Methodological considerations in using accelerometers to assess habitual physical activity in children aged 0-5 years

A systematic review of proxy-report questionnaires assessing physical activity, sedentary behavior and/or sleep in young children (aged 0-5 years)

BACKGROUND

Accurate proxy-report questionnaires, adapted to the child's developmental stage, are required to monitor 24-h movement behaviors in young children, especially for large samples and low-resource settings.

OBJECTIVES

This review aimed to summarize available studies evaluating measurement properties of proxy-report questionnaires assessing physical activity, sedentary behavior and/or sleep in children aged 0-5 years.

METHODS

Systematic literature searches were carried out in the PubMed, Embase and SPORTDiscus databases, up to January 2021. For physical activity and sedentary behavior questionnaires this is a review update, whereas for sleep questionnaires we included all relevant studies published up to now. Studies had to evaluate at least one of the measurement properties of a proxy-report questionnaire assessing at least duration and/or frequency of physical activity, sedentary behavior and/or sleep in 0- to 5-year-old children. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guideline was used to evaluate the quality of evidence.

RESULTS

Thirty-three studies were included, examining a total of 37 questionnaires. Ten questionnaires were designed for infants, two for toddlers, 11 for preschoolers, and 14 for a broader age range targeting multiple of these age groups. Twenty questionnaires assessed constructs of sleep, four assessed constructs of physical activity, two assessed screen behavior, five assessed constructs of both physical activity and sedentary behavior, and six assessed constructs of all 24-h movement behaviors. Content validity was evaluated for six questionnaires, structural validity for two, internal consistency for three, test-retest reliability for 16, measurement error for one, criterion validity for one, and construct validity for 26 questionnaires. None of the questionnaires were considered sufficiently valid and/or reliable for assessing one or more movement behaviors in 0- to 5-year-old children, and the quality of evidence was mostly low or very low.

CONCLUSIONS

Valid and/or reliable questionnaires assessing 24-h movement behaviors in 0- to 5-year-olds are lacking. High-quality studies are therefore required, to develop proxy-report questionnaires and evaluate their measurement properties.

PROSPERO REGISTRATION NUMBER

CRD42020169268.

Evaluation of a Proposal for Movement Integration in the Teaching-Learning Process in Early Childhood Education

Physical activity is essential to child development, but studies show that children are increasingly inactive. Due to schools being considered privileged environments to promote physical activity, the aim of this study was to increase the physical activity performed by early childhood education children during the school day by integrating movement into academic content and analyze this process. The amount and intensity of physical activity performed by a group of 24 3-4-year-old children in three different weeks were measured by accelerometry: one week with the methodology they had been following (week 1); and two weeks in which movement was integrated into the content through a specific proposal (week 2) and the same improved proposal (week 3). The results reveal that the application of a movement integration program not only allowed students to work on academic content in a physically active way, but also significantly increased the amount of physical activity that children performed during the school day. However, it was necessary to carry out several interventions the same day, or make movement integration the reference methodology, to meet the minimum recommended physical activity levels. In addition, to increase their effectiveness, interventions should be continually reviewed and improved to increase the motor engagement time.

Demographic Correlates of Movement Behaviors in Infants: A Longitudinal Study

BACKGROUND

Demographic correlates of movement behaviors in infants are unclear. This study examined the longitudinal associations between demographic correlates and movement behaviors in infants.

METHODS

Participants were 411 parents of infants from the Early Movers project in Edmonton, Canada. Movement behaviors, infant and parental age, and nonparental care time were assessed using a parental questionnaire at 2, 4, and 6 months of age. Other infant and parental demographic variables were assessed at 2 months of age. Linear and generalized linear mixed models were conducted.

RESULTS

Infant age was associated with all movement behaviors except for restrained time. White infants and those with older parents had less tummy time but increased odds of having reading time. Infants of the most educated parents also had lower tummy time. Higher parental education and more siblings were associated with no screen time and longer infant sleep time. Infants with immigrant parent(s) were less likely to have reading time. No associations were found for infant sex, time spent in nonparental care, and parental marital status.

CONCLUSION

Since no single demographic group demonstrated healthy patterns for all movement behaviors, promotion of a healthy balance of movement behaviors may be needed universally for all infants.

Prevalence of Physical Activity, Screen Time, and Sleep, and Associations with Adiposity and Motor Development among Preschool-Age Children in Vietnam: The SUNRISE Vietnam Pilot Study

OBJECTIVES

Global childhood obesity is of great concern. In 2019, the World Health Organization released global guidelines on movement behaviors for the children under 5 y of age to combat this epidemic. This study aimed to estimate the prevalence of Vietnamese preschoolers meeting the guidelines, and examined whether guideline compliance is associated with adiposity and motor development.

METHODS

A cross-sectional study was conducted on 103 healthy preschoolers who were conveniently sampled from preschools in urban and rural areas around Ho Chi Minh city. Time spent in different intensities of physical activity and sedentary behavior was measured using Actigraph GT3X + accelerometers over three consecutive days. Sleep and screen time were obtained via parent questionnaires. Children were classified as meeting or not meeting the global guidelines. Height, weight, and motor skills were measured by the research staff. Regression models were applied to quantify the association between guideline compliance and adiposity and motor development, adjusting for age and sex.

RESULTS

While 17.5% of children met all three guidelines, 5.8% met no guidelines. The prevalences of children who met guidelines for physical activity time, sleep duration, and screen time were 50.4%, 81.4%, and 44.7%, respectively. There was no association between guideline compliance and adiposity and motor development.

CONCLUSION

This study found a low proportion of children who met the global guidelines, whereas a high proportion of those with overweight and obesity was reported. Health programs should promote more physical activities of various intensities in young children.

Prospective associations between dietary patterns, screen and outdoor play times at 2 years and age at adiposity rebound: The EDEN mother-child cohort

Although an early adiposity rebound (AR) is an established risk factor for later obesity, little is known regarding its determinants, especially modifiable ones. Using data from the French EDEN mother–child cohort (1903 children born in 2003–2006), we aimed to examine the association between diet and activity-related behaviors at 2 years of age and the timing of the AR. Two-year-old children (n = 1138) with parent-reported data on their foods/drinks intake, TV/DVD watching time, outdoor playtime, and with an estimated (via growth modelling) age at AR were included in the present study. Two dietary patterns, labelled 'Nutrient-dense foods' and 'Processed and fast foods', were identified in a previous study. Multivariable linear and logistic regression models were used to assess the association between dietary patterns and activity-related behaviors and, respectively, the age at AR (continuous) and the likelihood of having a very early AR (before 3.6 years for girls and 3.8 years for boys, i.e., below the 10th percentile of sex-specific distribution). A higher score on the ‘Processed and fast foods’ dietary pattern was associated with a higher likelihood of having a very early AR (OR = 1.23; 95% CI: 1.00 to 1.50). No significant association was observed between the ‘Nutrient-dense foods’ dietary pattern, TV/DVD watching and outdoor playing times and the timing of the AR. This finding emphasizes the importance of reducing nutrient-dense and processed foods from the early years of life, and provides further support for early interventions aimed at helping parents establish healthy eating habits for their growing child from the complementary period.

Cross-validation of cut-points in preschool children using different accelerometer placements and data axes

The present study cross-validated various cut-points to assess physical activity and sedentary behaviour in preschoolers, using hip- and wrist-worn accelerometers and both vertical axis and vector magnitude data. Secondly, we examined the influence of epoch length on time estimates of physical activity and sedentary behaviour. Sixty-four preschoolers (34 girls) wore two accelerometers, on their right hip and dominant wrist, during 1 hour of free play. Preschoolers' activities were observed by two trained researchers. Area under the curve (AUC) was calculated for the receiving operating characteristic (ROC) curves as a measure of precision. AUC ranges were 0.603-0.723 for sedentary behaviour, 0.472-0.545 for light physical activity and 0.503-0.661 for moderate-to-vigorous physical activity (MVPA), indicating poor to fair precision. Percentage of time classified as sedentary behaviour, light or MVPA according to observation and accelerometer data varied largely between cut-points, accelerometer placements and axes. The influence of epoch length on time estimates was minimal across cut-points, except for one hip-based vector magnitude cut-point. Across all accelerometer placements and data axes, no set of cut-points demonstrated adequate precision for sedentary behaviour, light physical activity and MVPA. The highly variable and omnidirectional activity pattern of preschoolers may explain the lack of adequate cut-points.

Longitudinal Associations Between Device-Measured Physical Activity and Early Childhood Neurodevelopment

BACKGROUND

The aim of this study was to investigate longitudinal associations between physical activity and early childhood neurodevelopment.

METHODS

Data from 1673 children from the 2015 Pelotas (Brazil) birth cohort study were analyzed. Physical activity was measured using accelerometers on the wrist at ages 1, 2, and 4 years. Neurodevelopment was measured using the Battelle Development Inventory at age 4 years. Linear regression models were used to test trajectories and cumulative associations of physical activity with child neurodevelopment.

RESULTS

Of the 3 physical activity trajectories observed, children in the medium (β = 1.17; 95% confidence interval, 0.25 to 2.10) and high (β = 2.22; 95% confidence interval, 0.61 to 3.82) trajectories showed higher neurodevelopment scores than children in the lower activity trajectory. Cumulative analyses showed that children in the highest tertile of physical activity in all follow-ups presented a mean neurodevelopment score 4.57 (95% confidence interval, 2.63 to 6.51) higher than children in the lowest tertile in all follow-ups. All analyses showed a dose-response characteristic of association, with higher physical activity indicating higher neurodevelopment scores.

CONCLUSIONS

Physical activity may be an important predictor of neurodevelopment through early childhood.

Cognitively Engaging Physical Activity for Targeting Motor, Cognitive, Social, and Emotional Skills in the Preschool Classroom: The Move for Thought preK-K Program

Despite the growing body of research indicating that integrated physical activity with learning benefits children both physically and cognitively, preschool curricula with integrated physical activities are scarce. The "Move for Thought (M4T) preK-K" program provides activities on fundamental motor skills that are integrated with academic concepts, executive function, and social-emotional skills in the preschool environment. The aim of this study was to evaluate the feasibility, usability, and effectiveness of the M4T preK-K program over an eight-week period in 16 preschool centers (N=273; M age=4.22 SD=0.61) that were randomly assigned to the intervention (8 M4T; n=138; M age=4.31 SD=0.61) and the control (8 traditional; n=135; M age=4.13 SD=0.60) group. In both groups, teacher ratings of children's attention, behavioral control, and social skills (i.e., cooperation, assertion, and self-control) in the classroom, as well as children's perceived motor skill competence and executive functions, were collected before and after the intervention. A daily teacher log measured intervention fidelity and perceived experiences with the program. Results showed a significant improvement on attention scores for children in the M4T preK-K group, compared to the control group. No significant differences emerged for behavioral control, social skills, executive functions, and perceived motor competence among groups. A significant time effect was evident for executive functions, with both groups improving over time. Further, the program was well-received, easy to implement in the preschool classroom and with high rates of satisfaction for both children and teachers. The M4T preK-K program is promising in helping teachers prepare preschool children for future educational success.

Associations between Parent-Child Nature Visits and Sleep, Physical Activity and Weight Status among Finnish 3-6-Year-Olds

Nature visits and nature exposure have been shown to be favorably associated with children's health and development, but the research regarding their associations with children's lifestyle habits is limited. The current study aimed to investigate the associations between the frequency of parent-child nature visits and sleep, moderate-to-vigorous physical activity (MVPA) and weight status among three- to six-year-old Finnish preschoolers. Parents and their children (n = 864) participated in a cross-sectional DAGIS (increased health and wellbeing in preschools) study, which was conducted between 2015 and 2016 in Finland. In total, 798 parents answered a questionnaire on the frequency of parent-child nature visits, which also included questions on sociodemographic factors and their children's sleep habits. Parents also reported children's bedtimes and wake-up times and children wore an accelerometer for seven days. Trained researchers measured children's weight and height. Linear and logistic regression analyses were conducted. More frequent parent-child nature visits were associated with children's longer sleep duration at night, higher amounts of MVPA outside preschool time and, among girls, good sleep consistency. The frequency of parent-child nature visits was not significantly associated with whether children were overweight or obese or not. Promoting parent-child nature visits could be a cost-effective way to increase young children's MVPA and enhance night-time sleep.

The Impact of COVID-19 on Preschool-Aged Children's Movement Behaviors in Hong Kong: A Longitudinal Analysis of Accelerometer-Measured Data

During the COVID-19 pandemic, many preschool-aged children were forced to remain indoors due to social distancing measures and school closures. In this study, we examined how children’s movement behaviors (sedentary behaviors, physical activity, and sleep) were affected by the pandemic. Children’s (N = 25, age = 4.4 years, SD = 0.3) movement behaviors were measured before and after the COVID outbreak, respectively. Data collected using accelerometers were analyzed using compositional data analyses. A significant change in the overall time-use composition (F = 5.89, p = 0.002) was found. Results suggested that children spent more time sleeping (8% increase) and in moderate-to-vigorous physical activity (16% increase), with less time spent in sedentary behaviors (9% decrease). However, parent reports suggested that children were less active and had more screen time. In conclusion, the current evidence suggests that children’s physical activity is not negatively impacted by the pandemic. However, the continuous surveillance of movement behaviors of young children during the pandemic is needed.

A systematic review of the validity, reliability, and feasibility of measurement tools used to assess the physical activity and sedentary behaviour of pre-school aged children

Physical activity (PA) and sedentary behaviour (SB) of pre-school aged children are associated with important health and developmental outcomes. Accurate measurement of these behaviours in young children is critical for research and practice in this area. The aim of this review was to examine the validity, reliability, and feasibility of measurement tools used to assess PA and SB of pre-school aged children.Searches of electronic databases, and manual searching, were conducted to identify articles that examined the measurement properties (validity, reliability or feasibility) of measurement tools used to examine PA and/or SB of pre-school aged children (3-7 years old). Following screening, data were extracted and risk of bias assessment completed on all included articles.A total of 69 articles, describing 75 individual studies were included. Studies assessed measurement tools for PA (n = 27), SB (n = 5), and both PA and SB (n = 43). Outcome measures of PA and SB differed between studies (e.g. moderate to vigorous activity, step count, posture allocation). Most studies examined the measurement properties of one measurement tool only (n = 65). Measurement tools examined included: calorimetry, direct observation, combined heart rate and accelerometry, heart rate monitors, accelerometers, pedometers, and proxy report (parent, carer or teacher reported) measures (questionnaires or diaries). Studies most frequently assessed the validity (criterion and convergent) (n = 65), face and content validity (n = 2), test-retest reliability (n = 10) and intra-instrument reliability (n = 1) of the measurement tools. Feasibility data was abstracted from 41 studies.Multiple measurement tools used to measure PA and SB in pre-school aged children showed some degree of validity, reliability and feasibility, but often for different purposes. Accelerometers, including the Actigraph (in particular GT3X versions), Actical, ActivPAL and Fitbit (Flex and Zip), and proxy reported measurement tools used in combination may be useful for a range of outcome measures, to measure intensity alongside contextual information.

Movement behaviors in short versus adequate nocturnal sleepers: A compositional analysis of preschoolers

BACKGROUND

Accruing adequate daily amounts of time spent on movement behaviors (physical activity (PA), sedentary behavior (SB), and sleep) in childhood has been associated with positive short and long-term health outcomes. Nonetheless, how waking time is distributed across PA and SB among preschoolers who are short and adequate sleepers at night is unknown.

AIM

This study investigated: (1) if there are differences in a movement behaviors composition among adequate and short nocturnal sleepers; and (2) the association between preschoolers' time spent in PA, SB, and sleep among adequate and short nocturnal sleepers.

METHODS

A total of 270 preschoolers (132 boys; 3.97 ± 0.81 years old; 15.48 ± 1.62 kg/m² ) participated in this study. PA and SB were assessed using accelerometry (model wGT3X). Sleep duration was assessed through a parental-proxy interview, and preschoolers were stratified as short and adequate sleepers, according to attendance to international sleep duration guidelines. Compositional data analysis was used to explore the time-use patterns of behaviors among adequate and short sleepers.

RESULTS

Short sleepers spent 64 min less time asleep, accumulated 32 min in more sedentary time (p = .005, Cohen's d = 0.36, Bayes Factor: 6.17), and 24 min more in light PA (p = .0005, Cohen's d = 0.44, Bayes Factor: 46.37) compared to adequate sleepers.

CONCLUSIONS

Being a short sleeper was associated with greater time spent in SB and light PA during their waking hours. The health implications of movement behaviors composition among short sleep preschoolers should be further investigated.

A Contactless Method for Measuring Full-Day, Naturalistic Motor Behavior Using Wearable Inertial Sensors

How can researchers best measure infants' motor experiences in the home? Body position-whether infants are held, supine, prone, sitting, or upright-is an important developmental experience. However, the standard way of measuring infant body position, video recording by an experimenter in the home, can only capture short instances, may bias measurements, and conflicts with physical distancing guidelines resulting from the COVID-19 pandemic. Here, we introduce and validate an alternative method that uses machine learning algorithms to classify infants' body position from a set of wearable inertial sensors. A laboratory study of 15 infants demonstrated that the method was sufficiently accurate to measure individual differences in the time that infants spent in each body position. Two case studies showed the feasibility of applying this method to testing infants in the home using a contactless equipment drop-off procedure.

Inactive Lifestyles among Young Children with Innocent Murmurs or Congenital Heart Disease Regardless of Disease Severity or Treatment

BACKGROUND

Sedentary lifestyle morbidities are common among children with congenital heart disease (CHD). Understanding the physical activity trajectory from early childhood could enhance intervention timing/effectiveness.

METHODS

154 children (56% male) were recruited at 12-47 months of age for this prospective, longitudinal, observational study. Physical activity and sedentary behaviour (7-day accelerometry) and motor skill (Peabody Developmental Motor Scales-2) were assessed every 8 months until 5 years of age and then annually. Mixed effect repeated measures regression models described outcome trajectories across study assessments.

RESULTS

Children had an innocent heart murmur (n=28), CHD with insignificant hemodynamics not requiring treatment (n=47), CHD treated by catheterization or surgery without cardiopulmonary bypass (n=31), or CHD treated surgically with bypass (n=48). Motor skill was age appropriate (Peabody 49.0±8.4) but participants had lower physical activity (143±41 mins/day) and higher sedentary time (598±89 mins/day) than healthy peers, starting at 18 months of age. Movement behaviours were not related to treatment group (p>0.10), and physical activity was below the recommended 180 mins/day. Over time, physical activity, sedentary time and motor skill were primarily related to the baseline measure of each outcome (p<0.001).

CONCLUSIONS

Children with simple or complex CHD or innocent heart murmurs have an increased risk for sedentary lifestyles. Their physical activity and sedentary behaviours are established prior to 2 years of age, persist until school age, and are unrelated to motor skill. These results emphasize the need for interventions targeting the youngest children seen in a cardiac clinic, regardless of CHD diagnosis or innocent murmur.

International study of 24-h movement behaviors of early years (SUNRISE): a pilot study from Bangladesh

BACKGROUND

The World Health Organization (WHO) released guidelines for physical activity, sedentary behavior, and sleep for children under 5 years of age in 2019. In response to these guidelines, this pilot study aimed to (i) determine the proportion of preschool children (ages 3-4 years) who met the WHO guidelines; (ii) examine the feasibility of the proposed protocol for the SUNRISE study; and (iii) assess the impact of the COVID-19 pandemic on movement behaviors of preschool children in Bangladesh.

METHODS

Time spent in physical activity, sedentary behavior and sleep were objectively measured using two types of accelerometers (ActiGraph wGT3x-BT and ActivPAL4). Screen time and sleep quality were assessed via parent questionnaire. Fine and gross motor skills were measured using the Ages and Stages Questionnaire (3rd edition). Three executive functions were assessed using the Early Years Toolbox. Focus groups were conducted with parents and childcare staff to determine the feasibility of the protocol. Follow-up data during COVID-19 pandemic was collected from parents over phone.

RESULTS

Data from 63 preschool-aged children and their parents was analyzed in this pilot study. Only three children (4.7%) met all components of the WHO guidelines. Separately, children meeting physical activity, sedentary screen time and sleep guidelines were 71.9%, 17.5%, and 59.7% respectively. The proportion of all children who were developmentally on-track for the gross and fine motor skills was 58.7% and 50.8%, respectively. Parents and educators reported that the protocol was feasible except for the activPAL-4 accelerometer. Approximately, 39% of children (14 out of 37) who wore this device developed itchy skin and rashes resulting in the suspension of using this device mid-way through data collection. During COVID-19, there was a significant decrease in children's total physical activity (- 193 min/day), and time spent outside on weekdays (- 75 min/day) and weekend days (- 131 min/day) and a significant increase in sedentary screen time (+85 min/day).

CONCLUSION

Only a low proportion of children met the WHO guidelines. Methods and devices (except ActivPAL4) used in this pilot study proved to be feasible and this has paved the way to conduct the main SUNRISE study in Bangladesh. Future measures should be taken to address the issue of movement behaviors of children during the time of pandemics like COVID-19.

Objective Measurement of 24-Hour Movement Behaviors in Preschool Children Using Wrist-Worn and Thigh-Worn Accelerometers

In recent years, more attention has been paid towards the study of 24-h movement behaviors (including physical activity (PA), sedentary behavior (SB) and sleep) in preschoolers instead of studying these behaviors in isolation. This study aimed to evaluate the feasibility of using wrist- vs. thigh-worn accelerometers and to report accelerometer-derived metrics of 24-h movement behaviors in preschoolers. A convenience sample of 16 preschoolers (50.0% boys, 4.35 years) and one of their parents were recruited for this study. Preschoolers had to wear the ActivPAL accelerometer (attached to the upper thigh) and Axivity accelerometer (using a wrist band) simultaneously for 7 consecutive days and for 24 h a day. Parents completed an acceptability survey. In total, 16 preschoolers (100.0%) had a minimum of 6 days of valid wrist-worn data, while only 10 preschoolers (62.5%) had a minimum of 6 days of valid thigh-worn data (p = 0.002). When looking at the acceptability, 81.3% of parents indicated that it was easy for their child to wear the Axivity for 7 consecutive days, and 93.8% of parents indicated so for the ActivPAL (p = 0.88). However, some parents stated that the wristband of the Axivity accelerometer was big, which might have affected data collection. Significant differences were found for the measurement of total volume of PA, SB and sleep across 24 h. Total PA was 464.44 min/day (±64.00) with the ActivPAL compared with 354.94 min/day (±57.46) with the Axivity (p < 0.001). The volume of SB was 290.94 min/day (±55.05) with the ActivPAL compared with 440.50 min/day (±50.01) with the Axivity (p < 0.001). The total volume of sleep was also significantly different between both devices (p = 0.001; ActivPAL: 684.63 min/day ± 51.96; Axivity: 645.69 min/day ± 46.78). Overall, parents perceived both devices to be feasible to use for preschoolers. However, future studies are required to validate both devices for the measurement of preschoolers' 24-h movement behaviors since significant differences in the classification of PA, SB and sleep were found in this small sample.

Associations between Movement Behaviours and Obesity Markers among Preschoolers Compliant and Non-Compliant with Sleep Duration: A Latent Profile Analysis

This study identifies physical activity (PA) and sedentary behaviour (SB) clusters in preschoolers compliant (C) or non-compliant (NC) with sleep recommendations; and associates these clusters with obesity markers. PA and SB were objectively assessed (Actigraph WGT3-X) in 272 preschoolers (4.4 ± 0.7 years old). Sleep duration was parent-reported, and preschoolers were classified as C (3-4 years old: 600-780 min/day; 5 years old: 540-660 min/day) or NC with sleep recommendations. Body mass index (BMI) and waist circumference (WC) were assessed according to international protocols. Moderate to vigorous physical activity (MVPA) and light physical activity (LPA) were categorized as low/high (<60 min/>60 min/day or <180 min/180 min/day, respectively). SB was defined according to mean values between clusters. Latent profile analysis was performed. Associations between the observed clusters and obesity markers were determined using linear regression (RStudio; 1.3.1073). Four cluster solutions for C and NC preschoolers were identified. A negative association between C/Low MVPA cluster and BMI, and a positive association between NC/Low MVPA and BMI (β = -0.8, 95%CI = -1.6;-0.1, and β = 0.9, 95%CI = 0.1;1.7, respectively) were observed. No association was seen for SB clusters. Adequate sleep duration may have a protective role for preschoolers' BMI, even if the children do not comply with MVPA recommendations.

The Importance of Parents' Income and Education Level in Relation to Their Preschool Children's Activity Level at Leisure

Previous research indicate that socioeconomic status positively corresponds with adults’ and adolescents’ physical activity levels. This study investigated the relationship between parents’ education and income, and preschool children’s physical activity level. A total of 244 Norwegian preschool children aged four to six and their parents were enrolled in the study. The children wore an Actigraph GT1M accelerometer for seven consecutive days to measure their physical activity level. Parents completed a questionnaire that provided information about their education level and income level. To examine the relationship between the parents’ education and income and their children’s physical activity level at leisure, the Kruskal-Wallis H test was conducted. The results revealed that neither mothers’ nor fathers’ education level or income, were associated with their children’s minutes in moderate to vigorous physical activity (MVPA) at leisure. The preschool curriculum of Norway may be one explanation why socioeconomic status was not linked to physical activity in this study. Another possibility is that this study was limited to full-time students with two parents. More research is needed to determine whether parent income or education is linked to physical activity among more diverse or older children in Norway.

Compliance with the 24-Hour Movement Behavior Guidelines and Associations with Adiposity in European Preschoolers: Results from the ToyBox-Study

In 2019, the World Health Organization (WHO) published 24 h movement behavior guidelines for preschoolers with recommendations for physical activity (PA), screen time (ST), and sleep. The present study investigated the proportion of preschoolers complying with these guidelines (on a total week, weekdays and weekend days), and the associations with adiposity. This cross-sectional study included 2468 preschoolers (mean age: 4.75 years; 41.9% boys) from six European countries. The associations were investigated in the total sample and in girls and boys separately. PA was objectively assessed by step counts/day. Parent-reported questionnaires provided ST and sleep duration data. Generalized estimating equations were used to analyze the association between guideline compliance and adiposity indicators, i.e., body mass index (BMI) z-score and waist to height ratio (WHR). Only 10.1% of the preschoolers complied with the 24 h movement behavior guidelines, 69.2% with the sleep duration guideline, 39.8% with the ST guideline and 32.7% with the PA guideline. No association was found between guideline compliance with all three movement behaviors and adiposity. However, associations were found for isolated weekday screen time (BMI z-scores and WHR: p = 0.04) and weekend day sleep duration (BMI z-scores and WHR: p = 0.03) guideline compliance with both lower adiposity indicators. The latter association for sleep duration was also found in girls separately (BMI z-scores: p = 0.02; WHR: p = 0.03), but not in boys. Longitudinal studies, including intervention studies, are needed to increase preschoolers’ guideline compliance and to gain more insight into the manifestation of adiposity in children and its association with 24 h movement behaviors from a young age onwards.

Exploring Preschoolers' Physical Activity and Sedentary Time During Outdoor Play at Childcare: A Cross-Sectional Analysis of the Supporting Physical Activity in the Childcare Environment Study

BACKGROUND

Moderate-to-vigorous physical activity (MVPA) offers many health benefits for preschoolers (2.5-5 y). In childcare, MVPA is predominantly accumulated outdoors, with higher rates purported among children within the first few minutes outside. The Supporting Physical Activity in the Childcare Environment intervention included shorter, more frequent outdoor play sessions; this study sought to explore children's activity levels during various outdoor play schedules.

METHODS

During the final week of the Supporting Physical Activity in the Childcare Environment intervention, preschoolers wore an Actical™ accelerometer for 5 days during childcare and staff logged outdoor times. Separate linear mixed effects models were run to explore the effect of the intervention on preschoolers' physical activity (total and MVPA) and sedentary time during outdoor play. Sex was entered as an interaction effect.

RESULTS

Preschoolers (n = 292) were significantly more active in the first 10 minutes outdoors compared with remaining time (P < .0083). For total outdoor time, children in the experimental group engaged in significantly less sedentary time than those in the control group (P < .017), and experimental group boys and girls engaged in higher MVPA than boys and girls in the control group (P < .017).

CONCLUSIONS

Findings support scheduling more frequent outdoor play sessions in childcare to increase physical activity participation among young children.

School-Time Movement Behaviors and Fundamental Movement Skills in Preschoolers: An Isotemporal Reallocation Analysis

Little is known of how reallocations of time spent in different movement behaviors during preschool might relate to preschoolers' fundamental movement skills (FMS), a key predictor of later physical activity (PA). Thus, the aim of this study was to examine (a) whether preschoolers' school-time movement was associated with their FMS and (b) the effects on FMS of reallocating time between PA and sedentary behavior (SB). This was a cross-sectional study, using intervention data with Brazilian low-income preschoolers. We observed Brazilian preschoolers of both sexes (M_age = 4.5, SD = 0.8 years-old; 101boys) over 10 hours of school-time and objectively assessed their PA and SB with Actigraph wGT3X and their FMS with the Test of Gross Motor Development - Second Edition. We explored the associations between school-time movement behaviors and FMS and between reallocated school-time movement behaviors and FES using compositional analysis in R (version 1.40-1), robCompositions (version 0.92-7), and lmtest (version 0.9-35) packages. This isotemporal reallocation showed that, for manipulative skills, reallocating time (5, 10, and 15 minutes, respectively) from light PA to SB was associated with increasing skill (0.14, 0.28, and 0.42 FMS units), raising questions as to whether fine motor activity occurred during SB. Thus, school-time movement significantly predicted FMS, with a modest increase in SB, at the expense of light PA eliciting improved manipulative skills.

Teaching Methodologies and School Organization in Early Childhood Education and Its Association with Physical Activity

Early childhood represents a crucial period for child development. Physical activity is essential in this process, but studies show that children are very inactive and do not meet the recommended minimums. Due to the large proportion of time they spend at school, it is necessary to examine active and sedentary behaviors in these environments. The aim of the study is to analyze the amount and intensity of physical activity in preschool children during the school day according to the methodology used. Using accelerometry, the amount and intensity of physical activity and sedentary behavior of 156 children aged 4-6 years at different times of the school day were evaluated. The results revealed that preschoolers spend most of their class time sedentary, with children participating in active methodologies registering the highest amount and intensity of physical activity. Recess and specific motor sessions are the most active times, although the latter should increase the time of intense activity that they imply. To increase physical activity during the school day, it is necessary to establish movement integration methodologies, while increasing the number and adjusting the duration of specific motor sessions and of recesses, so that the maximum possible use is made of them.

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.

Temperament, physical activity and sedentary time in preschoolers - the DAGIS study

Background

Identifying individual characteristics linked with physical activity (PA) and sedentary time (SED) can assist in designing health-enhancing interventions for children. We examined cross-sectional associations of temperament characteristics with 1) PA and SED and 2) meeting the PA recommendation in Finnish children.

Methods

Altogether, 697 children (age: 4.7 ± 0.9 years, 51.6% boys) within the Increased Health and Wellbeing in Preschools (DAGIS) study were included. Parents responded to the Very Short Form of the Children’s Behavior Questionnaire consisting of three temperament dimensions: surgency, negative affectivity, and effortful control. PA and SED were assessed for 7 days (24 h per day) using a hip-worn ActiGraph accelerometer, and the daily minutes spent in light PA (LPA), moderate PA (MPA), vigorous PA (VPA), and SED were calculated. The PA recommendation was defined as having PA at least 180 min/day, of which at least 60 min/day was in moderate-to-vigorous PA. Adjusted linear and logistic regression analyses were applied.

Results

Surgency was associated with LPA (B = 3.80, p = 0.004), MPA (B = 4.87, p < 0.001), VPA (B = 2.91, p < 0.001), SED (B = − 11.45, p < 0.001), and higher odds of meeting the PA recommendation (OR = 1.56, p < 0.001). Effortful control was associated with MPA (B = − 3.63, p < 0.001), VPA (B = − 2.50, p < 0.001), SED (B = 8.66, p < 0.001), and lower odds of meeting the PA recommendation (OR = 0.61, p = 0.004). Negative affectivity was not associated with PA, SED, or meeting the PA recommendation.

Conclusion

Children’s temperament should be considered when promoting PA in preschoolers. Special attention should be paid to children scoring high in the temperament dimension effortful control.

Three-Year Changes in Low-Income Children's Physical Activity: Prospective Influence of Neighborhood Environment and Parent Supportive Behavior

Objectives

To prospectively evaluate parent supportive behaviors (PSB) for child physical activity (PA) and neighborhood environment variables on changes in child PA over 3 years.

Study design

Secondary data analysis of the Now Everybody Together for Amazing and Healthful Kids-Works study with 534 parent-child (age 2-4 years) dyads randomized to a community-based pediatric obesity prevention intervention for 3 years (92% retention). PSB and neighborhood environmental variables were examined in relation to changes in child moderate-to-vigorous PA (MVPA), light and sedentary activity, and screen time. Child and parent accelerometry data were collected at visit 0, 12, 24, and 36 months. Mixed multivariate models were used to examine independent and interactive effects of parent-level and neighborhood-level variables on changes in child PA outcomes.

Results

PSB significantly interacted with visit on change in child MVPA (β = 0.12) and sedentary behaviors (β = -0.18). Over 3 years, a 1-unit increase in PSB was associated with an average increase of 4.3 minutes/day of MVPA and an average decrease of 6.5 minutes/day of sedentary time. Significant main effects were observed for PSB and 3-year change in child screen time (β = -0.05). The children of parents with higher PSB at baseline watched an average of 1.8 fewer minutes/day of screen time compared with parents with lower baseline PSB. Neighborhood-level variables were not significantly associated with changes in child PA outcomes.

Conclusions

Parents who increase their supportive behaviors for their child's PA have children who are more physically active and less sedentary over time. Interventions to increase preschool-age children's PA may enhance their effectiveness by targeting parents' supportive behaviors for their child's PA.

Y-PATHS: A Conceptual Framework for Classifying the Timing, How, and Setting of Youth Physical Activity

BACKGROUND

Multiple models and frameworks exist for the measurement and classification of physical activity in adults that are applied broadly across populations but have limitations when applied to youth. The authors propose a conceptual framework specifically designed for classifying youth physical activity.

METHODS

The Youth Physical Activity Timing, How, and Setting (Y-PATHS) framework is a conceptualization of the when (timing), how, and where (setting) of children's and adolescents' physical activity patterns. The authors developed Y-PATHS using the design thinking process, which includes 3 stages: inspiration, ideation, and implementation.

RESULTS

The Y-PATHS includes 3 major components (timing, how, and setting) and 13 subcomponents. Timing subcomponents include (1) school days: in-school, (2) school days: out-of-school, and (3) nonschool days. How subcomponents include: (1) functional, (2) transportation, (3) organized, and (4) free play. Setting subcomponents include: (1) natural areas, (2) schools, (3) home, (4) recreational facilities, (5) shops and services, and (6) travel infrastructure.

CONCLUSIONS

The Y-PATHS is a comprehensive classification framework that can help researchers, practitioners, and policymakers to better understand youth physical activity. Specifically, Y-PATHS can help to identify the domains of youth physical activity for surveillance and research and to inform the planning/evaluation of more comprehensive physical activity programming.

The relationship between educators' and children's physical activity and sedentary behaviour in early childhood education and care

OBJECTIVES

The early childhood education and care (ECEC) environment has a significant role to play in the promotion of physical activity and reduction of sedentary behaviour in young children. Educators may be an important social factor influencing children's physical activity and sedentary behaviour, however limited evidence exists on this relationship. The primary aim was to examine the relationships between educators' and children's physical activity and sedentary behaviours within ECEC settings.

DESIGN

A cross sectional study.

METHODS

The study involved 11 ECEC centres from NSW, Australia (n=110 educators; n=490 children). Data for each centre were collected over five consecutive days. Objectively measured physical activity and sedentary behaviour were collected from children using Actigraph accelerometers and were analysed using STATA 13c. Linear regression was used to examine relationships between children and educators, adjusted for centre clustering.

RESULTS

A significant association was reported between educators' sedentary behaviour and children's sedentary behaviour (p=0.047). Educators spent 61% of their work day in sedentary behaviour. No significant associations were reported between educators' physical activity and children's physical activity, for any intensity of physical activity.

CONCLUSIONS

The positive relationship between educators' sedentary behaviours and children's sedentary behaviour in this study highlights a novel area to target in future interventions. Improving physical activity and sedentary behaviours of educators will likely improve children's physical activity levels and thus health and wellbeing outcomes.

Effects of a teacher training program to promote physically active play among preschoolers with autism spectrum disorders

Wellness Enhancing Physical Activity for Young Children (WE PLAY) is an intervention intended to promote physical activity (PA) among typically-developing preschool children in child care settings. It was adapted for use by teachers who educate children with Autism Spectrum Disorders (ASD). This study used a multiple baseline design across participants to evaluate the impact of WE PLAY-Autism on teachers' PA facilitating behaviors and on the PA levels of children with ASD. Visual analysis and effect size estimates indicated that two of the three teachers increased their PA facilitating behavior, although this was insufficient to demonstrate a functional relation. Children's (n = 5) PA was measured daily during school hours using accelerometry. Visual analysis, which was further supported by effect size calculations, indicated higher average levels of moderate-to-vigorous PA (MVPA) among preschoolers with ASD in the intervention phase (Tau-U_{A vs. B} = 0.53, p < .001, Hedges' g = 0.99, 95% CI [0.56, 1.43]) and post-training phase (Tau-U_{A vs. B} = 0.55, p < .001, Hedges' g = 1.17, 95% CI [0.73, 1.60]) in comparison to the baseline phase. WE PLAY-Autism is an intervention deserving of further investigation given its meaningful impact on the MVPA of preschoolers with ASD paired with its potential for broad implementation in preschools.

Association between Physical Activity and Fundamental Movement Skills in Preschool-Aged Children: Does Perceived Movement Skill Competence Mediate This Relationship?

Objectives: The purpose of this research is to examine whether perceived fundamental movement skills (FMS) competence mediated the relationship between actual FMS and physical activity (PA) in Hong Kong preschool-aged children. Design: A cross−sectional study. Methods: 148 preschool-aged children (43% girls; mean age = 4.52 ± 0.67 years) from five preschools/childcare centres completed all assessments. Actual FMS was rated using the Test of Gross Motor Development−2, whilst perceived FMS was assessed via the Pictorial Scale for Perceived Movement Skill Competence. PA was measured through accelerometry. A bootstrap method was used to assess the potential mediating effect of perceived movement skill competence on the relationship between actual FMS and PA. All mediation models were adjusted for sex and age. Results: Mediation analyses showed that the direct path between actual FMS and moderate-to-vigorous physical activity (MVPA) was significant (b = 0.228, p = 0.008), as was the path between MVPA and actual FMS (b = 0.214, p = 0.008). However, perceived FMS competence did not mediate the association between actual FMS and MVPA in the models. Conclusions: Our results showed evidence of reciprocal pathways between actual FMS and MVPA, reinforcing the need to simultaneously target both domains as part of broader developmental strategies, initiated in early childhood. Unlike emergent adolescence, perceptions of movement skill competence do not play a significant role in influencing the relationship between actual FMS proficiency and MVPA in this developmental period.

Spontaneous movements in the newborns: a tool of quantitative video analysis of preterm babies

BACKGROUND AND OBJECTIVES

The number of preterm babies is steadily growing world-wide and these neonates are at risk of neuro-motor-cognitive deficits. The observation of spontaneous movements in the first three months of age is known to predict such risk. However, the analysis by specifically trained physiotherapists is not suited for the clinical routine, motivating the development of simple computerized video analysis systems, integrated with a well-structured Biobank to make available for preterm babies a growing service with diagnostic, prognostic and epidemiological purposes.

METHODS

MIMAS (Markerless Infant Movement Analysis System) is a simple, low-cost system of video analysis of spontaneous movements of newborns in their natural environment, based on a single standard RGB camera, without markers attached to the body. The original videos are transformed into binarized sequences highlighting the silhouette of the baby, in order to minimize the illumination effects and increase the robustness of the analysis; such sequences are then coded by a large set of parameters (39) related to the spatial and spectral changes of the silhouette. The parameter vectors of each baby were stored in the Biobank together with related clinical information.

RESULTS

The preliminary test of the system was carried out at the Gaslini Pediatric Hospital in Genoa, where 46 preterm (PT) and 21 full-term (FT) babies (as controls) were recorded at birth (T0) and 8-12 weeks thereafter (T1). A simple statistical analysis of the data showed that the coded parameters are sensitive to the degree of maturation of the newborns (comparing T0 with T1, for both PT and FT babies), and to the conditions at birth (PT vs. FT at T0), whereas this difference tends to vanish at T1. Moreover, the coding method seems also able to detect the few 'abnormal' preterm babies in the PT populations that were analyzed as specific case studies.

CONCLUSIONS

Preliminary results motivate the adoption of this tool in clinical practice allowing for a systematic accumulation of cases in the Biobank, thus for improving the accuracy of data analysis performed by MIMAS and ultimately allowing the adoption of data mining techniques.

Objective Measurement of Physical Activity Attributed to a Park-Based Afterschool Program

BACKGROUND

Only 24% of US youth meet physical activity recommendations set by the Centers for Disease Control and Prevention. Research demonstrates that community-based programs provide underresourced minority youth with opportunities for routine physical activity, although limited work draws from accelerometry data. This study objectively assessed youth physical activity attributable to participation (vs nonparticipation) days in a park-based afterschool program in Miami-Dade County, Miami, FL.

METHODS

Participants' (n = 66; 60% male; 57% white Hispanic, 25% non-Hispanic black, 14% Black Hispanic, mean age = 10.2 y) physical activity was assessed April to May 2019 over 10 days across 7 park sites using Fitbit (Charge 2) devices. Separate repeated-measures multilevel models were developed to assess the relationship between program daily attendance and total (1) moderate to vigorous physical activity minutes and (2) step counts per day.

RESULTS

Models adjusted for individual-level age, sex, race/ethnicity, poverty, and clustering by park showed significantly higher moderate to vigorous physical activity minutes (β = 25.33 more minutes per day; 95% confidence interval, 7.0 to 43.7, P < .01) and step counts (β = 4067.8 more steps per day; 95% confidence interval, 3171.8 to 4963.8, P < .001) on days when youth did versus did not attend the program.

CONCLUSIONS

Study findings suggest that park-based programs may support underserved youth in achieving daily physical activity recommendations.

Validation of the Physical Activity Questions in the World Health Organization Health Behavior in School-Aged Children Survey Using Accelerometer Data in Japanese Children and Adolescents

BACKGROUND

An international physical activity (PA) questionnaire is beneficial to make cross-country comparisons among children and adolescents. This study assesses the validity of the PA questions in the World Health Organization Health Behavior in School-Aged Children (WHO HBSC) survey in Japanese children and adolescents.

METHODS

Participants were fifth- to sixth-grade Japanese primary school students (67 students aged 10.8 [0.5] y) and first- to third-grade junior high school students (108 students aged 13.0 [0.7] y). The Japanese version of the PA questions in the WHO HBSC (WHO HBSC-J) was used. To assess the validity of the PA questions, the authors used a partial correlation adjusted for sex, age, and relative weight between the answers to the survey questions and objectively measured moderate to vigorous PA (MVPA) by an accelerometer.

RESULTS

A significant positive correlation was found between accelerometer-measured MVPA and the number of reported days with at least 60 minutes/day of MVPA in primary school students (r = .39, P = .002) and junior high school students (r = .32, P < .001).

CONCLUSION

The HBSC-J has moderate validity for evaluating MVPA in Japanese primary school and junior high school students.

Machine learning sleep duration classification in Preschoolers using waist-worn ActiGraphs

OBJECTIVE

To create a sleep duration classification technique for waist-worn ActiGraph accelerometers in preschool-aged children.

METHODS

Children wore ActiGraph wGT3X-BT accelerometers on their right hip for 7 days (24 h/day). Ground truth nap, sleep, and wake were estimated through visual inspection of accelerometer data, guided by sleep log-sheets and previously published visual inspection heuristics. Raw accelerometer data (30Hz) were used to generate 144 features aggregated to 1-min epochs. Machine learning classification (ie, Random Forest and Hidden Markov Modeling [HMM]) predicted nap, sleep, and wake. A simplified prediction formula was also created using features (n = 10) with the highest mean decrease in Gini index during training of Random Forests, and temporally smoothed with rolling median calculations.

RESULTS

Children (n = 89, mean age = 4.5 years, 67% boys) contributed >600,000 min of accelerometer data. Overall classification accuracy of the Random Forest and HMM classifier was 96.2% (95%CI: 96.1, 96.2%), with a Kappa score of 0.93. Additionally, overall classification accuracy for the temporally smoothed simplified formula was 93.7% (95%CI: 93.6, 93.7%) with Kappa = 0.87. Nap prediction accuracy was 99.8% for the final machine learning model, and 86.1% for the simplified formula. For participant-level daily summaries, generally small but statistically significant differences were found between machine learning and ground truth behaviour predictions, whereas non-significant differences were found between the simplified formulas and ground truth predictions.

CONCLUSIONS

Predictions for both machine learning and the simplified formula had almost perfect agreement with visual inspection ground truth measurements. Future research is needed to confirm these findings using polysomnography ground truth sleep measurements.

Free-living Evaluation of Laboratory-based Activity Classifiers in Preschoolers

Machine learning classification models for accelerometer data are potentially more accurate methods to measure physical activity in young children than traditional cut point methods. However, existing algorithms have been trained on laboratory-based activity trials, and their performance has not been investigated under free-living conditions.

PURPOSE

This study aimed to evaluate the accuracy of laboratory-trained hip and wrist random forest and support vector machine classifiers for the automatic recognition of five activity classes: sedentary (SED), light-intensity activities and games (LIGHT_AG), walking (WALK), running (RUN), and moderate to vigorous activities and games (MV_AG) in preschool-age children under free-living conditions.

METHODS

Thirty-one children (4.0 ± 0.9 yr) were video recorded during a 20-min free-living play session while wearing an ActiGraph GT3X+ on their right hip and nondominant wrist. Direct observation was used to continuously code ground truth activity class and specific activity types occurring within each class using a bespoke two-stage coding scheme. Performance was assessed by calculating overall classification accuracy and extended confusion matrices summarizing class-level accuracy and the frequency of specific activities observed within each class.

RESULTS

Accuracy values for the hip and wrist random forest algorithms were 69.4% and 59.1%, respectively. Accuracy values for hip and wrist support vector machine algorithms were 66.4% and 59.3%, respectively. Compared with the laboratory cross validation, accuracy decreased by 11%-15% for the hip classifiers and 19%-21% for the wrist classifiers. Classification accuracy values were 72%-78% for SED, 58%-79% for LIGHT_AG, 71%-84% for MV_AG, 9%-15% for WALK, and 66%-75% for RUN.

CONCLUSION

The accuracy of laboratory-based activity classifiers for preschool-age children was attenuated when tested on new data collected under free-living conditions. Future studies should train and test machine learning activity recognition algorithms using accelerometer data collected under free-living conditions.

Accelerometric Assessment of Postural Balance in Children: A Systematic Review

The correct development of postural control in children is fundamental to ensure that they fully reach their psychomotor capacities. However, this capacity is one of the least studied in the clinical and academic scope regarding children. The objective of this study was to analyze the degree of implementation of accelerometry as an evaluation technique for postural control in children and how it is being used.

METHODS

A systematic search was conducted in PubMed, SpringerLink, SportsDiscus, Medline, Scopus, and Web of Science with the following terms: balance, postural control, children, kids, accelerometry, and accelerometer.

RESULTS

The search generated a total of 18 articles. Two groups of studies were differentiated: those which exclusively included healthy individuals (n = 5) and those which included children with pathologies (n = 13). Accelerometry is being used in children mainly to assess the gait and static balance, as well as to identify the differences between healthy children and children with developmental disorders.

CONCLUSIONS

Accelerometry has a discrete degree of implementation as an evaluation tool to assess postural control. It is necessary to define a systematic method for the evaluation of postural control in pediatrics, in order to delve into the development of this capacity and its alterations in different neurodevelopmental disorders.

Adiposity and High Blood Pressure during Childhood: A Prospective Analysis of the Role of Physical Activity Intensity and Sedentary Time in the GECKO Drenthe Cohort

Whereas in adults, physical inactivity is strongly related to obesity and hypertension, in young children the evidence is inconsistent and scarce. We examined the association between physical activity (PA) behaviours at 5-6 years of age and adiposity and blood pressure (BP) at 10-11 years in 947 children (51% boys) from the Groningen Expert Center for Kids with Obesity (GECKO) Drenthe cohort. Sedentary time (ST) and light, moderate, and vigorous PA were assessed using accelerometry (ActiGraph GT3X, wear time > 600 min/day, ≥3 days). Body mass index (BMI), waist circumference (WC), and systolic and diastolic BP were measured at 5-6 and 10-11 years of age and standardized as age- and sex-adjusted (and height-adjusted, for BP) z-scores. Adjusted linear and logistic regression models showed that most PA behaviours were not related to standardized BMI or WC, overweightness/obesity, abdominal overweightness/obesity, standardized systolic or diastolic BP, pulse pressure, or prehypertension at 10-11 years of age. Only if children spent more time in vigorous PA was WC slightly lower (B (95% CI) = -0.08 (-0.16, -0.01) SD, stdβ = -0.068) and the increase in WC over the years was less (B (95% CI) = -0.10 (-0.18, -0.01) SD; stdβ = -0.083). To conclude, at this very young age, PA behaviours are not a strong predictor for overweightness/obesity or hypertension later in childhood.

Association between 24-hour movement guidelines and physical fitness in children

BACKGROUND

Physical fitness levels in Japanese children are lower than those in the 1980s. Twenty-four hour movement guidelines were recently developed to improve both present and future health of children. This study examined whether meeting the 24 h movement guidelines was associated with physical fitness measures in primary school children.

METHODS

Participants were 243 Japanese children (9.4 ± 1.7 years). Moderate-to-vigorous physical activity (MVPA) was evaluated using accelerometry. Sleep duration and screen time were reported. Physical fitness was assessed by grip strength, sit-ups, sitting trunk flexion, and 20 m shuttle run test. Meeting the 24 h movement guidelines was defined as: 9-11 h / night of sleep, ≤2 h/day of screen time, and at least 60 min/day of MVPA. The associations between physical fitness and the recommendations were analyzed using analysis of covariance.

RESULTS

Children meeting the MVPA recommendation alone performed better on the 20 m shuttle run and sit-up test compared to those not meeting the recommendation (number of laps: 41 vs 36, P = 0.009 and number of repetitions: 16.3 vs 14.7, P = 0.021). Children meeting the combination of MVPA and sleep recommendation scored significantly higher on the sit-up test compared to those not meeting the recommendations (number of repetitions: 16.5 vs 15.0, P = 0.038) but the effect was similar to that of the MVPA reference only. Meeting all three 24 h movement guidelines was not associated with measures of fitness in this sample. Meeting the MVPA recommendation was associated with greater aerobic fitness and muscle endurance.

CONCLUSIONS

In order to enhance children's physical fitness, public health recommendations should primarily target MVPA.

Children's physical activity level and sedentary behaviour in Norwegian early childhood education and care: effects of a staff-led cluster-randomised controlled trial

BACKGROUND

A growing body of evidence suggest that the children's physical activity (PA) level in early childhood education and care (ECEC) settings are insufficient. Since most children attend ECEC settings for many hours on most days of the week, and these institutions reach children across the socioeconomic spectrum, the ECEC settings may serve as an ideal avenue for increasing physical activity level, reduce sedentary time and enhance the overall health of young children. This paper investigates the effectiveness of the "Active Kindergarten - Active Children" study to increase children's PA level and reduce sedentary time within the ECEC setting.

METHODS

Accelerometers were used to asses PA and sedentary time. A total of 116 three to four-year olds took part in a randomised controlled trial in 11 ECEC settings. Participants were cluster-randomised, by ECEC setting, to either a 12 week staff-led and expert-supported intervention or a waiting list control group.

RESULTS

The intervention group increased time spent in moderate- and vigorous intensity PA by 10 min/day (95% CI = 3, 18; P = 0.01), took 1909 more steps per day (95% CI = 1130, 2688; P < 0.01) and reduced sedentary time with 14 min/day (95% CI = - 27, - 1; P = 0.04) compared to the control group. The intervention group had a 2.4 higher odds (95% CI = 1.05, 5.7; P = 0.04) of meeting the PA recommendations compared to the control group at follow-up.

CONCLUSIONS

Our results show that a flexible staff-led and expert-supported multicomponent PA intervention can increase total PA level, moderate- and vigorous intensity PA and reduce time spent sedentary in three to four-year old children during their stay in ECEC settings.

TRIAL REGISTRATION

The trial was retrospectively registered on September 19, 2020 and available online at ClinicalTrials.gov: No. NCT04555746 .

Intervention to Improve Preschool Children's Fundamental Motor Skills: Protocol for a Parent-Focused, Mobile App-Based Comparative Effectiveness Trial

Background

Preschool age is an important time to master fundamental motor skills (FMS) through structured physical activity, yet many young children lag behind in motor skill development.

Objective

The Promoting Lifelong Activity in Youth (PLAY) study is a pilot comparative effectiveness trial to test the acceptability, feasibility, and preliminary effectiveness of a mobile app delivered to parents to promote FMS development in their preschool children (aged 3-5 years).

Methods

We conducted a 2-arm, parallel-design, randomized comparative effectiveness trial in 72 parent-child dyads from the southeastern United States. Experts in motor development and developmental psychology developed an app designed to deliver a 12-week program to parents of preschoolers using 1 of 2 curricula: an FMS program (intervention) that involved peer modeling, parent engagement, and structured skills-based activities and an unstructured physical activity (comparator) curriculum that provided suggestions for child-led physical activity (ie, free play). Primary outcomes are feasibility and acceptability of the app and child’s FMS measured at end of intervention (week 12). Exploratory outcomes are child’s objective physical activity, perceived movement competence, and parent report of self-regulation at the end of treatment (week 12) and sustained outcomes at follow-up (week 24).

Results

This project was funded in September 2018, with institutional review board approval in August 2018. Data collection took place from May 2019 through February 2020. To date, the project team has completed data collection on 69 preschool-age children, and results are expected to be published by 2021.

Conclusions

The PLAY study examines the feasibility and preliminary effectiveness of a mobile app, parent-led curricula to promote FMS proficiency for preschool children. If found to be effective, the app has the potential for wide-scale dissemination to parents of preschoolers and to provide a model for the utilization of mobile apps to promote young children’s motor skill development.

Trial Registration

ClinicalTrials.gov NCT03901300; https://clinicaltrials.gov/ct2/show/NCT03901300

International Registered Report Identifier (IRRID)

DERR1-10.2196/19943

Adherence to 24-hour movement guidelines in low-income Brazilian preschoolers and associations with demographic correlates

BACKGROUND

The importance of movement behaviors for health is well known, although few studies have examined the adherence to movement guidelines in low-income preschoolers from a middle-income country, as Brazil. This study reports the proportion of preschoolers meeting the 24-hour movement guidelines and investigates its associations with demographic correlates in Brazilian low-income preschoolers.

METHODS

Two hundred and seventy preschoolers (132 boys, means age = 3.97 ± 0.80) provided physical activity (PA) data (Actigraph wGT3X). Sleep duration, screen time, and social correlates were parent-reported. Preschoolers were classified as compliant/not compliant with the 24-hour movement guidelines. Relationships between compliance with movement behaviors guidelines and demographic correlates were calculated using a network analysis (Mplus 8.0; Rstudio).

RESULTS

Preschoolers were active (273.52 ± 62.08 minutes/day of total PA), though moderate-to-vigorous physical activity (MVPA) time was below the guideline (58.68 ± 22.51 minutes/day); spent more than the recommended 60 minutes/day on screen time (169.91 ± 97.07 minutes/day); and slept less than 10 hours per night (9.44 ± 1.12 hours/day). Only 3% of the sample complied with the guidelines. PA showed the highest compliance (43%), compared to sleep duration (35%) and screen time (15%). Male sex was related to adherence to MVPA recommendations, while female sex, with adherence to total PA recommendations. Child's primary caregiver was the most important centrality indicator in the network.

CONCLUSION

Only 3% of the assessed preschoolers are compliant with the 24-hour movement behaviors guidelines. Strategies to promote adherence to movement behaviors among low-income preschoolers should consider child's primary caregivers to support movement behaviors.

Preschool environment and preschool teacher's physical activity and their association with children's activity levels at preschool

Objective

The aim of this study was to investigate the association between preschool playground size, formalized physical activity (PA) policies, time spent outdoors and preschool teacher’s levels of PA and children’s objectively assessed levels of PA and sedentary time (ST) during preschool hours.

Methods

In total, 369 children and 84 preschool teachers from 27 preschools in Södermalm municipally, Stockholm Sweden wore an Actigraph GT3X+ accelerometer during 7 consecutive days. Preschool environmental and structural characteristics were measured via the Environment and Policy Evaluation Self-Report (EPAO-SR) instrument and time in- and outdoors was recorded by preschool teachers during the PA measurements. Weight and height of children were measured via validated scales and parents filled out a questionnaire on demographical and descriptive variables. Linear mixed models, nested on preschool level, were used to assess the association between predictors and outcomes.

Results

The mean child age was 4.7 years (SD 0.8) and 45% were girls. We found that children were more active in preschools with a formalized PA policy, compared to preschools without such a policy, but not less sedentary. The association between policy and activity seemed to be more pronounced when accounting for other environmental factors. Similar associations were found in children spent most time outdoors (uppermost quartile) compared with children spent least time outdoors (Lowermost quartile). Preschool teachers’ light PA (LPA) (ß = 0.25, P = 0.004) and steps (ß = 0.52, P<0.001) were associated with children’s LPA and steps while the preschool playground size showed no association with PA in children, when accounting for other environmental factors.

Conclusion

The current study showed that preschool structural characteristics such as formalized PA policies and more time spent outdoors were positively associated with children’s PA. These findings suggest that formalized PA policies and time outdoors may be of importance for promoting children’s PA during preschool hours.

How Many Days are Necessary to Represent Typical Daily Leg Movement Behavior for Infants at Risk of Developmental Disabilities?

BACKGROUND

Movement characteristics can differentiate between infants at risk and infants with typical development. However, it is unknown how many days are needed to accurately represent typical daily behavior for infants at risk of developmental disabilities when using wearable sensors. To consider the balance between participant burden and the amount of data collected and optimizing the efficiency of data collection, our study determined (1) how many days were necessary to represent typical movement behavior for infants at risk of developmental disabilities and (2) whether movement behavior was different on weekend days and weekdays.

METHODS

We used Opal wearable sensors to collect at least 5 days of 11 infants' leg movement data. The standard (average of 5 days) was compared with four methods (average of the first 1/2/3/4 days) using the Bland-Altman plots and the Spearman correlation coefficient. We also compared the data from the average of 2 weekend days to the average of the first 2 weekdays for 8 infants.

RESULTS

The Spearman correlation coefficient comparing the average of the first 2 days of data and the standards were all above 0.7. The absolute differences between them were all below 10% of the standards. The Bland-Altman plots showed more than 90% of the data points comparing the average of 2 days and the standards fell into the limit of agreement for each variable. The absolute difference between weekend days and weekdays for the leg movement rate, duration, average acceleration, and peak acceleration was 15.2%, 1.7%, 6.8% and 6.3% of the corresponding standard, respectively.

CONCLUSION

Our results suggest 2 days is the optimal amount of data to represent typical daily leg movement behavior of infants at risk of developmental disabilities while minimizing participant burden. Further, leg movement behavior did not differ distinctly across weekend days and weekdays. These results provide supportive evidence for an efficient amount of data collections when using wearable sensors to evaluate movement behavior in infants at risk of developmental disabilities.

Feasibility of Targeting Hispanic Fathers and Children in an Obesity Intervention: Papás Saludables Niños Saludables

Background: Hispanic children and men carry a high burden for obesity and associated medical conditions. Healthy Dads Healthy Kids was the first obesity prevention intervention targeting fathers and demonstrated weight loss among fathers and behavior change among fathers and children in Australia. The aim of this study was to assess the feasibility of a culturally adapted version of the program for Hispanic families, Papás Saludables Niños Saludables. Methods: A randomized waitlist controlled trial with a process evaluation was conducted to assess the feasibility of Papás Saludables Niños Saludables(NCT03532048). Fathers, their partner (mother), and one to three children were enrolled. A priori feasibility criteria were: (1) recruit 40 Hispanic fathers and their families in ≤4 months; (2) retain 80% of participants for pre- and postassessments; (3) maintain ≥70% attendance to the 10 sessions; (4) obtain 80% "excellent" or "good" satisfaction from participants; and (5) collect anthropometric and behavioral data on ≥75% of participants at baseline and follow-up. Results: The study enrolled 90% (n = 36) of the goal from one local pediatric clinic between May and August 2018; retained 75% of participants for postassessment; maintained 72% attendance among those who started the program; and achieved 100% "excellent/good" satisfaction ratings among the participating fathers and mothers. One hundred percent of participants had most anthropometric and behavioral data at baseline and 72% at follow-up. Conclusions: With oversampling and improvements in the recruitment strategies, Papás Saludables Niños Saludables is feasible for a randomized controlled clinical trial to address whether a father-targeted lifestyle program is efficacious among low-income Hispanic men and their children.

Calibrating Wrist-Worn Accelerometers for Physical Activity Assessment in Preschoolers: Machine Learning Approaches

BACKGROUND

Physical activity (PA) level is associated with multiple health benefits during early childhood. However, inconsistency in the methods for quantification of PA levels among preschoolers remains a problem.

OBJECTIVE

This study aimed to develop PA intensity cut points for wrist-worn accelerometers by using machine learning (ML) approaches to assess PA in preschoolers.

METHODS

Wrist- and hip-derived acceleration data were collected simultaneously from 34 preschoolers on 3 consecutive preschool days. Two supervised ML models, receiver operating characteristic curve (ROC) and ordinal logistic regression (OLR), and one unsupervised ML model, k-means cluster analysis, were applied to establish wrist-worn accelerometer vector magnitude (VM) cut points to classify accelerometer counts into sedentary behavior, light PA (LPA), moderate PA (MPA), and vigorous PA (VPA). Physical activity intensity levels identified by hip-worn accelerometer VM cut points were used as reference to train the supervised ML models. Vector magnitude counts were classified by intensity based on three newly established wrist methods and the hip reference to examine classification accuracy. Daily estimates of PA were compared to the hip-reference criterion.

RESULTS

In total, 3600 epochs with matched hip- and wrist-worn accelerometer VM counts were analyzed. All ML approaches performed differently on developing PA intensity cut points for wrist-worn accelerometers. Among the three ML models, k-means cluster analysis derived the following cut points: ≤2556 counts per minute (cpm) for sedentary behavior, 2557-7064 cpm for LPA, 7065-14532 cpm for MPA, and ≥14533 cpm for VPA; in addition, k-means cluster analysis had the highest classification accuracy, with more than 70% of the total epochs being classified into the correct PA categories, as examined by the hip reference. Additionally, k-means cut points exhibited the most accurate estimates on sedentary behavior, LPA, and VPA as the hip reference. None of the three wrist methods were able to accurately assess MPA.

CONCLUSIONS

This study demonstrates the potential of ML approaches in establishing cut points for wrist-worn accelerometers to assess PA in preschoolers. However, the findings from this study warrant additional validation studies.

Effectiveness of a family-, school- and community-based intervention on physical activity and its correlates in Belgian families with an increased risk for type 2 diabetes mellitus: the Feel4Diabetes-study

Background

The study aimed to investigate the effectiveness of the European Feel4Diabetes intervention, promoting a healthy lifestyle, on physical activity and its correlates among families at risk for type 2 diabetes mellitus (based on the Finnish Diabetes Risk Score) in Belgium.

Methods

The Feel4Diabetes intervention involved three components: family, school and community component, with the family component consisting of 6 counseling sessions for families at risk. Main outcomes were objectively measured physical activity levels and its subjectively measured correlates. The final sample consisted of 454 parents (mean age 39.4 years; 72.0% women) and 444 children (mean age 8.0 years; 50.1% girls). Multilevel repeated measures analyses were performed to assess intervention effectiveness after 1 year.

Results

In parents, there was no significant intervention effect. In children, there were only significant negative effects for moderate to vigorous physical activity (p = 0.05; η_p² = 0.008) and steps (p = 0.03; η_p² = 0.006%) on weekdays, with physical activity decreasing (more) in the intervention group.

Conclusions

The F4D-intervention lacks effectiveness on high-risk families’ physical activity and its correlates in Belgium. This could partially be explained by low attendance rates and a large drop-out. To reach vulnerable populations, future interventions should invest in more appropriate recruitment (e.g. more face-to-face contact) and more bottom-up development of the intervention (i.e. co-creation of the intervention with the target group).

Trial registration

The Feel4Diabetes-study was prospectively registered at clinicaltrials.gov as NCT02393872 on 20 March 2015.

Machine Learning Models for Classifying Physical Activity in Free-Living Preschool Children

Machine learning (ML) activity classification models trained on laboratory-based activity trials exhibit low accuracy under free-living conditions. Training new models on free-living accelerometer data, reducing the number of prediction windows comprised of multiple activity types by using shorter windows, including temporal features such as standard deviation in lag and lead windows, and using multiple sensors may improve the classification accuracy under free-living conditions. The objective of this study was to evaluate the accuracy of Random Forest (RF) activity classification models for preschool-aged children trained on free-living accelerometer data. Thirty-one children (mean age = 4.0 ± 0.9 years) completed a 20 min free-play session while wearing an accelerometer on their right hip and non-dominant wrist. Video-based direct observation was used to categorize the children’s movement behaviors into five activity classes. The models were trained using prediction windows of 1, 5, 10, and 15 s, with and without temporal features. The models were evaluated using leave-one-subject-out-cross-validation. The F-scores improved as the window size increased from 1 to 15 s (62.6%–86.4%), with only minimal improvements beyond the 10 s windows. The inclusion of temporal features increased the accuracy, mainly for the wrist classification models, by an average of 6.2 percentage points. The hip and combined hip and wrist classification models provided comparable accuracy; however, both the models outperformed the models trained on wrist data by 7.9 to 8.2 percentage points. RF activity classification models trained with free-living accelerometer data provide accurate recognition of young children’s movement behaviors under real-world conditions.

Association between Compliance with the 24-Hour Movement Guidelines and Fundamental Movement Skills in Preschoolers: A Network Perspective

The present study aimed to analyze the compliance with the 24-h movement guidelines and its association with fundamental motor skills (FMS) in early childhood, considering sex and Body Mass Index (BMI) in a network perspective. Two hundred and twelve preschoolers (109 boys, 4.45 ± 0.78 years old) provided physical activity (PA), sleep duration, screen time, fundamental motor skills (FMS) and BMI data. Relationships between compliance with movement behaviors guidelines, FMS, sex and BMI were calculated using a network analysis. Only two percent of the entire sample complied with the overall 24-h movement behaviors recommendations; while the emerged network in the present study emphasized ball skills as the most critical centrality variable, according to age, reinforcing the importance of ball skills for the engagement and maintenance of PA in children. The present study presents a novel statistical and theoretical perspective that permits hitherto unseen insight into the associations between movement behavior, FMS and their correlates, that appropriately consider the inherent, multifaceted, complexity of these relationships.

Associations of participation in organized sports and physical activity in preschool children: a cross-sectional study

Background

Participation in organized sports is associated with higher physical activity (PA) levels in school-aged-children. Yet, little is known about PA determinants in preschool-aged-children. We examined associations between organized sports participation and preschoolers’ daily PA.

Methods

The study comprised 290 3–5 years old children and PA was measured for 1 week via accelerometers. Organized sports participation was parent-reported and preschool arrival and departure time was teacher-recorded. The preschool duration reported by teachers was matched with time-stamped accelerometer data to distinguish PA during preschool time and PA outside preschool time. Linear mixed models, nested on preschool level, were used to examine associations between organized sports participation and children’s PA outside preschool time, during preschool time and throughout the day.

Results

In total, 146 children (50.3%) participated in organized sports at least 1 h/week. Participation in organized sports was associated with 6.0 more minutes of moderate-to-vigorous PA (MVPA) (95% CI: 0.6, 11.3) throughout the day and 5.7 more minutes of MVPA (95% CI: 1.6, 9.7) outside preschool time after adjustment. There was no association between organized sports participation and PA during preschool time.

Conclusions

This is the first study to show positive associations between organized sports participation and preschoolers’ PA levels outside preschool time and throughout the day. In addition, findings from this study do not support PA compensation. Therefore, targeting organized sports may be successful in improving PA, even among preschoolers.