducted for years 2020–2021. Published articles were searched in eight databases. Inclusion criteria included: availability of full-text, written in English language, and reported quantitative or qualitative results of original or secondary data on PA and COVID-19 related factors among youth (ages 5–17 years). A standard quality assessment tool assessed risk of bias and quality of included articles. The search retrieved 2,899 articles with 51 articles ultimately meeting inclusion criteria. The majority of articles (65 %) investigated change in PA from before to during the pandemic. Most evidence indicated an overall decrease in youth PA levels during the pandemic with differences observed among sub-populations (e.g., age, sex or gender), type, and location. Findings suggest pandemic-related closures hindered PA participation due to a high reliance on school- and sport-based PA. Programmatic strategies (e.g., activity breaks, active curriculum, free online activities/lessons) should include aligning intervention measures and geared towards evolving and ongoing PA promotion based on the latest findings.

Day-level associations of physical activity and sedentary time in mother-child dyads across three years: a multi-wave longitudinal study using accelerometers

Understanding associations between mothers' and children's physical activity and sedentary behavior on more fine-grained timescales can provide insights into real-time intervention opportunities. This study examined the extent to which mothers' and their children's device-measured moderate-to-vigorous physical activity (MVPA) and sedentary time (SDT) were associated at the day level during non-school time. Mother-child dyads (N = 193; baseline Mean ages = 40.69 ± 6.11 [mother] and 9.57 ± 0.89 [child] years) provided 3,135 paired days of accelerometry data from six bi-annual waves across three years. Controlling for covariates, multilevel models revealed that mothers' and their children's MVPA and SDT were positively associated at the day level during non-school time, both on weekdays and weekends. During weekdays, the day-level association for SDT was stronger for older than younger children, and the day-level association for MVPA was stronger for boys than girls. Designing family-based interventions targeting school-age children and their mothers during non-school time across the week may be useful for promoting active lifestyles.

Trajectories of physical activity and sedentary time in Norwegian children aged 3-9 years: a 5-year longitudinal study

BACKGROUND

Limited evidence exists regarding the longitudinal development of physical activity during early to mid childhood. The aim of this study was to determine physical activity and sedentary time trajectories in children aged 3‒9 years from Western Norway.

METHODS

A sample of 294 children (51% boys; aged 3‒5 years at baseline) from the Sogn og Fjordane Preschool Physical Activity Study was followed annually over 5 years (2015‒2019). Physical activity was measured every autumn during this period using hip-based accelerometry (ActiGraph GT3X+). Data was processed as counts. We used linear mixed models to analyse the data. Primary analyses included trajectories for total and intensity-specific physical activity (light, moderate, vigorous, and moderate to vigorous intensity) and sedentary time for boys and girls using 1-s epoch. Secondary analyses included trajectories for weekdays versus weekend days, preschool/school hours versus after school hours, and 1- versus 60-s epoch lengths.

RESULTS

Over the total day, significant associations with age were found for boys and girls for all physical activity intensities and sedentary time (p < .001). Total physical activity peaked at age 5, whereas intensity-specific physical activity levels peaked at age 3 to 8 years (light intensity: 3-4 years; moderate intensity: 4-7 years; vigorous intensity: 7-8 years; moderate to vigorous intensity: 5-8 years). Boys had higher physical activity levels and more favourable trajectories than girls. Sedentary time increased from ages 3 to 9. Changes over time were larger for weekdays than for weekend days and larger for preschool/school hours than for after school hours. The use of a 60-s epoch resulted in larger changes over time than a 1-s epoch.

CONCLUSIONS

Our findings suggest physical activity levels peaked between the ages of 3 and 8 years. Finding ways to prevent decline in physical activity during the transition from preschool to primary school is important, especially for girls. Standardising epoch length will help when comparing physical activity and sedentary behaviour across studies.

Promoting glycemic control in young children with type I diabetes: Results from a pilot intervention for parents

OBJECTIVE

Nutrition and physical activity are key components of daily diabetes care in young children with type I diabetes (T1D). Normative developmental behavioral challenges related to nutrition and physical activity complicate management of T1D. The current pilot study evaluated the feasibility, acceptability, and indications of behavior change of an intervention aimed at improving nutrition and physical activity in young children with T1D.

METHOD

Thirty-6 parents of young children (ages 2-5 years, M = 4.2) with T1D from 2 clinics in the Washington, DC area were randomized to receive the type One Training (TOTs) program or Usual Care (UC). Assessments included recruitment and completion rates, participant acceptability, and outcomes including glycemic variability via continuous glucose monitoring, nutritional intake via remote food photography, physical activity via accelerometers, and parental report on behavior and psychosocial functioning.

RESULTS

Despite recruitment challenges, the TOTs program was feasible to administer, with high program and assessment completion rates. Acceptability ratings were very high but differed by recruitment site. Participants randomized to TOTs had an increase in percent of time in target glycemic range and reduction in behavioral feeding problems between baseline and follow-up while those randomized to UC did not. Participants in UC demonstrated a decrease in in moderate to vigorous physical activity at follow-up.

CONCLUSIONS

The TOTs program demonstrated preliminary feasibility and acceptability. Future research will examine components of treatment for evidence of efficacy and target the intervention to those most likely to benefit. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Training Pre-Service Early Childhood Educators in Physical Activity (TEACH): Protocol for a Quasi-Experimental Study

Background: Early childhood educators (ECEs) influence young children’s early uptake of positive health behaviours in childcare settings and serve as important daytime role models. As such, it is imperative that post-secondary early childhood education programs provide students with the foundational knowledge and professional training required to confidently facilitate quality active play opportunities for young children. The primary objective of the Training pre-service EArly CHildhood educators in physical activity (TEACH) study is to develop and implement an e-Learning course in physical activity and sedentary behaviour to facilitate improvements in: pre-service ECEs’ self-efficacy and knowledge to lead physical activity and outdoor play opportunities and minimize sedentary behaviours in childcare. This study will also explore pre-service ECEs’ behavioural intention and perceived control to promote physical activity and outdoor play, and minimize sedentary behaviour in childcare, and the implementation of the e-Learning course. Methods/Design: A mixed-methods quasi-experimental design with three data collection time points (baseline, post-course completion, 3-month follow-up) will be employed to test the e-Learning course in early childhood education programs (n = 18; 9 experimental, 9 comparison) across Canada. Pre-service ECEs enrolled in colleges/universities assigned to the experimental group will be required to complete a 4-module e-Learning course, while programs in the comparison group will maintain their typical curriculum. Pre-service ECEs’ self-efficacy, knowledge, as well as behavioural intention and perceived behavioural control will be assessed via online surveys and module completion rates will be documented using website metrics. Group differences across timepoints will be assessed using linear mixed effects modelling and common themes will be identified through thematic analysis. Discussion: The TEACH study represents a novel, evidence-informed approach to address the existing gap in physical activity and sedentary behaviour-related education in Canadian post-secondary early childhood education programs. Moreover, e-Learning platforms, can be employed as an innovative, standardized, and scalable way to provide ECEs with consistent training across jurisdictions.

Preschool to School-Age Physical Activity Trajectories and School-Age Physical Literacy: A Longitudinal Analysis

PURPOSE

The associations between longitudinal physical activity (PA) patterns across childhood and physical literacy have not been studied. The purpose of this study was to identify PA trajectories from preschool to school-age, and to determine if trajectory group membership was associated with school-age physical literacy.

METHODS

Participants (n = 279, 4.5 [0.9] y old, 48% girls) enrolled in this study and completed annual assessments of PA with accelerometry over 6 timepoints. Physical literacy was assessed at timepoint 6 (10.8 [1.0] y old). Group-based trajectory analysis was applied to identify trajectories of total volume of PA and of moderate to vigorous PA and to estimate group differences in physical literacy.

RESULTS

Three trajectories of total volume of PA and of moderate to vigorous PA were identified. Groups 1 (lowest PA) included 40% to 53% of the sample, groups 2 included 39% to 44% of the sample, and groups 3 (highest PA) included 8% to 16% of the sample. All trajectories declined from timepoint 1 to timepoint 6. School-age physical literacy was lowest in trajectory groups with the lowest total volume of PA or moderate to vigorous PA over time (P < .05).

CONCLUSIONS

PA should be promoted across early and middle childhood, as it may play a formative role in the development of school-age physical literacy.

Longitudinal differences in levels and bouts of sedentary time by different day types among Australian toddlers and pre-schoolers

The aim of the present study was to characterize sedentary time (ST) and sedentary bouts among young children, across a typical week and by day type (childcare days, non-childcare days and weekends), over a 12-month period.ST % (ST/accelerometer wear time*100) and number of sedentary bouts/hours were assessed using accelerometers at two time-points 12-months apart in 153 toddlers and 74 pre-schoolers. Differences between baseline and follow-up according to the whole week and the different day types were calculated using linear mixed models with adjustment for age, sex, socio-economic status and zBMI.During the weekend, toddlers had more 20-30 min/h sedentary bouts at follow-up than at baseline (MD: 0.03). In pre-schoolers, ST % (MD:-8.4), the number of 1-4 min/h (MD:-1.45), 5-9 min/h (MD: -0.46) and 10-19 min/h sedentary bouts (MD:-0.11) were lower at baseline, compared to follow-up, on non-childcare days; as were the number of 5-9 min/h sedentary bouts on weekends (MD:0.40). P < 0.05 for all.This study found that longer sedentary bouts (20-30 min/h) tended to decrease among toddlers and pre-schoolers, whereas ST and shorter sedentary bouts increased over 12-months, particularly among pre-schoolers on non-childcare weekdays. Non-childcare days, and home environment may be targeted for intervention to reduce ST and sedentary bouts among pre-schoolers.

A Longitudinal Analysis Examining the Associations of Tummy Time With Active Playtime, Screen Time, and Sleep Time

BACKGROUND

Evidence links tummy time (ie, the time spent in awake prone positioning that is encouraged and supervised by an adult) to infants' health outcomes such as gross motor and total development. However, the associations between tummy time and other movement and sleep behaviors as the child develops remain unknown. The aim of this study was to examine whether early introduction and practice of tummy time within the first 6 months of age were associated with active and outdoor playtime, screen time, and nocturnal sleep time of children when they were 12 and 24 months old.

METHODS

A longitudinal analysis was conducted using data extracted from an Australian trial. Using telephone surveys with mothers, demographic data were collected from third trimester of pregnancy and tummy time data were collected at 6 months of age. Data on playtime, screen time, and nocturnal sleep duration as dependent variables were collected at 12 and 24 months of age. Multiple logistic regression models were built to investigate the associations.

RESULTS

Children who started tummy time within 4 weeks of age were more likely to have >10 hours sleep at night at 12 months (adjusted odds ratio 1.54, 95% confidence interval, 1.08-2.19). They were more likely to have >3 hours per day of outdoor play and have <1 hour per day of screen time at 24 months. Children who practiced tummy time every day were more likely to have >2 hours per day of active play at 12 months and have <1 hour per day of screen time at 24 months.

CONCLUSIONS

Starting tummy time earlier and frequently was associated with more favorable movement and sleep of young children at 12 and 24 months of age.

A framework for handling missing accelerometer outcome data in trials

Accelerometers and other wearable devices are increasingly being used in clinical trials to provide an objective measure of the impact of an intervention on physical activity. Missing data are ubiquitous in this setting, typically for one of two reasons: patients may not wear the device as per protocol, and/or the device may fail to collect data (e.g. flat battery, water damage). However, it is not always possible to distinguish whether the participant stopped wearing the device, or if the participant is wearing the device but staying still. Further, a lack of consensus in the literature on how to aggregate the data before analysis (hourly, daily, weekly) leads to a lack of consensus in how to define a "missing" outcome. Different trials have adopted different definitions (ranging from having insufficient step counts in a day, through to missing a certain number of days in a week). We propose an analysis framework that uses wear time to define missingness on the epoch and day level, and propose a multiple imputation approach, at the day level, which treats partially observed daily step counts as right censored. This flexible approach allows the inclusion of auxiliary variables, and is consistent with almost all the primary analysis models described in the literature, and readily allows sensitivity analysis (to the missing at random assumption) to be performed. Having presented our framework, we illustrate its application to the analysis of the 2019 MOVE-IT trial of motivational interviewing to increase exercise.

The Relationship Between Physical Activity and School Success Among Children With and Without Special Health Care Needs

BACKGROUND

School-environments are thought to be strong influences of behavioral choices. There is limited research available on the role of physical activity (PA) and school success among children with special health care needs (CSHCN). The purpose of this study was to explore differences in PA among CSHCN and non-CSHCN and how the school success index is related to PA in both groups.

METHODS

Data were taken from new version of the National Survey of Children's Health (NSCH), which consolidated questions from the previous NSCH and the National Survey of Children with Special Health Care Needs (NS-CSHCN). Chi-square and logistic regression analyses were employed to examine group differences.

RESULTS

There were significant differences among both subgroups, although most school-aged children did not meet recommended PA guidelines. Chi-squared analyses indicated; school engagement and the parent's perception of child safety at school were associated with the likelihood of meeting PA guidelines. Logistic regression analyses showed that the odds of meeting PA guidelines were associated with the school success index.

CONCLUSIONS

Comprehensive school health programs should focus on PA both subgroups. School health educators should continue to advocate for safe and structured extracurricular activities to improve the child and adolescent's engagement and overall well-being.

Volume and accumulation patterns of physical activity and sedentary time: longitudinal changes and tracking from early to late childhood

BACKGROUND

Physical activity (PA) decreases and sedentary time (SED) increases across childhood, with both behaviours tracking. However, no studies have examined how accumulation patterns of PA and SED (i.e., prolonged bouts, frequency of breaks in sedentary time) change and track over time. The aim of this study was to investigate longitudinal changes in and tracking of total volume and accumulation patterns of SED, light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA) among boys and girls.

METHODS

In 2008/09 (T1), children in HAPPY (3-5y; n = 758) in Melbourne, Australia wore ActiGraph GT1M accelerometers to objectively assess SED, LPA, MPA and VPA. This was repeated at age 6-8y (T2; n = 473) and 9-11y (T3; n = 478). Ten pattern variables were computed: bouts of ≥ 5-, ≥ 10-, ≥ 15- and ≥ 20-min for SED, ≥ 1- and ≥ 5-min for LPA, ≥ 1-min for MPA, ≥ 1- and ≥ 5-min for VPA, and breaks in SED (interruptions of > 25 counts 15 s^- 1). Longitudinal mixed models examined changes from T1-3, controlling for T1 age. Generalized estimating equations assessed tracking over the three time points, controlling for T1 age and time between measurements. Analyses were stratified by sex.

RESULTS

Total volume and bouts of SED and SED breaks increased, while total volume and bouts of LPA decreased for both sexes. There was a small decrease in total volume of MPA for girls, but time spent in ≥ 1-min bouts increased for both sexes. Total volume of VPA increased for both sexes, with time spent in ≥ 1-min bouts increasing for boys only. All volume and pattern variables tracked moderately for boys, except for all SED bouts ≥ 15-min, LPA bouts ≥ 5-min and MPA bouts ≥ 1-min (which tracked weakly). For girls, total SED and SED bouts ≥ 1-min tracked strongly, total volume of LPA, MPA and VPA, ≥ 5- and ≥ 10-min SED bouts, and ≥ 1-min LPA and MPA bouts tracked moderately, and SED breaks, all SED bouts ≥ 15 min, LPA bouts ≥ 5 min and all VPA bouts tracked weakly.

CONCLUSIONS

Patterns of SED and PA change from early to late childhood; with the exception of SED breaks and VPA, changes were detrimental. Total volumes and short bouts tended to track more strongly than longer bouts. Interventions to prevent declines in PA and increases in SED are important from early in life.

Resemblance in accelerometer-assessed physical activity in families with children: the Lolland-Falster Health Study

Background

Evidence of intra-family resemblance in physical activity (PA) is lacking. The association between parent and child PA appears weak, the influence of age and gender on this association is uncertain, and no studies have investigated the degree of resemblance in family members’ PA behaviours such as walking, sitting/lying, and biking. Thus, the aims of the study were to examine the degree of resemblance in PA within families, specifically between parents and children, and to explore the size of resemblance across age of children, gender of parents and children, and intensity and type of PA.

Method

The study is a cross-sectional analysis of a subsample (902 parents and 935 children nested within 605 families) of the Danish population study Lolland-Falster Health Study. PA was measured using a dual-accelerometer system (Axivity AX3) with subsequent processing of time spent in light PA (LPA), moderate-to-vigorous PA (MVPA), and vigorous PA and classification of PA behaviour types. Families with at least one son/daughter aged 0–22 years and one parent providing minimum 4 days of valid accelerometer data were included in the analysis. A linear mixed model regression analysis was used to determine the intraclass correlation coefficient (ICC) of clustering among family members for PA intensities and PA behaviours, adjusted for sex, age, parental education, and the interaction between sex and age.

Results

In the analysis of within-family variation in PA, the ICCs across PA intensities and PA behaviours ranged from 0.06 to 0.34. We found stronger clustering in family members’ PA for LPA and behaviours requiring low energy expenditure (LPA: ICC 0.22 (95% confidence interval (CI) 0.17; 0.28), sitting/lying: ICC 0.34 (95% CI 0.28; 0.40)), and walking: ICC 0.24 (95% CI 0.19; 0.30) than for higher intensities (e.g. MVPA: ICC 0.07 (95% CI 0.03; 0.14)). The ICC for biking was 0.23 (95% CI 0.18; 0.29). Analyses on parent-child dyads gave similar results. No interaction effects for gender and age (except for biking) were found.

Conclusion

Parents and children’s time spent in PA behaviours requiring low energy expenditure had moderate resemblance within families, whereas engagement in PA with higher intensities showed small or close-to-zero resemblance.

Changes in Physical Fitness Among Preschool Children From Kraków (Poland) From 2008 to 2018

BACKGROUND

The aim of this study was to analyze the secular changes of the physical fitness of preschool children from Kraków, Poland between 2008 and 2018.

METHODS

The study group consisted of 2143 children (3- to 7-y-olds; 2008 cohort included 1037 children and the 2018 cohort included 1106 children). The following physical fitness tests were carried out: overhead medicine ball throw, standing broad jump, sit-and-reach test, and handgrip strength. Statistical differences between the cohorts were obtained using 2-way analysis of variance and Tukey tests.

RESULTS

Negative changes were noted for the standing broad jump and its relative results among boys. A negative trend was also observed for flexibility and ball throw. Positive changes were noted for the standing broad jump among girls, as well as the absolute and normalized results of handgrip strength in both sexes. Besides the flexibility, observed discrepancies were practically significant between the age groups. Differences between the cohorts reached practical significance in the case of absolute and normalized handgrip strength.

CONCLUSIONS

There was at least partial progress in the children's fitness. Physical fitness, in turn, is one of the most important health markers. Moreover, its low level is a predictor of diseases, including metabolic and cardiovascular ones, lower academic performance, and psychosocial problems.

"I Wasn't Sure What It Meant to be Honest"-Formative Research towards a Physical Literacy Intervention for Preschoolers

Physical literacy (PL) as a concept is important in developing lifelong physical activity; however, there is little research exploring how PL can be developed during the preschool years. This two-phase qualitative study sought the insights of academics/expert practitioners and preschool staff towards PL in order to inform the design of future preschool PL interventions. Phase One comprised of nine semi-structured interviews with experts in the field of children's physical activity and/or PL. Interview topics included perspectives on the concept of PL and recommendations for interventions targeted at improving preschool PL. Phase Two consisted of focus groups with practitioners from four local children's centres. Focus groups explored perspectives on the feasibility and acceptability of proposed PL interventions. Interviews and focus groups were analysed by thematic analysis and means of representation, respectively. Findings revealed that whilst there was limited understanding about the concept of PL among preschool educators, knowledge of child development was evident and that all participants agreed that there was a need for further training for practitioners. Perceived barriers to promoting PL noted by practitioners included funding, policy, curricular priorities, parental opinions, and the preschool environment. It was recommended that interventions should be: (i) designed using a participatory approach including all key stakeholders, (ii) conducted over the long term, and (iii) incorporate opportunities for children to engage in free and outdoor play. Furthermore, any intervention should be flexible to allow for variation between children's centres, aligned to current policy/children's centre targets and provide training and resources in order to overcome perceived barriers.

The impact of life events and transitions on physical activity: A scoping review

BACKGROUND

Physical activity (PA) is a fluctuating behavior and prone to change across the life course. Changes in PA may be particularly due to the experience of life events and transitions. For well-timed and successful PA interventions, it is important to understand when and why individuals take up or terminate PA.

OBJECTIVES

This scoping review aims to examine the extent, range, and nature of research on the impact of life events and transitions on PA and to summarize key findings.

METHODS

A systematic literature search was conducted in PubMed, PsycINFO, PsycARTICLES, SPORTDiscus, and Web of Science. Articles were included if they had been published in peer-reviewed journals between 1998 and 2020 and assessed the impact of at least one life event or transition on PA.

RESULTS

107 studies that assessed 72 distinct life events and transitions were included and summarized in ten categories. Events and transitions that are primarily associated with decreases in PA were starting cohabitation, getting married, pregnancy, evolving parenthood, and the transitions from kindergarten to primary school, from primary to secondary school, and from high school to college or into the labor market. Retirement was associated with increases in PA; yet, long-term trajectories across retirement indicated a subsequent drop in activity levels. Divorce was associated with no changes in PA. No trends could be identified for changing work conditions, quitting or losing a job, starting a new relationship, widowhood, moving, and diagnosis of illness.

CONCLUSION

Life events and transitions can be conceptualized as natural interventions that occur across the life course and that are oftentimes associated with changes in PA behavior. Our study indicates that, despite some emerging trends, similar events do not necessarily have similar impacts on PA across individuals. It also shows that the research landscape is characterized by a lack of conceptual clarity and by disparate methodologies, making it difficult to synthesize results across studies.

Protocol for a multicenter prospective cohort study evaluating sport activity and development of femoroacetabular impingement in the adolescent hip

BACKGROUND

Femoroacetabular impingement (FAI) is an important cause of hip pain in young and active individuals and occurs as a result of size and shape mismatch between the femoral head and acetabulum. Open physes in children can make hips more susceptible to injury, and high impact forces have been suggested to affect the developing femur. The diagnosis of FAI has recently risen, especially within adolescent populations, and there is an increasing trend towards year-round participation in sports with early specialization. The PREVIEW study is an international longitudinal study designed to determine the association between sport specialization in adolescence and the development of hip impingement.

METHODS

This is a multicentre prospective cohort study evaluating 200 participants between the ages of 12-14 that include sport specialists at the moderate to vigorous physical activity (MVPA) level and non-sport specialists at any activity level. We will monitor physical activity levels of all participants using an activity log and a wrist-mounted activity tracker, with synced data collected every 3 months during the study period. In addition, participants will be evaluated clinically at 6, 12, and 18 months and radiographically at the time of enrolment and 24 months. The primary outcome is the incidence of FAI between groups at 2 years, determined via MRI. Secondary outcomes include hip function and health-related quality of life between subjects diagnosed with FAI versus no FAI at 2 years, as determined by the Hip Outcome Score (HOS) and Pediatric Quality of Life (PedsQL) questionnaires.

DISCUSSION

It is important to mitigate the risk of developing hip deformities at a young age. Our proposed prospective evaluation of the impact of sport activity and hip development is relevant in this era of early sport specialization in youth. Improving the understanding between sport specialization and the development of pre-arthritic hip disease such as FAI can lead to the development of training protocols that protect the millions of adolescents involved in sports annually.

TRIAL REGISTRATION

PREVIEW is registered with clinicaltrials.gov (NCT03891563).

Infants' and toddlers' physical activity and sedentary time as measured by accelerometry: a systematic review and meta-analysis

BACKGROUND

Early experiences in physical activity (PA) are important to shape healthy movement behaviours long-term; as such, it is critical that PA is promoted from infancy, and that detrimental behaviours (e.g., prolonged sedentary time [ST]) are minimized. The purpose of this systematic review and meta-analysis was to examine infants' and toddlers' movement behaviours across daytime hours.

METHODS

Seven online databases were searched for terms related to infants (< 12 months), toddlers (12-35.9 months), PA, ST, and accelerometry. Two independent reviewers examined 4873 articles for peer-reviewed original research, published in English, that assessed infants' (counts/min) and/or toddlers' PA or ST (min/day) using accelerometry across daytime hours. Infants' mean PA level (counts/min) was averaged across studies, and ranges were produced. Estimates of toddlers' movement behaviours were aggregated meta-analytically to produce average daily rates, and accelerometer placement, cut-point validity, device type, and epoch length were tested as a moderating variables.

RESULTS

Twenty-four studies from 16 countries (published 2011-2019), representing 3699 participants, were included in the systematic review. Five studies reported on infants' PA, which ranged from 78.2 to 2580.5 cpm. Across 20 studies, toddlers' total PA, light PA, moderate-to vigorous-intensity PA, and ST ranged from 72.9 to 636.5, 48.5 to 582.4, 6.5 to 89.9, and 172.7 to 545.0 min/day, respectively. After taking into account accelerometer placement, cut-point validity, device type, and epoch length, we found that toddlers engaged in 246.19 min/day (SE = 28.50; 95% CI: 190.34, 302.04) of total PA, 194.10 min/day (SE = 28.76; 95% CI: 137.73, 250.47) of light PA, and 60.16 min/day (SE = 5.88; 95% CI: 48.64, 71.69) of moderate-to vigorous-intensity PA. Toddlers engaged in 337.04 min/day (SE = 32.67; 95% CI: 273.01, 401.07) of ST.

CONCLUSIONS

With limited studies conducted in infants (n = 5), PA estimates are inconclusive and largely heterogeneous. Overall, toddlers tend to exceed the total PA recommendation of 180 min/day; however, very little of this time is spent at higher movement intensities. Even with high PA rates, toddlers still engage in substantial ST. More consistent and valid measurement protocols are needed to improve comparability across studies.

A Longitudinal Study of the Associations of Family Structure with Physical Activity across the Week in Boys and Girls

The aim of this study was to examine how family structure is associated with moderate-to-vigorous-intensity physical activity (MVPA) for children aged between 6 and 11. At 6, 9 and 11 years, children wore an accelerometer and parents/carers completed questionnaires on demographics and family structure. Linear regression models examined cross-sectional associations between family structure and MVPA at age 9 and 11. Linear multilevel models examined longitudinal associations between age 6 and 11, differences in change over time were examined using interaction terms. No associations between exposures and MVPA were evident at age 9. Compared to boys living in one home, eleven-year-old boys who lived in multiple homes performed 15.99 (2.46-29.52) fewer minutes of MVPA on weekend days. In longitudinal analyses, the evidence was unclear whether the association with family structure changed over time. Models that assumed associations with family structure remained constant over time, found that boys who lived in multiple homes performed 11.02 (0.76-21.28) fewer minutes of MVPA per weekend day, while for each additional sibling, girls performed an extra 1.89 (0.25-3.53) minutes of MVPA per weekend day. Findings indicate a small number of associations, varying in magnitude, between family structure and children's MVPA. Therefore, families of all structures should be supported to help their children meet MVPA recommendations.

Changes in volume and bouts of physical activity and sedentary time across early childhood: a longitudinal study

BACKGROUND

Understanding changes in physical activity and sedentary time (SED) during early childhood may provide insights into how to effectively promote a healthy start to life. This study examined changes in total volume and bouts of SED, light- (LPA), and moderate- to vigorous-intensity physical activity (MVPA) across early childhood, and explored differences in change between boys and girls.

METHODS

Data were drawn from 330 children participating in the Melbourne InFANT Program, collected between 2008 and 2013 and analysed in 2017. Children's physical activity and SED were assessed for at least 7 days at each timepoint using ActiGraph GT1M accelerometers at 19 months, 3.5 and 5 years of age. Total volume of SED (≤100 counts per minute [CPM]), LPA (101-1680 CPM) and MVPA (≥1681 CPM) were expressed as a percentage of wear time, and the frequency (number of bouts/day) and duration (mins/bout) of SED, LPA and MVPA bouts ≥1 min were calculated at each time point. Multilevel models with random intercepts and slopes were used to examine changes in total volume and bouts of SED, LPA and MVPA for boys and girls.

RESULTS

Compared to aged 19 months, children's total volume of SED and LPA decreased at 3.5 and 5 years old, while MVPA increased. The frequency of SED bouts at 3.5 and 5 years was greater than at 19 months, but the duration was shorter. Additionally, the frequency and duration of LPA bouts was lower and MVPA bout frequency and duration was greater at 3.5 and 5 years. In general, there was no evidence of sex differences in trajectories of children's physical activity and SED. However, variations in trajectory were observed at the individual child level.

CONCLUSIONS

Children's total volume and bouts of SED, LPA and MVPA change across early childhood, mostly in a favourable direction. Trajectories appear to be similar for boys and girls. Investigation of individual variation in trajectories is likely to provide greater insight into associations between physical activity and future health and behavioural outcomes.

A closer look at the relationship among accelerometer-based physical activity metrics: ICAD pooled data

BACKGROUND

Accelerometers are widely used to assess child physical activity (PA) levels. Using the accelerometer data, several PA metrics can be estimated. Knowledge about the relationships between these different metrics can improve our understanding of children's PA behavioral patterns. It also has significant implications for comparing PA metrics across studies and fitting a statistical model to examine their health effects. The aim of this study was to examine the relationships among the metrics derived from accelerometers in children.

METHODS

Accelerometer data from 24,316 children aged 5 to 18 years were extracted from the International Children's Accelerometer Database (ICAD) 2.0. Correlation coefficients between wear time, sedentary behavior (SB), light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA), moderate- and vigorous-intensity PA (MVPA), and total activity counts (TAC) were calculated.

RESULTS

TAC was approximately 22X103 counts higher (p < 0.01) with longer wear time (13 to 18 h/day) as compared to shorter wear time (8 to < 13 h/day), while MVPA was similar across the wear time categories. MVPA was very highly correlated with TAC (r = .91; 99% CI = .91 to .91). Wear time-adjusted correlation between SB and LPA was also very high (r = -.96; 99% CI = -.96, - 95). VPA was moderately correlated with MPA (r = .58; 99% CI = .57, .59).

CONCLUSIONS

TAC is mostly explained by MVPA, while it could be more dependent on wear time, compared to MVPA. MVPA appears to be comparable across different wear durations and studies when wear time is ≥8 h/day. Due to the moderate to high correlation between some PA metrics, potential collinearity should be addressed when including multiple PA metrics together in statistical modeling.

Detection of Pediatric Upper Extremity Motor Activity and Deficits With Accelerometry

IMPORTANCE

Affordable, quantitative methods to screen children for developmental delays are needed. Motor milestones can be an indicator of developmental delay and may be used to track developmental progress. Accelerometry offers a way to gather real-world information about pediatric motor behavior.

OBJECTIVE

To develop a referent cohort of pediatric accelerometry from bilateral upper extremities (UEs) and determine whether movement can accurately distinguish those with and without motor deficits.

DESIGN, SETTING, AND PARTICIPANTS

Children aged 0 to 17 years participated in a prospective cohort from December 8, 2014, to December 29, 2017. Children were recruited from Ranken Jordan Pediatric Bridge Hospital, Maryland Heights, Missouri, and Washington University School of Medicine in St Louis, St Louis, Missouri. Typically developing children were included as a referent cohort if they had no history of motor or neurological deficit; consecutive sampling and matching ensured equal representation of sex and age. Children with diagnosed asymmetric motor deficits were included in the motor impaired cohort.

EXPOSURES

Bilateral UE motor activity was measured using wrist-worn accelerometers for a total of 100 hours in 25-hour increments.

MAIN OUTCOMES AND MEASURES

To characterize bilateral UE motor activity in a referent cohort for the purpose of detecting irregularities in the future, total activity and the use ratio between UEs were used to describe typically developing children. Asymmetric impairment was classified using the mono-arm use index (MAUI) and bilateral-arm use index (BAUI) to quantify the acceleration of unilateral movements.

RESULTS

A total of 216 children enrolled, and 185 children were included in analysis. Of these, 156 were typically developing, with mean (SD) age 9.1 (5.1) years and 81 boys (52.0%). There were 29 children in the motor impaired cohort, with mean (SD) age 7.4 (4.4) years and 16 boys (55.2%). The combined MAUI and BAUI (mean [SD], 0.86 [0.005] and use ratio (mean [SD], 0.90 [0.008]) had similar F1 values. The area under the curve was also similar between the combined MAUI and BAUI (mean [SD], 0.98 [0.004]) and the use ratio (mean [SD], 0.98 [0.004]).

CONCLUSIONS AND RELEVANCE

Bilateral UE movement as measured with accelerometry may provide a meaningful metric of real-world motor behavior across childhood. Screening in early childhood remains a challenge; MAUI may provide an effective method for clinicians to measure and visualize real-world motor behavior in children at risk for asymmetrical deficits.

Physical activity among Norwegian preschoolers varies by sex, age, and season

BACKGROUND

Knowledge of physical activity (PA) in preschool populations is important for public health promotion. We investigated levels of PA in a large sample of Norwegian preschoolers and explored variations and development in PA by sex, age, and season.

METHODS

Physical activity levels of 1154 children (mean age 4.7 years, 52% boys) were measured by accelerometry (ActiGraph GT3X+) for 14 consecutive days between autumn 2015 and summer 2016. Additionally, 330 children provided up to 3 repeated measurements of PA across seasons. A linear mixed model was applied to analyze associations and interactions of total PA (cpm), light PA (LPA), moderate PA (MPA), vigorous PA (VPA), moderate-to-vigorous PA (MVPA), sedentary time (SED), sex, age, and season.

RESULTS

Boys and girls spent mean (standard deviation) 72 (21) and 59 (18) min/d in MVPA and had a total PA of 790 (202) and 714 (192) cpm/d, respectively. Boys had higher PA levels than girls, PA increased with age, and PA was higher during spring/summer than autumn/winter (P < 0.001). Boys had a greater increase in PA by age than girls (P < 0.05), mainly due to increased MVPA during spring/summer (p for sex × age × season=0.009).

CONCLUSIONS

Boys were consistently more active and less sedentary than girls, and PA increased with age for both sexes. Boys exhibited a greater increase than girls in PA by age, and PA differed across seasons, with higher levels of MVPA during spring/summer. Differences in MVPA between boys and girls, among age groups, and among seasons seem to be interrelated, indicating that many factors influence preschoolers' PA.

Parenting Intervention to Improve Nutrition and Physical Activity for Preschoolers with Type 1 Diabetes: A Feasibility Study

OBJECTIVE

This study reports the feasibility and acceptability of a healthy eating and physical-activity-focused behavioral intervention for parents of young children with type 1 diabetes (T1D).

METHODS

Ten parents of young children (age 2-5 years) with T1D enrolled. The intervention included six behavioral sessions (five by telephone), diabetes nursing consultation, parent coach contact, text messages, and a study website. Analyses explored feasibility, acceptability, and preliminary findings.

RESULTS

There was evidence of high acceptability (mean parent satisfaction = 1.11, very satisfied). Although most participants completed all of the assessments, there were some barriers to data collection devices. The number of participants within the American Diabetes Association recommended glycemic range doubled; there was no significant change in hemoglobin A1c, diet, or physical activity.

CONCLUSION

There was evidence of feasibility and acceptability and initial evidence of change in hypothesized directions. Minor changes were made for the larger randomized controlled trial.

Physical activity and sedentary behavior in preschoolers: a longitudinal assessment of trajectories and determinants

BACKGROUND

Despite physical activity (PA) being recognized as a critically important factor for good physical and mental health already early in life and throughout the life course, prospective data on activity behavior during the preschool years remains scarce. This study examined trajectories and determinants of levels and change in total PA (TPA), moderate-to-vigorous PA (MVPA) and sedentary behavior (SB) in a representative sample of Swiss preschoolers.

METHODS

Data were drawn from the Swiss Preschoolers' Health Study (SPLASHY), a multi-site prospective cohort study including 555 children (53% boys) aged 2-to-6 years at baseline. A follow-up was conducted after 12 months. Activity behavior was measured using accelerometers. Information on 35 potential determinants from different socio-ecological domains was either directly measured or parent-reported. Trajectories of TPA, MVPA and SB over time were described for boys and girls. Linear mixed models were used to investigate factors that predicted levels and change in TPA, MVPA and SB.

RESULTS

All children were sufficiently physically active according to published recommendations for preschoolers. Trajectory profiles revealed a marked increase in TPA and MVPA in boys and girls whereas SB remained fairly stable over time. Mixed modeling demonstrated that variables most relevant to determining PA levels were sex, age and activity temperament (all positively associated). Together with gross motor skills, birth weight, family structure (only for TPA) and season (only for MVPA), these factors accounted for 26 and 32% of total variance explained in TPA and MVPA, respectively. Activity temperament emerged as the strongest determinant of SB (negative association) and explained with sex, season and family structure 20% of total variance in SB. The presence of older siblings was the only factor that predicted change in PA over time.

CONCLUSIONS

In this healthy physically active cohort of preschoolers, non-modifiable individual-level factors had the greatest influence on PA. The limited success of this and previous studies to identify modifiable determinants and the finding that most preschoolers were sufficiently active suggest that future attempts should provide insights into how preschoolers' activity levels can be maintained and fostered to prevent subsequent harmful declines attributable, amongst others, to educational transitions. Thus, good-quality longitudinal studies are needed.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN41045021 (date of registration: 21.03.14).

Physical activity and sedentary time during childcare outdoor play sessions: A systematic review and meta-analysis

Outdoor playtime has been highly correlated with moderate-to vigorous-intensity physical activity (MVPA), while also being associated with decreased sedentary time. This systematic review and meta-analysis sought to examine the physical activity levels and sedentary time of young children (2-5years) during outdoor play periods at centre-based childcare. Eight online databases were searched for peer-reviewed, English-language, original research. Two reviewers independently extracted data (study design, participants, method of measurement, and physical activity and/or sedentary time of participants). Time spent in outdoor activity intensities were converted to percentage of time, and averaged across the two measurement types: accelerometry and observational. Of the 26 included articles, 11 used accelerometry, 13 employed direct observation, and 2 adopted a combination of both measurement methods. Average percentage of time engaged in MVPA and sedentary pursuits ranged from 6.7% to 43% and 23.2% to 63.5% by accelerometry, and 2% to 53.9% and 46.1% to 80.2% by observation, respectively. Total physical activity (only measured by accelerometry) ranged from 23.2% to 63.5% of outdoor playtime. Meta-analysis of 11 accelerometer studies found that children spent a mean (95% CI) of: 13.99% (10.35-17.63) of outdoor playtime in MVPA, 43.77% (32.95-54.58) in TPA, and 52.81% (44.1-61.51) in sedentary time. Overall, young children have the potential to be highly active during outdoor play sessions at centre-based childcare; however, many children still engage in substantial amounts of sedentary time. Future research should explore the frequency and/or duration of outdoor time which best support young children's physical activity and limits sedentary time in childcare.

Impact of parents' physical activity on preschool children's physical activity: a cross-sectional study

Purpose

This study examined the associations of physical activity levels between parents and their pre-school children based on gender and weekday/weekend.

Method

A total of 247 parent-preschool child triads from Shanghai, China were analyzed. The children had a mean age of 57.5 ± 5.2 months. Both sedentary behavior and physical activity were measured in all participants using an ActiGraph GT3X⁺ accelerometer over seven consecutive days from Monday through the following Sunday. A multivariate regression model was derived to identify significant relationships between parental and child physical activity according to gender and weekday/weekend.

Results

There was a significant correlation between mothers’ and girls’ moderate-to-vigorous physical activity (MVPA) and total physical activity (TPA) on weekdays. Fathers’ MPVA levels correlated significantly with those of boys and girls, with paternal influence appearing to be stronger than maternal influence. However, there was not a significant correlation between fathers’ and children’s TPA. TPA levels of both mothers and fathers correlated with those of girls, but not with those of boys. Parental sedentary levels on the weekend correlated significantly with girls’ levels, but not with boys’ levels. Children’s physical activity levels on weekends were influenced more by fathers’ activity levels than by mothers’, while the opposite was observed on weekdays.

Conclusion

Sedentary behavior and physical activity levels of parents can strongly influence those of their preschool children, with maternal influence stronger during the weekdays and paternal influence stronger on the weekends. Parents’ activity levels influence girls’ levels more strongly than they influence boys’ levels.

Prolonged elevated body mass index in preschool children after the Great East Japan Earthquake

BACKGROUND

The Great East Japan Earthquake followed by tsunamis and the Fukushima Daiichi Nuclear Power Plant (NPP) accident caused catastrophic damage. The effects of the disaster on the growth of affected children are of great concern but remain unknown.

METHODS

The subject group was derived from two Japanese nationwide retrospective cohorts (historical control and exposure groups, respectively). The exposure group experienced the disaster at 47-59 months of age. We analyzed longitudinal changes in standard deviation score (SDS) for height and body mass index (BMI) using normal Japanese children's standards. Moreover, we analyzed the details of the affected children in Fukushima using Fukushima-specific growth charts established with the historical control data to clarify any indirect effect of the disaster on growth.

RESULTS

Affected children in Fukushima had significantly higher BMI SDS than the historical control group (difference, 0.13; 95% CI: 0.044-0.21, P = 0.0029) and the regional controls (difference, 0.14; 95% CI: 0.074-0.20, P < 0.0001) 1.5 years after the disaster. Similar sustained increases in BMI SDS were also found with Fukushima-specific growth charts, but the phenomenon was detected only in boys. Notably, the BMI SDS of affected children who lived near the NPP had been increasing after the disaster, whereas those in distant areas had not changed. In contrast, height SDS had not changed throughout the analysis.

CONCLUSIONS

Prolonged elevated BMI SDS was detected only in affected children in Fukushima. This phenomenon may be explained by an indirect effect of the NPP accident.

Change in children's physical activity and sedentary time between Year 1 and Year 4 of primary school in the B-PROACT1V cohort

BACKGROUND

The aim of this study was to examine how children's and parents' physical activity changes from Year 1 (5-6) to Year 4 (8-9 years of age).

METHODS

Data are from the Bristol (UK) B-PROACT1V cohort. Fifty-seven primary schools were recruited when the children were in Year 1, with 1299 children and their parents providing data. Forty-seven schools were re-recruited in Year 4, with 1223 children and parents providing data (685 of whom participated in Year 1). Children and at least one parent wore an accelerometer for 5 days including a weekend and mean minutes of sedentary time, moderate-to-vigorous intensity physical activity (MVPA) and accelerometer counts per minute (CPM) were derived. Multiple imputation was used to impute missing data for all 1837 families who took part, including those who participated at just one time. Paired t-tests examined if there was statistical evidence of change in accelerometer measures.

RESULTS

Multiple imputation and observed data were comparable and results using complete observed data were mostly the same as those using imputed data. Imputed data showed that mean boys' CPM decreased from 747 to 673 (difference in mean 74 [95% CI 45 to 103]) and girls' from 686 to 587 (99 [79 to 119]). Boys' time spent in MVPA reduced from 72 to 69 (3 [0 to 6]) and girls' from 62 to 56 (7 [4 to 9]) minutes per day. There were increases in sedentary time for both boys (354 to 428 min, 74 [61 to 88]) and girls (365 to 448, 83 [71 to 96]). There was no evidence of change in parent CPM or MVPA. Mothers' sedentary time increased by 26 min per day [16 to 35].

CONCLUSIONS

There were similar increases in sedentary time in girls and boys between age 5-6 and 8-9, and decreases in MVPA that were more marked in girls. The similarity of multiple-imputed and complete observed data suggest that these findings may not be markedly affected by selection bias. Result support early interventions to prevent the age-related decline in children's physical activity.

Parent's Physical Activity Associated With Preschooler Activity in Underserved Populations

INTRODUCTION

In the U.S., children from low-income families are more likely to be obese. The impact of parent modeling of physical activity (PA) and sedentary behaviors in low-income American ethnic minorities is unclear, and studies examining objective measures of preschooler and parent PA are sparse.

METHODS

This cross-sectional study examined 1,003 parent-child pairs who were of low income, largely Latino and African American, and living in one of two geographically disparate metropolitan areas in the U.S. Parents and children wore GT3X/GT3X+ accelerometers for an average of >12 hours/day (7:00am-9:00pm) for 1 week (September 2012 to May 2014). Analysis occurred in 2015-2016.

RESULTS

About 75% of children were Latino and >10% were African American. Mean child age was 3.9 years. The majority of children (60%) were normal weight (BMI ≥50th and <85th percentiles), and more than a third were overweight/obese. Children's total PA was 6.03 hours/day, with 1.5 hours spent in moderate to vigorous PA (MVPA). Covariate-adjusted models showed a monotonic, positive association between parent and child minutes of sedentary behavior (β=0.10, 95% CI=0.06, 0.15) and light PA (β=0.06; 95% CI=0.03, 0.09). Child and parent MVPA were positively associated up to 40 minutes/day of parent MVPA, but an inverse association was observed when parental MVPA was beyond 40 minutes/day (p=0.002).

CONCLUSIONS

Increasing parental PA and reducing sedentary behavior correlate with increased PA-related behaviors in children. However, more work is needed to understand the impact of high levels of parental MVPA on the MVPA levels of their children.

School-time physical activity among Arab elementary school children in Qatar

Background

Recent data from a self-administered questionnaire show that approximately 75% of school children in Qatar do not meet the daily recommended levels of physical activity (PA). Since children spend half of their waking hours in school, it is important to understand when and how much PA children accumulate during the school day. This study aimed to objectively assess school-time PA among elementary school children in Qatar and to determine association of PA with age, gender, body mass index (BMI) status, or day of the week.

Methods

A cross-sectional epidemiological study was conducted in four randomly selected elementary schools in Qatar. Two classes representing grade 1 children (age 5) and grade 4 children (age 9) were randomly selected within each school. A total of 183 elementary school children (86 boys and 97 girls) ages 6–12 years participated in this study. PA was assessed using a three-axial accelerometer (ActiGraph® wGT3X-BT). Participants wore accelerometers on their non-dominant wrist at school (7:00 a.m. to 1:00 p.m.) for five consecutive school days during the week. A cutoff points of 818 counts per 5 s was classified as moderate-to-vigorous physical activity (MVPA).

Results

The average duration of MVPA in our study was 28.2 ± 13.5 min per day. Only 39% of participated children reach the recommended school-based MVPA of 30 min or more per day. Students spent on average 58.1 ± 8.4% of school time on sedentary activities. MVPA of boys and girls was similar in age 5 while girls age 9 were less active (23.7 ± 1.5 min/day) than boys of the same age (42.7 ± 1.8 min/day), ES = 0.269, P < 0.001. Neither overweight children nor children at risk for being overweight showed any differences in physical activity parameters when compared to children of normal weight. Our results showed, percentage of MVPA on the first (7.7 ± 5.1%) and last (7.1 ± 4.1%) day of the week was generally lower compared to other weekdays (P < 0.001).

Conclusion

This was the first study to objectively assess PA during school hours among elementary school-children in Qatar. This study found that many of school children do not perform sufficient time being physically active at school. All students in two age categories (age 5 and age 9) spend the majority of school time engaged in sedentary activities. The low participation of girls age 9 in MVPA is a cause for concern and need to be addressed.

Potential selection effects when estimating associations between the infancy peak or adiposity rebound and later body mass index in children

INTRODUCTION

This study aims to evaluate a potential selection effect caused by exclusion of children with non-identifiable infancy peak (IP) and adiposity rebound (AR) when estimating associations between age and body mass index (BMI) at IP and AR and later weight status.

SUBJECTS AND METHODS

In 4744 children with at least 4 repeated measurements of height and weight in the age interval from 0 to 8 years (37 998 measurements) participating in the IDEFICS (Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants)/I.Family cohort study, fractional polynomial multilevel models were used to derive individual BMI trajectories. Based on these trajectories, age and BMI at IP and AR, BMI values and growth velocities at selected ages as well as the area under the BMI curve were estimated. The BMI growth measures were standardized and related to later BMI z-scores (mean age at outcome assessment: 9.2 years).

RESULTS

Age and BMI at IP and AR were not identifiable in 5.4% and 7.8% of the children, respectively. These groups of children showed a significantly higher BMI growth during infancy and childhood. In the remaining sample, BMI at IP correlated almost perfectly (r⩾0.99) with BMI at ages 0.5, 1 and 1.5 years, whereas BMI at AR correlated perfectly with BMI at ages 4-6 years (r⩾0.98). In the total study group, BMI values in infancy and childhood were positively associated with later BMI z-scores where associations increased with age. Associations between BMI velocities and later BMI z-scores were largest at ages 5 and 6 years. Results differed for children with non-identifiable IP and AR, demonstrating a selection effect.

CONCLUSIONS

IP and AR may not be estimable in children with higher-than-average BMI growth. Excluding these children from analyses may result in a selection bias that distorts effect estimates. BMI values at ages 1 and 5 years might be more appropriate to use as predictors for later weight status instead.

Comparing physical activity and sedentary time among overweight and nonoverweight preschoolers enrolled in early learning programs: a cross-sectional study

Establishing appropriate physical activity and sedentary behaviours during early childhood is important to ensure children accrue the many associated health benefits. While physical activity levels have been reported as low within early learning programs, little research has explored the physical activity and sedentary time of Canadian preschoolers classified as overweight within these facilities. The purpose of this study was to compare objectively measured physical activity and sedentary time among preschoolers classified as overweight and nonoverweight in early learning programs. Direct assessment of physical activity and sedentary time of 216 preschool-aged children was collected via Actical accelerometers during early learning hours, while body mass index percentile was calculated based on preschoolers’ objectively measured height and weight. Results of three 3-way ANOVAs suggest that rates of moderate to vigorous physical activity, total physical activity, and sedentary time (p > 0.05) did not significantly differ based on weight status, sex, and type of early learning facility. This study is one of few that has examined differences in overweight and nonoverweight preschoolers’ sedentary time, and adds to the limited research exploring physical activity levels among overweight and nonoverweight preschoolers during early learning hours. Given the high rates of sedentary time reported, programming within early learning facilities is necessary to support preschoolers, regardless of weight status, to achieve increased physical activity levels and decreased sedentary time.

Physical Activity During the Early Years: A Systematic Review of Correlates and Determinants

CONTEXT

Being physically active during the early years (age 0-6 years) is vital for healthy development. Identifying correlates and determinants of physical activity (PA) is crucial to guide effective interventions. This systematic review synthesized studies investigating potential correlates and determinants of PA during the early years, accounting for different types of PA assessment.

EVIDENCE ACQUISITION

Nine electronic databases were searched from inception year (1900) until September 2014; data were analyzed/interpreted in April 2015. The following inclusion criteria were used: written in English, published in peer-reviewed journals, participants not in statutory/school education, and an observational design investigating associations between an exposure/variable, and a quantitative measure of PA. Correlates/determinants of total, moderate to vigorous, and light PA were reported using an ecologic model.

EVIDENCE SYNTHESIS

Of 22,045 identified studies, 130 were included. All took place in high-income countries and few (6%) were of high quality. Correlates of total PA were sex (male, ++); parental PA (+); parental support (+); and time outdoors (+). Determinants of total PA were sex (+) and time spent playing with parents (+). The only correlate of moderate to vigorous PA was sex (male, ++). No determinants of moderate to vigorous or light PA were found. PA correlates/determinants were relatively consistent between objective and subjective PA measures.

CONCLUSIONS

Numerous studies investigated potential correlates and determinants of PA, but overall quality was low. A small number of demographic/biological and social/cultural factors were associated with PA. There is a need for high-quality studies exploring correlates/determinants across all domains of the ecologic model.

Physical activity and screen use policy and practices in childcare: results from a survey of early childhood education services in New Zealand

OBJECTIVE

To investigate written policies, equipment, strategies and barriers to children's activity in early childhood education settings, including participation in health promotion programs and reported time children spend in active play and using screens while in care.

METHODS

Cross-sectional online survey of licensed childcare services in Auckland and Waikato. Policies were scored using a validated tool (WellCCAT-NZ). Results were analysed using descriptive statistics and multivariate regression.

RESULTS

Managers, head teachers or similar from 237 services completed the survey (28% of invited services). Of these, 35% had a written activity policy; most policies scored low on the WellCCAT-NZ. Comprehensive and strongly worded policies were associated with a lower adult-to-child ratio (p=0.03, adjusted for ECE characteristics). No policies addressed screen use. Children were reported to have teacher-led activity 80 minutes/day, and child-led activity five hours/day (indoor and outdoor). Children watched television daily in 2% and weekly in 11% the services; and used computers daily in 11% and weekly in 22% of services. Fewer than half of services participated in health promotion programs with a physical activity component.

CONCLUSIONS

Childcare services reported having adequate equipment, space and time for physical activity of children; however, there are low participation rates in activity programs and a notable absence of written policy.

Correlates of Physical Activity in Latino Preschool Children Attending Head Start

BACKGROUND

Physical activity is associated with long-term benefits for health and tracks from early childhood into later adolescence. Limited information exists about factors influencing physical activity among Latino preschoolers. We aimed to identify correlates of objectively measured light-to-vigorous-intensity physical activity as a proportion of wear time (% PA) in Latino 3-5 year olds.

METHODS

Latino preschoolers (n = 96) were recruited from Head Start centers in Houston, TX, USA, from 2009 to 2010. Sociodemographics, anthropometrics, acculturation, neighborhood disorder, and TV viewing were measured. Actigraph GT1M accelerometers measured physical activity. Block linear regression was used with % PA as the dependent variable.

RESULTS

Children achieved 285.7 ± 58.0 min/day of PA. In the final adjusted-model, child age, parental education and neighborhood disorder were positively associated with % PA (beta = 0.33, p = .002; beta = 0.25, p = .038; beta = 0.22, p = .039, respectively). TV viewing was inversely associated with % PA (beta=-0.23, p = .027).

CONCLUSION

The majority of Latino preschoolers in our study exceeded US national and international guidelines of physical activity duration. Future interventions to sustain physical activity should focus on the influence of age, socioeconomic status, neighborhood disorder, and TV viewing on Latino preschoolers' attainment of physical activity.

Young children with type 1 diabetes: challenges, research, and future directions

The incidence of type 1 diabetes (T1D) in young children (age <6 years) is rising. Diabetes management guidelines offered by the American Diabetes Association and health care teams understandably place a high burden of responsibility on caregivers to check young children's blood glucose levels, administer insulin, and monitor diet and physical activity with the ultimate goal of maintaining tight glycemic control. Unfortunately, this tight control is needed during a vulnerable developmental period when behavior is unpredictable, T1D can be physiologically difficult to control, parenting stress can be elevated, and caregivers are strained by normal child caretaking routines. Despite the potentially different management needs, specific education and clinical services for managing diabetes in young children are rarely offered, and behavioral research with this young child age group has been limited in scope and quantity. Research findings pertinent to young children with T1D are reviewed, and potential clinical implications, as well as areas for future research, are discussed.