Objective Measurement of Posture and Movement in Young Children Using Wearable Sensors and Customised Mathematical Approaches: A Systematic Review

Given the importance of young children's postures and movements to health and development, robust objective measures are required to provide high-quality evidence. This study aimed to systematically review the available evidence for objective measurement of young (0-5 years) children's posture and movement using machine learning and other algorithm methods on accelerometer data. From 1663 papers, a total of 20 papers reporting on 18 studies met the inclusion criteria. Papers were quality-assessed and data extracted and synthesised on sample, postures and movements identified, sensors used, model development, and accuracy. A common limitation of studies was a poor description of their sample data, yet over half scored adequate/good on their overall study design quality assessment. There was great diversity in all aspects examined, with evidence of increasing sophistication in approaches used over time. Model accuracy varied greatly, but for a range of postures and movements, models developed on a reasonable-sized (n > 25) sample were able to achieve an accuracy of >80%. Issues related to model development are discussed and implications for future research outlined. The current evidence suggests the rapidly developing field of machine learning has clear potential to enable the collection of high-quality evidence on the postures and movements of young children.

The effect of experiential learning interventions on physical activity outcomes in children: A systematic review

BACKGROUND

This systematic review examined the effectiveness of experiential learning interventions for improving children's physical activity knowledge, attitudes, and behaviours. It also aimed to identify intervention characteristics that resulted in the greatest impact.

METHODS

Four databases: Education Research Complete, Scopus, Web of Science and PsychINFO were searched from database inception to January 2023. Eligible studies: (1) included children 0-12 years; (2) assessed the effect of physical activity outcomes on children's physical activity knowledge, attitudes or behaviour and (3) were randomised controlled trials conducted in any setting. Study risk of bias was assessed by two independent reviewers using the Cochrane risk of bias tool. Intervention approaches were categorised, and effect sizes were compared across studies for each outcome.

RESULTS

Twelve studies were included in the review: ten in school age and two in below five years. For behavioural outcomes, six of eight studies showed medium to large effects (effects size (ES) range: 0.3-0.9), two of the three studies that assessed attitudinal outcomes displayed medium effects (ES range: 0.4-0.5) and both studies that assessed knowledge outcomes displayed medium to large effects (ES range: 0.4-1.3). The two experiential learning interventions among children < 5 years demonstrated small to medium effects on behaviour change (ES range: 0.2-0.5). Effective interventions combined enjoyable practical activities (fitness activities, games and challenges), with behaviour change techniques (goal setting, and self-monitoring), were underpinned by a behaviour change theory, and were often of short duration (< 4 months) but intense (several sessions/week). Moderate to high statistical heterogeneity was observed for behaviour outcomes and risk of bias across studies was generally high.

CONCLUSIONS

This review provides some evidence supporting the effectiveness of experiential learning interventions in improving physical activity outcomes in school-aged children. Additional evidence is needed in children <5 years old. Future experiential learning interventions need to strengthen the evidence with rigorous methodological quality and clear reporting of the experiential learning components.

Longitudinal associations between weight status and academic achievement in primary school children

BACKGROUND

Evidence for longitudinal associations between childhood weight status and academic achievement remains unclear due to considerable heterogeneity in study design, measures of academic achievement and appropriate categorization of weight status.

OBJECTIVE

To examine longitudinal associations between childhood weight status (underweight, healthy weight, overweight/obese) and academic achievement in the transition from preschool to primary (elementary) school among Australian school children.

METHODS

Data were from the Healthy Active Preschool and Primary Years study. Height and weight, for calculating BMI were measured at baseline (preschool age 3-5 years; 2008/9) and follow-up (primary school age 6-8 years; 2011/12). Academic achievement was measured at age 9 years.

RESULTS

No associations between BMI z-score or weight category in the preschool years and later NAPLAN scores were found for boys. For girls, having a higher BMI z-score (B = -13.68, 95%CI: -26.61, -0.76) and being affected by overweight (B = -33.57, 95%CI: -61.50, -5.24) in preschool was associated with lower language scores. Remaining affected by overweight from preschool to primary school was associated with lower numeracy (B = -25.03, 95%CI: -49.74, -0.33), spelling (B = -33.5, 95%CI: -63.43, -3.58), language (B = -37.89, 95%CI: -72.75, -3.03) and total achievement scores (B = -24.24, 95%CI: -44.85, -3.63) among girls. For boys, becoming affected by overweight was associated with lower spelling (B = -38.76, 95%CI: -73.59, -3.93) and total achievement scores (B = -27.70, 95%CI: -54.81, -0.58).

CONCLUSIONS

Associations between being affected by overweight/obesity and poorer academic achievement were more pronounced in girls than boys, indicating potentially inequitable impacts of excess weight and highlighting the greater need for intervention among girls. However, stronger study designs are needed to confirm our findings.

Changes in subdomains of non-organized physical activity between childhood and adolescence in Australia: a longitudinal study

BACKGROUND

Physical activity (PA) participation among youth tends to be insufficient and is prone to decline with age. In Australia, this decline has been shown to particularly occur in the domain of non-organized PA (e.g. active play and informal sport) between childhood and adolescence. However, information about changes in more specific groupings of activities within non-organized PA (i.e. subdomains) is needed, as this could support more targeted intervention strategies. This study aimed to investigate changes in the duration of specific subdomains of non-organized PA between late childhood (10-11 years) and early adolescence (12-13 years) in Australia, as well as whether these changes are moderated by sex.

METHODS

Data were sourced from Waves 6 and 7 of the Longitudinal Study of Australian Children (n = 3614). Youth time-use diaries (24-h) were used to measure the duration of eight subdomains of non-organized PA at both waves (athletics/gymnastics, ball sports, cycling/motor/roller sports, fitness/gym/exercise, martial arts/dancing, water/ice/snow sports, active play and other outdoor/nature PA). Multilevel mixed modelling was used to explore longitudinal changes between waves and the potential moderation effect of sex.

RESULTS

Active play declined the most of all subdomains (β = -20.5 min/day; 95% CI = -23.4, -17.6, p < 0.001). A smaller decline was observed in the subdomain of non-organized ball sports (β = -4.1 min/day; 95% CI = -5.9, -2.3, p < 0.001). Other subdomains remained stable or had only very small changes in participation. The decline in active play was moderated by sex, with a steeper decline among girls. No other notable moderation effects were observed.

CONCLUSIONS

Future studies may seek to explore and test the acceptability of PA promotion strategies to encourage active play participation, such as 'reframing' childhood play activities to be appropriate for adolescents. Such studies might particularly seek the perspectives of girls in the transition to adolescence.

A collaborative approach to adopting/adapting guidelines. The Australian 24-hour movement guidelines for children (5-12 years) and young people (13-17 years): An integration of physical activity, sedentary behaviour, and sleep

Abstract

Background

In 2018, the Australian Government updated the Australian Physical Activity and Sedentary Behaviour Guidelines for Children and Young People. A requirement of this update was the incorporation of a 24-hour approach to movement, recognising the importance of adequate sleep. The purpose of this paper was to describe how the updated Australian 24-Hour Movement Guidelines for Children and Young People (5 to 17 years): an integration of physical activity, sedentary behaviour and sleep were developed and the outcomes from this process.

Methods

The GRADE-ADOLOPMENT approach was used to develop the guidelines. A Leadership Group was formed, who identified existing credible guidelines. The Canadian 24-Hour Movement Guidelines for Children and Youth best met the criteria established by the Leadership Group. These guidelines were evaluated based on the evidence in the GRADE tables, summaries of findings tables and recommendations from the Canadian Guidelines. We conducted updates to each of the Canadian systematic reviews. A Guideline Development Group reviewed, separately and in combination, the evidence for each behaviour. A choice was then made to adopt or adapt the Canadian recommendations for each behaviour or create de novo recommendations. We then conducted an online survey (n=237) along with three focus groups (n=11 in total) and 13 key informant interviews. Stakeholders used these to provide feedback on the draft guidelines.

Results

Based on the evidence from the Canadian systematic reviews and the updated systematic reviews in Australia, the Guideline Development Group agreed to adopt the Canadian recommendations and, apart from some minor changes to the wording of good practice statements, maintain the wording of the guidelines, preamble, and title of the Canadian Guidelines. The Australian Guidelines provide evidence-informed recommendations for a healthy day (24-hours), integrating physical activity, sedentary behaviour (including limits to screen time), and sleep for children (5-12 years) and young people (13-17 years).

Conclusions

To our knowledge, this is only the second time the GRADE-ADOLOPMENT approach has been used to develop movement behaviour guidelines. The judgments of the Australian Guideline Development Group did not differ sufficiently to change the directions and strength of the recommendations and as such, the Canadian Guidelines were adopted with only very minor alterations. This allowed the Australian Guidelines to be developed in a shorter time frame and at a lower cost. We recommend the GRADE-ADOLOPMENT approach, especially if a credible set of guidelines that was developed using the GRADE approach is available with all supporting materials. Other countries may consider this approach when developing and/or revising national movement guidelines.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-021-01236-2.

Experiential Learning Interventions and Healthy Eating Outcomes in Children: A Systematic Literature Review

Experiential learning is the process where learners create meaning from direct experience. This systematic review aimed to examine the effects of experiential learning activities on dietary outcomes (knowledge, attitudes, behaviors) in children. Four databases: Education Research Complete, Scopus, Web of Science and PsychINFO were searched from database inception to 2020. Eligible studies included children 0-12 years, assessed effect of experiential learning on outcomes of interest compared to non-experiential learning and were open to any setting. The quality of studies was assessed using the revised Cochrane risk of bias tool by two independent reviewers and effect size was calculated on each outcome. Nineteen studies were conducted in primary school, six in pre-school and one in an outside-of-school setting and used nine types of experiential learning strategies. Cooking, taste-testing, games, role-playing, and gardening were effective in improving nutrition outcomes in primary school children. Sensory evaluation, games, creative arts, and storybooks were effective for preschool children. Multiple strategies involving parents, and short/intense strategies are useful for intervention success. Experiential learning is a useful strategy to improve children's knowledge, attitudes, and behaviors towards healthy eating. Fewer studies in pre-school and outside of school settings and high risk of bias may limit the generalizability and strength of the findings.

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.

Cross-Sectional and Longitudinal Associations between 24-Hour Movement Behaviours, Recreational Screen Use and Psychosocial Health Outcomes in Children: A Compositional Data Analysis Approach

It remains unclear whether the time-use composition of 24-h movement behaviours (sleep, sedentary time (ST), physical activity (PA)) and recreational screen use are independently associated with psychosocial health. This study examined the cross-sectional and longitudinal associations between 24-h movement behaviour composition, recreational screen use and psychosocial health outcomes in children. Measures completed at baseline (n = 127; 11.7 years) and follow-up (n = 88; 12.8 years) included accelerometer-based 24-h movement behaviours, self-reported recreational screen use and psychosocial health (Strengths and Difficulties Questionnaire, Kessler’s Psychological Distress Scale). Linear mixed models were used to examine the cross-sectional and longitudinal associations between the 24-h movement behaviour composition and recreational screen use levels with psychosocial health outcomes. Overall, the movement behaviour composition (p < 0.05) and recreational screen use levels (p < 0.01) were both cross-sectionally but not longitudinally associated with psychosocial health outcomes. Relative to other behaviours, sleep was negatively associated, while light-intensity PA was positively associated with internalising problems and total difficulties scores. ST was positively associated with internalising problems. High levels of recreational screen use (>2 h/day) were associated with greater externalising problems, total difficulties scores and psychological distress. These findings reinforce the importance of achieving a balance between different types of movement behaviours over a 24-h period for psychosocial health.

Association between green space quality and prosocial behaviour: A 10-year multilevel longitudinal analysis of Australian children

BACKGROUND

Current evidence from studies on green space and child prosocial behaviour suggests a paucity of studies investigating the plausible role of green space quality in shaping the development of prosocial behaviour. This study aimed to examine longitudinal association between green space quality and prosocial behaviour among children.

METHODS

We analysed 10-year longitudinal data (2004-2014) from the Longitudinal Study of Australian Children (LSAC), a nationally representative cohort study. Prosocial behaviour that covers positive behaviours (e.g. sharing, helping) was measured using a prosocial scale from Goodman's Strengths and Difficulties Questionnaire (SDQ). Parents' perceptions on the availability of "good" parks, playgrounds, and play space in the neighbourhood assessed green space quality. Multilevel linear regression models were used to examine potential changes in prosocial behaviour across childhood in relation to green space quality. A two-way interaction term between green space and age was fitted to assess potential differences in the effect of green space quality by age. Sensitivity analyses by child's sex and history of residential movement were also performed.

RESULTS

From the analysis of 24,418 observations nested in 4969 children, prosocial behaviour was relatively high (mean = 8.13 out of 10; SD = 1.79) and about balanced proportions between girls (48.74%) and boys (51.26%) were included. Prosocial behaviour was higher among children whose parents agreed (β = 0.10; 95%CI = 0.04, 0.16) and strongly agreed (β = 0.20; 95%CI = 0.13, 0.27) to having quality green space in their neighbourhood. The benefit of exposure to favourable green space on prosocial behaviour was similar among both children who changed and did not change neighbourhood, but reported higher among boys than girls. Younger compared with older children or adolescents tended to benefit more by the presence of quality green space.

CONCLUSION

Green space quality was positively associated with child prosocial behaviour. Boys and younger children tended to benefit more from quality green space. Future research might seek to identify preferred characteristics of quality green spaces, and to understand how these preferences vary by gender and age, to best support the development of prosocial behaviour across childhood and adolescence.

Changes in 24-hour movement behaviours during the transition from primary to secondary school among Australian children

This study examined concurrent changes in all components of 24-h movement behaviours (24-h MB) (sleep, sedentary behaviour [SB] and physical activity [PA]) and compliance with the Australian 24-Hour Movement Guidelines over the primary to the secondary school transition period. The analytical sample included 83 children (60.2% girls) who provided valid accelerometer-measured 24-h MB data during their final year of primary school (T1) and first year of secondary school (T2). Self-reported participation in domain-specific SB and PA, socio-demographic characteristics and weight status were also assessed. Change in 24-h MB composition from T1 to T2 was analysed using a compositional multivariate linear model for repeated measures. The difference in the proportion of meeting the 24-hour integrated movement guidelines was assessed using a McNemar-Bowker test. An unfavourable change was observed in the 24-h MB composition (p < .0001), with increased time spent in SB (+58 min/day) and decreased time in sleep (-13 min/day), Iight-intensity PA (-13 min/day) and moderate- to vigorous-intensity PA (-14 min/day). Domain-specific SB results indicated an increase in recreational screen time (+45 min/day) and out-of-school educational activities (+25 min/day). No significant changes were observed for domain-specific PA. The proportion of children meeting the 24-hour integrated movement guidelines also declined (20.5% vs. 3.6%; p < .0001). Change in 24-h MB was larger on weekdays than weekends (p < .0001); but this was not moderated by socio-demographic characteristics or weight status. These findings suggest that an integrated intervention approach targeting weekdays may be beneficial to promote adherence to healthy 24-h MB during the primary to the secondary school transition period. HighlightsThis study investigated how the 24-hour movement behaviour composition (i.e., time spent in sleep, sedentary behaviour and physical activity) changes and its impact on children's compliance with the 24-hour integrated movement guidelines during the primary to secondary school transition period.There was an unfavourable change in the accelerometer-measured 24-hour movement behaviour composition, with increased time spent in sedentary behaviour and decreased time in sleep, light-intensity physical activity and moderate- to vigorous-intensity physical activity. The change in weekday composition was significantly more prominent than change on weekends.The observed increase in sedentary behaviour may be attributed in part to an increase in recreational screen time and out-of-school educational activities in secondary schools.These behavioural changes were reflected in decreased compliance rates with the individual and integrated 24-hour movement guidelines, with the largest decline observed in the sleep guideline.Our findings highlight the need for an integrated intervention approach to support children to develop and/or maintain healthy movement behaviour habits throughout the school transition period.

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.

School Flexible Learning Spaces, Student Movement Behavior and Educational Outcomes among Adolescents: A Mixed-Methods Systematic Review

BACKGROUND

To achieve sustainability, we must consider scalable improvements in student movement behavior in the classroom setting, educational priorities. Flexible learning spaces that employ student-centered pedagogy and contain a range of furniture and layout options, implemented to improve educational outcomes, may enable unintended health benefits. In this review, we summarize the evidence on the effects of flexible learning spaces on adolescent student movement behaviors and educational outcomes.

METHODS

We searched 5 databases, retrieving 5 quantitative and one qualitative article meeting the review criteria.

RESULTS

Students in flexible learning spaces spent less time sitting, and more time standing and moving. Students were also more engaged, on-task, and collaborated and interacted more. Academic results for English, Mathematics and Humanities for those in flexible learning spaces were higher than peers in traditional classrooms.

CONCLUSION

Evidence from the reviewed studies suggests that there may be beneficial outcomes across some movement behaviors as well as learning outcomes in classrooms that employ student-centered pedagogy and use a built environment that facilitates autonomy and choice around where and how to learn. These learning environments present an opportunity for an interdisciplinary approach to address sedentary behavior in classrooms.

Socio-ecological predictors of non-organized physical activity participation and decline between childhood and adolescence

Physical activity (PA) tends to decline during late childhood and adolescence. In Australia, this decline has been shown to particularly occur non-organized PA (e.g., active play, informal sport). This study aimed to explore predictors of non-organized PA at 13y; and decline between 11y and 13y. Data were sourced from the Longitudinal Study of Australian Children. Non-organized PA was measured using time-use diaries. Analyses included Cragg hurdle and binary logistic regressions. The likelihood of non-organized PA at 13y was predicted by PA enjoyment (OR = 1.36, p = 0.007), number of siblings (OR = 1.11, p < 0.001), sex (females) (OR = 0.66, p < 0.001) and home computer use at 11y (OR = 0.98, p = 0.002) (n = 3,193). Females also engaged in less non-organized PA at 13y (β = -77.77, p = 0.048) (n = 3,193). Significant predictors of decline in non-organized PA were socioeconomic position (OR = 0.92, p = 0.047) and sugary drink consumption at 11y (OR = 1.06, p = 0.033) (n = 3,222). Strategies to promote non-organized PA may include targeting females and those of lower socioeconomic position, and focusing on types of PA that may replace the perceived benefits of computer use.

The Relationship Between Green Space and Prosocial Behaviour Among Children and Adolescents: A Systematic Review

The plausible role of nearby green space in influencing prosocial behaviour among children and adolescents has been studied recently. However, no review has been conducted of the evidence testing the association between green space and prosocial behaviour. This systematic review addresses this gap among children and adolescents. Within this review, we propose a conceptual framework describing potential pathways linking green space to prosocial behaviour, discuss the direction, magnitude, moderators, and mediators of the association, and develop a narrative synthesis of future study directions. Out of 63 extracted associations from 15 studies, 44 were in the positive or expected direction, of which 18 were reported to be statistically significant (p < 0.05). Overall, the current evidence shows that exposure to green space may potentially increase prosocial behaviour among children and adolescents, with some contingencies (e.g., child's sex and ethnic background). However, the volume and quality of this evidence is not yet sufficient to draw conclusions on causality. Further, heterogeneity in the indicators of green space exposure could lead to mixed findings. In addition, none of the included studies investigated potential mediators. Nevertheless, this review provides preliminary evidence and a basis for further investigation with rigorous study methodology capable of drawing causal inferences and testing potential effect modifiers, linking pathways, and relevant green space measures.

Correlates of sedentary time in young children: A systematic review

Background: Young children appear to spend large portions of their waking time being sedentary. Understanding the correlates of sedentary time would assist in developing effective interventions among young children. The purpose of this systematic review was to summarize the current literature on the correlates of objectively measured sedentary time in young children aged 1-5.99y. Methods: This review was registered with PROSPERO (registration no. CRD42017081374) and aligned with the PRISMA Statement for systematic reviews. Five electronic databases (MEDline, CINAHL Complete, PsycINFO, SportDiscus, Scopus) were searched up to October 26, 2017 for studies investigating correlates of sedentary time measured using objective devices. A semiquantitative approach was used to synthesize data. Results: Forty-five studies were retrieved comprising 13,430 participants, and 84 correlates of sedentary time in young children were evaluated. The associations between sex, sleep habits, daily patterns (childcare vs. non-childcare hours), childcare type and sedentary time were indeterminate. Thirty-nine correlates were consistently unrelated. Forty-one potential correlates were examined in too few studies (<4) to make confident conclusions. Parental sedentary behaviour was reported 3 times and maternal sedentary behaviour was reported once. Out of these four studies, three were positively associated with child sedentary time. Conclusions: Despite reviewing 45 studies that evaluated associations for 84 correlates, this review was unable to identify any consistent correlates of sedentary time in young children. Additional research is needed in this area to provide robust evidence of the correlates of sedentary time in young children, particularly for those examined in only a small number of studies.

'Jump start' childcare-based intervention to promote physical activity in pre-schoolers: six-month findings from a cluster randomised trial

BACKGROUND

Participation in adequate levels of physical activity during the early years is important for health and development. We report the 6-month effects of an 18-month multicomponent intervention on physical activity in early childhood education and care (ECEC) settings in low-income communities.

METHODS

A cluster randomised controlled trial was conducted in 43 ECEC settings in disadvantaged areas of New South Wales, Australia. Three-year-old children were recruited and assessed in the first half of 2015 with follow-up 6 months later. The intervention was guided by Social Cognitive Theory and included five components. The primary outcome was minutes per hour in total physical activity during ECEC hours measured using Actigraph accelerometers. Intention-to-treat analysis of the primary outcome was conducted using a generalized linear mixed model.

RESULTS

A total of 658 children were assessed at baseline. Of these, 558 (85%) had valid accelerometer data (mean age 3.38y, 52% boys) and 508 (77%) had valid accelerometry data at 6-month follow-up. Implementation of the intervention components ranged from 38 to 72%. There were no significant intervention effects on mins/hr. spent in physical activity (adjusted difference = - 0.17 mins/hr., 95% CI (- 1.30 to 0.97), p = 0.78). A priori sub-group analyses showed a greater effect among overweight/obese children in the control group compared with the intervention group for mins/hr. of physical activity (2.35mins/hr., [0.28 to 4.43], p = 0.036).

CONCLUSIONS

After six-months the Jump Start intervention had no effect on physical activity levels during ECEC. This was largely due to low levels of implementation. Increasing fidelity may result in higher levels of physical activity when outcomes are assessed at 18-months.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry  ACTRN12614000597695.

'Social screens' and 'the mainstream': longitudinal competitors of non-organized physical activity in the transition from childhood to adolescence

Background

Physical activity (PA) tends to decline during late childhood and adolescence. In Australia, this decline has been shown to occur particularly in non-organized PA (e.g. active play and informal sport). Using a social marketing approach, segments of youth may be identified and targeted based on their profile of alternative activities that compete with non-organized PA during the transition to adolescence. The objectives of this study were to identify and describe segments of youth whose participation in non-organized PA declined between 11 and 13 years, based on changes in other potential competing activities during this period.

Methods

Data were sourced from Waves 4 and 5 of the Longitudinal Study of Australian Children. Participation in non-organized PA and thirteen alternative activities (e.g. video games, homework, sleep) were measured using 24-h time-use diaries. Analyses were limited to participants whose non-organized PA had declined between 11 and 13 years (n = 1043). Two-stage cluster analysis was conducted and segments were described using chi-square and t-tests.

Results

Among the analytic sample, average non-organized PA participation declined by 87 min/day between 11y and 13y (p < 0.001). Two segments were identified (κ = 0.66). The ‘Social Screens’ segment (n = 143) had large increases in texting, emailing and social media use (+ 56 min/day, p < 0.001) and other internet use (+ 32 min/day, p < 0.001). Conversely, ‘the Mainstream’ segment (n = 900) had smaller increases in a wider range of activities, including other PA (organized PA, active transport, active chores/work) (+ 16.0 min/day, p < 0.001), homework/study (+ 9.5 min/day, p < 0.001) and electronic gaming (+ 6.7 min/day, p < 0.05). ‘Social Screens’ were more likely to attend public school, live in urban areas and have more advanced pubertal development (girls only). ‘The Mainstream’ were more likely to participate in PA and out-of-school activities.

Conclusions

The ‘Social Screens’ segment had a much larger increase in texting, emailing, social media and other internet use, and lower participation in overall PA and out-of-school activities, compared with ‘the Mainstream’. Future research may trial PA promotion strategies to replace benefits that this segment may seek in competing activities (e.g. social PA apps).

Flexible learning spaces facilitate interaction, collaboration and behavioural engagement in secondary school

Globally, many schools are replacing traditional classrooms with innovative flexible learning spaces to improve academic outcomes. Little is known about the effect on classroom behaviour. Students from nine secondary schools (n = 60, M age = 13.2±1.0y) were observed via momentary time sampling for a 30 minute period, in both a traditionally furnished and arranged classroom and a flexible learning space containing a variety of furniture options to accommodate different pedagogical approaches and learning styles. The teaching approaches in both conditions were documented. In traditional classrooms the approach was predominantly teacher-led and in the flexible learning space it was student-centred. Students in flexible learning spaces spent significantly more time in large group settings (d = 0.61, p = 0.001), collaborating (d = 1.33, p = 0.001), interacting with peers (d = 0.88, p = 0.001) and actively engaged (d = 0.50, p = 0.001) than students in traditional classrooms. Students also spent significantly less class time being taught in a whole class setting (d = -0.65, p = 0.001), engaged in teacher-led instruction (d = -0.75, p = 0.001), working individually (d = -0.79, p = 0.001), verbally off-task (d = -0.44, p = 0.016), and using technology (d = -0.26, p = 0.022) than in traditional classrooms. The results suggest that the varied, adaptable nature of flexible learning spaces coupled with the use of student-centred pedagogies, facilitated a higher proportion of class time interacting, collaborating and engaging with the lesson content. This may translate into beneficial learning outcomes in the long-term.

Concurrent validity of the ActiGraph GT3X+ and activPAL for assessing sedentary behaviour in 2-3-year-old children under free-living conditions

OBJECTIVES

ActiGraph accelerometer cut-points are commonly used to classify sedentary behaviour (SB) in young children. However, they vary from 5counts/5s to 301counts/15s, resulting in different estimates and inconsistent findings. The aim was to examine the concurrent validity of ActiGraph GT3X+cut-points against the activPAL for measuring SB in 2-3-year-olds during free-living conditions.

DESIGN

Observational validation-study.

METHODS

Sixty children were fitted with the activPAL and ActiGraph simultaneously for at least 2h. Nine ActiGraph cut-points ranging from 60 to 1488 counts per minute were used to derive SB. Bland & Altman plots and equivalent tests were performed to assess agreement between methods.

RESULTS

Estimates of SB according to the different ActiGraph cut-points were not within the activPAL ±10% equivalent interval (-4.05; 4.05%). The ActiGraph cut-points that showed the lower bias were 48counts/15s (equivalence lower limit: p= 0.597; equivalence upper limit: p<0.001; bias: -4.46%; limits of agreement [LoA]: -21.07 to 30.00%) and 5counts/5s (equivalence lower limit: p<0.001; equivalence upper limit: p= 0.737; bias: -5.11%; LoA: 30.43 to 20.20%). For the 25counts/15s, 37counts/15s and 48counts/15s ActiGraph cut-points, the upper limits were within the equivalent interval (p<0.001) but not the lower limits (p>0.05). When using the 5counts/5s and 181counts/15s ActiGraph cut-points, lower limits were within the equivalent interval (p<0.001) but not the upper limits (p>0.05). Confidence intervals of the remaining ActiGraph cut-points lie outside the equivalent interval.

CONCLUSIONS

Although none of the ActiGraph cut-points provided estimates of SB that were equivalent to activPAL; estimates from 48counts/15s and 5counts/5s displayed the smallest mean bias (˜5%).

Longitudinal Associations of Electronic Application Use and Media Program Viewing with Cognitive and Psychosocial Development in Preschoolers

OBJECTIVE

To investigate associations of traditional (program viewing) and contemporary (electronic applications, or apps) electronic media use with preschoolers' executive function and psychosocial development 12 months later.

METHODS

We conducted an analysis of longitudinal data from 185 children (mean age, 4.2 ± 0.6 years). Parents reported children's weekly electronic media use: 1) viewing programs on television or other devices and 2) app and game play using tablets, computers, consoles, or other devices. Direct assessments of children's executive functions (working memory, inhibition, and shifting) and educator-reported psychosocial difficulties were also collected. Linear regression models assessed associations between baseline predictors and developmental outcomes 12 months later, adjusting for covariates, preschool clustering, and baseline levels of predictors.

RESULTS

Higher levels of program viewing at baseline were significantly associated with increases in externalizing behaviors (β = 0.008; 95% confidence interval [CI], 0.002-0.014; P = .010) and total difficulties (β = 0.013; 95% CI, 0.005-0.022; P = .005) at follow-up. High-dose app users (≥30 min/d) had a significantly lower inhibition score (mean difference = -0.04; 95% CI: -0.09 to -0.00; P = .044) at follow-up compared to low-dose app users (1 to 29 min/d).

CONCLUSIONS

Limiting electronic app use to <30 min/d and limiting media program viewing may be positively associated with preschool children's cognitive and psychosocial development.

Flexible learning spaces reduce sedentary time in adolescents

OBJECTIVES

Many schools internationally are replacing traditional classrooms (TC) with innovative flexible learning spaces (FLS) to improve academic outcomes. Via a stealth approach, there may be additional unintended health benefits if students reduce their total and prolonged sitting. The aim of this study was to compare student sitting patterns between TC and FLS.

DESIGN

School-based cross-over trial.

METHODS

Students at nine secondary schools (n=191, M age=13.2±1.0years) wore activPAL accelerometers in both a traditionally furnished and arranged classroom (TC), and a FLS containing a variety of furniture and layout options, utilizing student-centered pedagogies, for the duration of one double classroom lesson (M=76min). The lesson content and teacher were consistent across both conditions. Data were analyzed using multilevel mixed-effects linear regression.

RESULTS

In FLS, students spent less class time sitting (mean=18%; 95% CI: -20.8, -15.0), and accumulated more breaks in sitting (2.1; 95% CI: 0.8, 3.5 per 60min), more bouts of intermittent (≤9min) sitting (2.2; 95% CI: 0.8, 3.6 per 60min), and fewer bouts of prolonged (≤30min) sitting (-0.2; 95% CI: -0.3, -0.1 per 60min), than in TC. Students also spent more class time standing (15%; 95% CI: 12.7, 18.0) and stepping (3%; 95% CI: 2.0, 3.1) in FLS than TC.

CONCLUSION

The results suggest that, by stealth, elements of FLS including a variety of furniture and resources, and greater use of student-centered pedagogies, facilitate improvements in adolescents' sedentary profiles during class time. This may translate into beneficial health impacts over a longer period given the health benefits of reducing total and breaking up prolonged sitting.

Sensor-enabled Activity Class Recognition in Preschoolers: Hip versus Wrist Data

PURPOSE

Pattern recognition approaches to accelerometer data processing have emerged as viable alternatives to cut-point methods. However, few studies have explored the validity of pattern recognition approaches in preschoolers, and none have compared supervised learning algorithms trained on hip and wrist data. Purpose of this study was to develop, test, and compare activity class recognition algorithms trained on hip, wrist, and combined hip and wrist accelerometer data in preschoolers.

METHODS

Eleven children 3-6 yr of age (mean age, 4.8 ± 0.9 yr) completed 12 developmentally appropriate physical activity (PA) trials while wearing an ActiGraph GT3X+ accelerometer on the right hip and nondominant wrist. PA trials were categorized as sedentary, light activity games, moderate-to-vigorous games, walking, and running. Random forest (RF) and support vector machine (SVM) classifiers were trained using time and frequency domain features from the vector magnitude of the raw signal. Features were extracted from 15-s nonoverlapping windows. Classifier performance was evaluated using leave-one-out cross-validation.

RESULTS

Cross-validation accuracy for the hip, wrist, and combined hip and wrist RF models was 0.80 (95% confidence interval (CI), 0.79-0.82), 0.78 (95% CI, 0.77-0.80), and 0.82 (95% CI, 0.80-0.83), respectively. Accuracy for hip, wrist, and combined hip and wrist SVM models was 0.81 (95% CI, 0.80-0.83), 0.80 (95% CI, 0.79-0.80), and 0.85 (95% CI, 0.84-0.86), respectively. Recognition accuracy was consistently excellent for sedentary (>90%); moderate for light activity games, moderate-to-vigorous games, and running (69%-79%); and modest for walking (61%-71%).

CONCLUSIONS

Machine learning algorithms such as RF and SVM are useful for predicting PA class from accelerometer data collected in preschool children. Although classifiers trained on hip or wrist data provided acceptable recognition accuracy, the combination of hip and wrist accelerometer delivered better performance.

Wrist Acceleration Cut Points for Moderate-to-Vigorous Physical Activity in Youth

PURPOSE

This study aimed to examine the validity of wrist acceleration cut points for classifying moderate (MPA), vigorous (VPA), and moderate-to-vigorous (MVPA) physical activity.

METHODS

Fifty-seven children (5-12 yr) completed 15 semistructured activities. Three sets of wrist cut points (>192 mg, >250 mg, and >314 mg), previously developed using Euclidian norm minus one (ENMO192+), GENEActiv software (GENEA250+), and band-pass filter followed by Euclidian norm (BFEN314+), were evaluated against indirect calorimetry. Analyses included classification accuracy, equivalence testing, and Bland-Altman procedures.

RESULTS

All cut points classified MPA, VPA, and MVPA with substantial accuracy (ENMO192+: κ = 0.72 [95% confidence interval = 0.72-0.73], MVPA: area under the receiver operating characteristic curve (ROC-AUC) = 0.85 [0.85-0.86]; GENEA250+: κ = 0.75 [0.74-0.76], MVPA: ROC-AUC = 0.85 [0.85-0.86]; BFEN314+: κ = 0.73 [0.72-0.74], MVPA: ROC-AUC = 0.86 [0.86-0.87]). BFEN314+ misclassified 19.7% non-MVPA epochs as MPA, whereas ENMO192+ and GENEA250+ misclassified 32.6% and 26.5% of MPA epochs as non-MVPA, respectively. Group estimates of MPA time were equivalent (P < 0.01) to indirect calorimetry for the BFEN314+ MPA cut point (mean bias = -1.5%, limits of agreement [LoA] = -57.5% to 60.6%), whereas estimates of MVPA time were equivalent (P < 0.01) to indirect calorimetry for the ENMO192+ (mean bias = -1.1%, LoA = -53.7% to 55.9%) and GENEA250+ (mean bias = 2.2%, LoA = -56.5% to 52.2%) cut points. Individual variability (LoA) was large for MPA (min: BFEN314+, -60.6% to 57.5%; max: GENEA250+, -42.0% to 104.1%), VPA (min: BFEN314+, -238.9% to 54.6%; max: ENMO192+, -244.5% to 127.4%), and MVPA (min: ENMO192+, -53.7% to 55.0%; max: BFEN314+, -83.9% to 25.3%).

CONCLUSION

Wrist acceleration cut points misclassified a considerable proportion of non-MVPA and MVPA. Group-level estimates of MVPA were acceptable; however, error for individual-level prediction was larger.

Longitudinal changes in domains of physical activity during childhood and adolescence: A systematic review

OBJECTIVES

Physical activity (PA) participation is prone to decline during adolescence. An understanding of the domains of PA that are susceptible to decline may support a more targeted approach to PA and health promotion. The aim of this study was to review longitudinal trends in participation in four PA domains during childhood and adolescence: organized PA, non-organized PA, active transport and active chores.

DESIGN

Systematic review.

METHODS

5517 research articles were sourced from five electronic databases (covering January 1997-April 2018). Eligibility criteria included repeated measurements of at least one PA domain among the same participants (5-18years of age).

RESULTS

23 studies were included, cumulatively reporting data from 27,231 participants. Few studies had a low risk of bias (n=6). Most studies of active transport reported an increase in participation during childhood, no change in the transition to adolescence, and no change or decline during adolescence. Most studies of organized PA reported an increase during childhood, an increasing or stable pattern in the transition to adolescence, and no change or decline during adolescence. Non-organized PA participation tended to remain stable among adolescent girls and decline among adolescent boys. Active chores increased during the transition to adolescence and then stabilized.

CONCLUSIONS

Potential strategies for PA promotion among youth may include targeting non-organized PA among adolescent boys or organized PA among late adolescent boys and girls. However, there is a continuing need for high-quality, longitudinal studies of participation in PA domains, particularly non-organized PA and active chores. PROSPERO Registration: CRD42017076888.

Prevalence of objectively measured sedentary behavior in early years: Systematic review and meta-analysis

BACKGROUND

The early years have been identified as a critical period during which sedentary habits may be established, as this behavior appears to track throughout life.

OBJECTIVE

The purpose of this systematic review and meta-analysis is to summarize the current literature on the prevalence of sedentary behavior in children aged 1-5.99 years, reporting differences between boys and girls, weekdays and weekend days, childcare hours and nonchildcare hours, and between time spent indoors and outdoors while children attended childcare.

METHODS

Five databases were searched until 26.10.2017 and meta-analyses were conducted to estimate prevalence and calculate mean differences in prevalence between groups.

RESULTS

Fifty studies representing 14 598 children (2-5.99 years) were included. Children spent 51.4% of their waking time in sedentary behaviors. Boys spent less time being sedentary than girls (estimate difference = -1.4%; 95%CI = -2.0: -0.7; P < .001). No significant differences were found between weekdays/weekend days (estimate difference = -0.4; 95%CI = -2.0: 1.2; P = .61) nor between childcare hours/nonchildcare hours (estimate difference = %; 95%CI = -0.9: 6.6; P = .136). While attending childcare centers, children were more sedentary indoors than outdoors (estimate difference = 14.4%; 95%CI = 11.8: 16.9; P < .001).

CONCLUSIONS

Our results suggest that young children spend a significant portion of their waking hours in sedentary behaviors. While at childcare, young children accumulated more sedentary behavior indoors than outdoors. Girls were more likely to be more sedentary than boys. No significant differences were found between weekdays and weekends, or between childcare and nonchildcare hours. There is a need for higher-quality studies with strong designs, using age and device appropriate cut-off points, to improve evidence-base and to better establish prevalence of sedentary behavior in young children.

Organised sports participation and adiposity among a cohort of adolescents over a two year period

Background

Overweight and obesity among young people is alarmingly high. While hundreds of millions of children participate in organised sports worldwide, it is currently unknown whether time spent in organised sports is associated with levels of adiposity among young people. This study aimed to investigate bidirectional associations between participation in organised sports and adiposity over a two year period.

Method

Data were drawn from the Longitudinal Study of Australian Children. In total, 4033 participants (51% male) reported time spent in organised sports and had their body mass index, body fat percentage, and waist circumference measured at age 12, and again two years later. A cross-lagged panel model was used to examine bidirectional relationships over time, as well as interaction effects.

Results

Total sport participation at age 12 was not associated with subsequent BMI-z scores (β = 0.01 [95% CI, -0.02, 0.04]), body fat (β = 0.01 [95% CI, -0.02, 0.03]), or waist circumference (β = -0.01 [95% CI, -0.05, 0.02]). Similarly, measure of adiposity at age 12 were not associated with subsequent sports participation (BMI-z score: β = -0.01 [95% CI, -0.02, 0.04]; body fat percentage: β = -0.02 [95% CI, -0.05, 0.02]; waist circumference: β = -0.01 [95% CI, -0.01, 0.03]). There were no differences in the strength or direction of the relationships by type of sport or by sex (p < .05).

Conclusion

Policy and programmatic changes may be needed before organised youth sports are considered a preventative strategy for overweight and obesity. However, a more nuanced understanding of why organised youth sports are not associated with adiposity is needed before evidence-based changes can be made.

Early Childhood Media Exposure and Self-Regulation: Bidirectional Longitudinal Associations

OBJECTIVE

To investigate: 1) prospective associations between media exposure (television viewing, computers, and electronic games) at 2 years and self-regulation at 4 and 6 years, and 2) bidirectional associations between media exposure and self-regulation at 4 and 6 years. We hypothesized that media exposure and self-regulation would show a negative prospective association and subsequent bidirectional inverse associations.

METHODS

Data from the nationally-representative Longitudinal Study of Australian Children when children were aged 2 years (n = 2786) and 4/6 years (n = 3527) were used. Primary caregivers reported children's weekly electronic media exposure. A composite measure of self-regulation was computed from caregiver-, teacher-, and observer-report data. Associations were examined using linear regression and cross-lagged panel models, accounting for covariates.

RESULTS

Lower television viewing and total media exposure at 2 years were associated with higher self-regulation at 4 years (both β = -0.02; 95% confidence interval [CI], -0.03 to -0.01). Lower self-regulation at 4 years was also significantly associated with higher television viewing (β = -0.15; 95% CI, -0.21 to -0.08), electronic game use (β = -0.05; 95% CI, -0.09 to -0.01), and total media exposure (β = -0.19; 95% CI, -0.29 to -0.09) at 6 years. However, media exposure at 4 years was not associated with self-regulation at 6 years.

CONCLUSIONS

Although media exposure duration at 2 years was associated with later self-regulation, and self-regulation at 4 years was associated with later media exposure, associations were of small magnitude. More research is needed to examine content quality, social context, and mobile media use and child self-regulation.

Feasibility, acceptability, and potential efficacy of a childcare-based intervention to reduce sitting time among pre-schoolers: A pilot randomised controlled trial

The aim of this study was to test the feasibility, acceptability and potential efficacy of a childcare-based intervention to reduce total and prolonged sitting time in pre-schoolers. Four centres and 115 pre-schoolers (44 % boys; 4.1y) participated in a 3-month, 2-arm pilot cluster randomised controlled trial. Feasibility and acceptability were assessed through observations and semi-structured interviews. Sitting time, and breaks and bouts of sitting during childcare were assessed using an activPAL accelerometer over a one-week period at pre- and post-test (12wks). EF (inhibition, working memory and shifting) was assessed using the Early Years Toolbox. Intervention fidelity was high for both intervention centres (77 % vs 70 %) and educators reacted positively to the intervention. Proportion of sitting time per day reduced significantly at post-test in both intervention (-5.3%/day,[2.13, 8.50]) and control centres (-6.45 %,[4.20, 8.71]), resulting in a non- significant between-group difference (p = 0.51[2.4, 4.9]). EF scores did not significantly differ between groups (p > 0.05). Modifications to the childcare environment to reducing sitting, particularly the standing workstations, were feasible and acceptable to educators and children. No differences in sitting time between groups were seen; additional changes and longer-term trials are needed to reduce sitting time in pre-schoolers.

Converting between estimates of moderate-to-vigorous physical activity derived from raw accelerations measured at the wrist and from ActiGraph counts measured at the hip: the Rosetta Stone

The ability to compare published group-level estimates of objectively measured moderate-to-vigorous physical activity (MVPA) across studies continues to increase in difficulty. The objective of this study was to develop conversion equations and demonstrate their utility to compare estimates of MVPA derived from the wrist and hip. Three studies of youth (N = 232, 9-12yrs, 50% boys) concurrently wore a hip-worn ActiGraph and a wrist-worn GENEActiv for 7-days. ActiGraph hip count data were reduced using four established cutpoints. Wrist accelerations were reduced using the Hildebrand MVPA 200 mg threshold. Conversion equations were developed on a randomly selected subsample of 132 youth. Equations were cross-validated and absolute error, absolute percent error, and modified Bland-Altman plots were evaluated for conversion accuracy. Across equations R²_adj was 0.51-0.56 with individual-level absolute error in minutes ranging from 7 (wrist-to-hip Puyau) to 14.5 minutes (wrist-to-hip Freedson 3MET) and absolute percent differences ranging from 13.9%-24.5%. Group-level cross-validation to convert hip-to-wrist MVPA resulted in average absolute percent errors ranging from 3.1%-4.9%. Conversion of wrist-to-hip MVPA resulted in average absolute percent errors ranging from 3.0%-10.0%. We recommend the use of these equations to compare published estimates of MVPA between the wear-site cut-point combinations presented.

Adherence to 24-Hour Movement Guidelines for the Early Years and associations with social-cognitive development among Australian preschool children

Background

The new Australian 24-Hour Movement Guidelines for the Early Years recommend that, for preschoolers, a healthy 24-h includes: i) ≥180 min of physical activity, including ≥60 min of energetic play, ii) ≤1 h of sedentary screen time, and iii) 10–13 h of good quality sleep. Using an Australian sample, this study reports the proportion of preschool children meeting these guidelines and investigates associations with social-cognitive development.

Methods

Data from 248 preschool children (mean age = 4.2 ± 0.6 years, 57% boys) participating in the PATH-ABC study were analyzed. Children completed direct assessments of physical activity (accelerometry) and social cognition (the Test of Emotional Comprehension (TEC) and Theory of Mind (ToM)). Parents reported on children’s screen time and sleep. Children were categorised as meeting/not meeting: i) individual guidelines, ii) combinations of two guidelines, or iii) all three guidelines. Associations were examined using linear regression adjusting for child age, sex, vocabulary, area level socio-economic status and childcare level clustering.

Results

High proportions of children met the physical activity (93.1%) and sleep (88.7%) guidelines, whereas fewer met the screen time guideline (17.3%). Overall, 14.9% of children met all three guidelines. Children meeting the sleep guideline performed better on TEC than those who did not (mean difference [MD] = 1.41; 95% confidence interval (CI) = 0.36, 2.47). Children meeting the sleep and physical activity or sleep and screen time guidelines also performed better on TEC (MD = 1.36; 95% CI = 0.31, 2.41) and ToM (MD = 0.25; 95% CI = −0.002, 0.50; p = 0.05), respectively, than those who did not. Meeting all three guidelines was associated with better ToM performance (MD = 0.28; 95% CI = −0.002, 0.48, p = 0.05), while meeting a larger number of guidelines was associated with better TEC (3 or 2 vs. 1/none, p < 0.02) and ToM performance (3 vs. 2, p = 0.03).

Conclusions

Strategies to promote adherence to the 24-Hour Movement Behaviour Guidelines for the Early Years among preschool children are warranted. Supporting preschool children to meet all guidelines or more guidelines, particularly the sleep and screen time guidelines, may be beneficial for their social-cognitive development.

A collaborative approach to adopting/adapting guidelines - The Australian 24-Hour Movement Guidelines for the early years (Birth to 5 years): an integration of physical activity, sedentary behavior, and sleep

Background

In 2017, the Australian Government funded the update of the National Physical Activity Recommendations for Children 0–5 years, with the intention that they be an integration of movement behaviours across the 24-h period. The benefit for Australia was that it could leverage research in Canada in the development of their 24-h guidelines for the early years. Concurrently, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group published a model to produce guidelines based on adoption, adaption and/or de novo development using the GRADE evidence-to-decision framework. Referred to as the GRADE-ADOLOPMENT approach, it allows guideline developers to follow a structured and transparent process in a more efficient manner, potentially avoiding the need to unnecessarily repeat costly tasks such as conducting systematic reviews. The purpose of this paper is to outline the process and outcomes for adapting the Canadian 24-Hour Movement Guidelines for the Early Years to develop the Australian 24-Hour Movement Guidelines for the Early Years guided by the GRADE-ADOLOPMENT framework.

Methods

The development process was guided by the GRADE-ADOLOPMENT approach. A Leadership Group and Consensus Panel were formed and existing credible guidelines identified. The draft Canadian 24-h integrated movement guidelines for the early years best met the criteria established by the Panel. These were evaluated based on the evidence in the GRADE tables, summaries of findings tables and draft recommendations from the Canadian Draft Guidelines. Updates to each of the Canadian systematic reviews were conducted and the Consensus Panel reviewed the evidence for each behaviour separately and made a decision to adopt or adapt the Canadian recommendations for each behaviour or create de novo recommendations. An online survey was then conducted (n = 302) along with five focus groups (n = 30) and five key informant interviews (n = 5) to obtain feedback from stakeholders on the draft guidelines.

Results

Based on the evidence from the Canadian systematic reviews and the updated systematic reviews in Australia, the Consensus Panel agreed to adopt the Canadian recommendations and, apart from some minor changes to the wording of good practice statements, keep the wording of the guidelines, preamble and title of the Canadian Guidelines. The Australian Guidelines provide evidence-informed recommendations for a healthy day (24-h), integrating physical activity, sedentary behaviour (including limits to screen time), and sleep for infants (<1 year), toddlers (1–2 years) and preschoolers (3–5 years).

Conclusions

To our knowledge, this is only the second time the GRADE-ADOLOPMENT approach has been used. Following this approach, the judgments of the Australian Consensus Panel did not differ sufficiently to change the directions and strength of the recommendations and as such, the Canadian recommendations were adopted with very minor alterations. This allowed the Guidelines to be developed much faster and at lower cost. As such, we would recommend the GRADE-ADOLOPMENT approach, especially if a credible set of guidelines, with all supporting materials and developed using a transparent process, is available. Other countries may consider using this approach when developing and/or revising national movement guidelines.

Compliance with the Australian 24-hour movement guidelines for the early years: associations with weight status

Background

For effective public health and surveillance it is important to document the proportion of young children who meet the new Australian Integrated 24 h Movement Guidelines for the Early Years and how these associate with health outcomes. We aimed to (i) assess compliance with the new Integrated 24 h Movement Guidelines for the Early Years in a sample of Australian toddlers; and (ii) ascertain whether compliance with the guidelines associates with weight status.

Methods

The sample comprised 202 toddlers (104 girls) aged 19.74 ± 4.07 months from the GET UP! Study. Participants wore accelerometers (Actigraph GT3X+) for 24 h over 7 consecutive days to assess physical activity, sedentary time and sleep. Parents reported participants’ screen time. Weight and height were measured and body mass index (BMI) z-scores by age and sex were calculated. Analysis of Covariance (ANCOVA) was performed to test differences in BMI z-scores between participants complying with (i) none or any individual guideline, (ii) any combination of meeting two guidelines, and (iii) those who met all three guidelines, adjusting for child age, gender and socioeconomic status.

Results

Only 8.9% of the sample met the overall 24 h movement guidelines. Most of the sample met the physical activity (96.5%) and sleep (79.7%) guidelines but only 11.4% met the sedentary behavior guideline. Average BMI Z-scores did not significantly differ between children who complied with none or any individual guideline, any combination of meeting two guidelines, and those who met all three guidelines (p > 0.05). Although the lack of significant differences, participants who accomplished any combination of two guidelines or all three guidelines appear to have had a lower BMI Z-score than those complying with one of the guidelines or none.

Conclusions

Just under 9% of our sample met the overall Australian 24 h Movement Guidelines for the Early Years. BMI was not associated with the accomplishment of any of the 24-h Movement Guidelines. Strategies to promote adherence to the 24-h movement guidelines in toddlers, particularly for screen time, are necessary, as promoting health-related behaviors in early childhood has the potential to provide children a strong foundation for lifelong physical and mental health.

Electronic supplementary material

The online version of this article (10.1186/s12889-017-4857-8) contains supplementary material, which is available to authorized users.

Wrist Accelerometer Cut Points for Classifying Sedentary Behavior in Children

INTRODUCTION

This study aimed to examine the validity and accuracy of wrist accelerometers for classifying sedentary behavior (SB) in children.

METHODS

Fifty-seven children (5-8 and 9-12 yr) completed an ~170-min protocol, including 15 semistructured activities and transitions. Nine ActiGraph (GT3X+) and two GENEActiv wrist cut points were evaluated. Direct observation was the criterion measure. The accuracy of wrist cut points was compared with that achieved by the ActiGraph hip cut point (≤25 counts per 15 s) and the thigh-mounted activPAL3. Analyses included equivalence testing, Bland-Altman procedures, and area under the receiver operating curve (ROC-AUC).

RESULTS

The most accurate ActiGraph wrist cut points (Kim; vector magnitude, ≤3958 counts per 60 s; vertical axis, ≤1756 counts per 60 s) demonstrated good classification accuracy (ROC-AUC = 0.85-0.86) and accurately estimated SB time in 5-8 yr (equivalence P = 0.02; mean bias = 4.1%, limits of agreement = -20.1% to 28.4%) and 9-12 yr (equivalence P < 0.01; -2.5%, -27.9% to 22.9%). The mean bias of SB time estimates from Kim were smaller than ActiGraph hip (5-8 yr: 15.8%, -5.7% to 37.2%; 9-12 yr: 17.8%, -3.9% to 39.5%) and similar to or smaller than activPAL3 (5-8 yr: 12.6%, -39.8% to 14.7%; 9-12 yr: -1.4%, -13.9% to 11.0%), although classification accuracy was similar to ActiGraph hip (ROC-AUC = 0.85) but lower than activPAL3 (ROC-AUC = 0.92-0.97). Mean bias (5-8 yr: 6.5%, -16.1% to 29.1%; 9-12 yr: 10.5%, -13.6% to 34.6%) for the most accurate GENEActiv wrist cut point (Schaefer: ≤0.19 g) was smaller than ActiGraph hip, and activPAL3 in 5-8 yr, but larger than activPAL3 in 9-12 yr. However, SB time estimates from Schaefer were not equivalent to direct observation (equivalence P > 0.05) and classification accuracy (ROC-AUC = 0.79-0.80) was lower than for ActiGraph hip and activPAL3.

CONCLUSION

The most accurate SB ActiGraph (Kim) and GENEActiv (Schaefer) wrist cut points can be applied in children with similar confidence as the ActiGraph hip cut point (≤25 counts per 15 s), although activPAL3 was generally more accurate.

An internet-supported school physical activity intervention in low socioeconomic status communities: results from the Activity and Motivation in Physical Education (AMPED) cluster randomised controlled trial

Objective

Quality physical education (PE) is the cornerstone of comprehensive school physical activity (PA) promotion programmes. We tested the efficacy of a teacher professional learning intervention, delivered partially via the internet, designed to maximise opportunities for students to be active during PE lessons and enhance adolescents’ motivation towards PE and PA.

Methods

A two-arm cluster randomised controlled trial with teachers and Grade 8 students from secondary schools in low socioeconomic areas of Western Sydney, Australia. The Activity and Motivation in Physical Education (AMPED) intervention for secondary school PE teachers included workshops, online learning, implementation tasks and mentoring sessions. The primary outcome was the proportion of PE lesson time that students spent in moderate-to-vigorous physical activity (MVPA), measured by accelerometers at baseline, postintervention (7–8 months after baseline) and maintenance (14–15 months). Secondary outcomes included observed PE teachers’ behaviour during lessons, students’ leisure-time PA and students’ motivation.

Results

Students (n=1421) from 14 schools completed baseline assessments and were included in linear mixed model analyses. The intervention had positive effects on students’ MVPA during lessons. At postintervention, the adjusted mean difference in the proportion of lesson time spent in MVPA was 5.58% (p<0.001, approximately 4 min/lesson). During the maintenance phase, this effect was 2.64% (p<0.001, approximately 2 min/lesson). The intervention had positive effects on teachers’ behaviour, but did not impact students’ motivation.

Conclusions

AMPED produced modest improvements in MVPA and compares favourably with previous interventions delivered exclusively face-to-face. Online teacher training could help facilitate widespread dissemination of professional learning interventions.

Trial registration number

ACTRN12614000184673.

Moving Forward with Backward Compatibility: Translating Wrist Accelerometer Data

PURPOSE

This study aimed to provide a means for calibrating raw acceleration data from wrist-worn accelerometers in relation to past estimates of children's moderate-to-vigorous physical activity (MVPA) from a range of cut points applied to hip-worn ActiGraph data.

METHODS

This is a secondary analysis of three studies with concurrent 7-d accelerometer wear at the wrist (GENEActiv) and hip (ActiGraph) in 238 children age 9-12 yr. The time spent above acceleration (ENMO) thresholds of 100, 150, 200, 250, 300, 350, and 400 mg from wrist acceleration data (≤5-s epoch) was calculated for comparison with MVPA estimated from widely used children's hip-worn ActiGraph MVPA cut points (Freedson/Trost, 1100 counts per minute; Pate, 1680 counts per minute; Evenson, 2296 counts per minute; Puyau, 3200 counts per minute) with epochs of ≤5, 15, and 60 s.

RESULTS

The optimal ENMO thresholds for alignment with MVPA estimates from ActiGraph cut points determined from 70% of the sample and cross validated with the remaining 30% were as follows: Freedson/Trost = ENMO 150+ mg, irrespective of ActiGraph epoch (intraclass correlation [ICC] ≥ 0.65); Pate = ENMO 200+ mg, irrespective of ActiGraph epoch (ICC ≥ 0.67); Evenson = ENMO 250+ mg for ≤5- and 15-s epochs (ICC ≥ 0.69) and ENMO 300+ mg for 60-s epochs (ICC = 0.73); Puyau = ENMO 300+ mg for ≤5-s epochs (ICC = 0.73), ENMO 350+ mg for 15-s epochs (ICC = 0.73), and ENMO 400+ mg for 60-s epochs (ICC = 0.65). Agreement was robust with cross-validation ICC = 0.62-0.71 and means within ∣7.8∣% ± 4.9% of MVPA estimates from ActiGraph cut points, except Puyau 60-s epochs (ICC = 0.42).

CONCLUSION

Incremental ENMO thresholds enable children's acceleration data measured at the wrist to be simply and directly compared, at a group level, with past estimates of MVPA from hip-worn ActiGraphs across a range of cut points.

Acute effects of reducing sitting time in adolescents: a randomized cross-over study

BACKGROUND

Levels of sitting among adolescents are high, especially during the school day. The acute cognitive and health consequences associated with prolonged sitting are poorly understood in adolescents. This randomized crossover design study examined the acute effects of a simulated school day with reduced sitting or usual sitting on adolescents' cognitive function and cardiometabolic biomarkers.

METHODS

Eighteen healthy school aged adolescents were recruited from the community to the study (11 males; 7 females; mean age [SD] = 13.5 ± 0.9 years). Two protocols were developed to simulate an adolescent school day, the amount of time spent sitting was manipulated reflecting: a 'typical' day (65% of the time spent sitting with two sitting bouts sitting >20 min) and a 'reduced sitting' day (adolescents sat for 50% less time with no bouts of sitting >20 mins). The order that participants were exposed to each condition was randomized (via random number generator). Participants were not fully blinded as they could observe the difference between conditions. Energy intake and moderate to vigorous physical activity (MVPA) were standardized for both conditions and monitored for 48 h post-condition for compensatory effects. Cognitive (working memory) and cardiometabolic outcomes (lipids, glucose, insulin, IL-6, apo-A1, apo-B, blood pressure,) were assessed pre and post for both conditions, BMI and body fat were assessed on the morning of the intervention. Data were analyzed using linear mixed models. Standardised effect sizes were calculated.

RESULTS

Compared with the typical school day, the reduced sitting day demonstrated significant positive effects for apoB/apoA-1 ratio (adjusted difference ± SD) -0.02 ± 0.03; P = 0.03; effect size [Cohen's d] = -0.67. Findings for total cholesterol -0.19 ± 0.27; P = 0.28; d = -0.71; HDL cholesterol -0.23 ± 0.50; P = 0.12 d = -0.66; and total cholesterol/HDL ratio 0.25 ± 0.53; P = 0.25; d = 0.51 and for cognition 0.64 ± 0.15; P = 0.15; d = 0.54 were non-significant. There were no compensatory changes in participant energy expenditure or energy intake for 48 h post intervention.

CONCLUSION

Reducing school day sitting time in adolescents' resulted in significant improvements in apoB/apoA-1 ratio with medium effect sizes for total cholesterol, HDL cholesterol and total cholesterol/HDL ratio. Cognitive function results showed the equivalent of a 6 month improvement in effective mental-attentional capacity.

TRIAL REGISTRATION

The trial was registered as a clinical trial with the Australian and New Zealand Clinical Trials Registry ( ACTRN12614001064695 ) on the 3rd of October 2014 - registered retrospectively.

The Preschool Activity, Technology, Health, Adiposity, Behaviour and Cognition (PATH-ABC) cohort study: rationale and design

BACKGROUND

Prevalence estimates internationally suggest that many preschool-aged children (3-5 years) are insufficiently physically active and engage in high levels of screen-based entertainment. Early childhood is the developmental period for which we know the least about the effects of physical activity on development and health. Likewise, rapid technological advancements in mobile electronic media have made screen-based forms of entertainment for young children ubiquitous, and research demonstrating the impacts on cognition, psychosocial well-being, and health has lagged behind the rate of adoption of these technologies. The purpose of the Preschool Activity, Technology, Health, Adiposity, Behaviour and Cognition (PATH-ABC) study is to investigate if physical activity and screen-based entertainment are independently associated with cognitive and psychosocial development, and health outcomes in young children, and if so, how much and which types of these behaviours might be most influential.

METHODS

The PATH-ABC study is a prospective cohort, aiming to recruit 430 3-5 year-old children. Children are recruited through and complete initial assessments at their Early Childhood Education and Care (ECEC) centre, and then 12-months later at their centre or school. Direct assessments are made of children's habitual physical activity using accelerometry, cognitive (executive function) and language development (expressive vocabulary), psychosocial development (emotional understanding, Theory of Mind, empathy, and heart rate variability), adiposity (body mass index and waist circumference), and cardiovascular health (blood pressure and retinal micro- vasculature). Educators report on children's psychological strengths and difficulties and self-regulation. Parents report on children's habitual use of electronic media and other child, parent and household characteristics.

DISCUSSION

The PATH-ABC study aims to provide evidence to enhance understanding of how much and which types of physical activity and screen-based media influence development and health in preschool-aged children. This information would benefit parents, educators, health professionals and governments seeking to develop strategies and policies to give young children the best start in life by promoting healthy levels of physical activity and electronic media use.

Sedentary time, physical activity and compliance with IOM recommendations in young children at childcare

The aim of this study was to report patterns of sitting, standing and physical activity (PA) and compliance with Institute of Medicine (IOM) recommendations for sedentary behavior (SB) and PA among children aged 1 to 5 years at childcare, and examine sociodemographic variations.

Sitting, standing and PA time was assessed using an activPAL inclinometer over a period of 1 to 5 days in 301 children (49% boys; mean age = 3.7 ± 1.0 years) across 11 childcare services in Illawarra, NSW, Australia. Breaks and bouts of sitting and standing were calculated and categorized. Height and weight were assessed and parents completed a demographic survey. Differences by sex, age category (< 3 vs ≥ 3 years), weight status and SES were examined.

Children spent 48.4% of their time at childcare sitting, 32.5% standing, and 19.1% in PA. Boys spent significantly more time in PA compared to girls (20.8% vs 17.7%; P = 0.003). Toddlers (< 3 years) spent significantly more time in PA compared to preschoolers (≥ 3 years) (22.2% vs 18.3%; P < 0.001). Children who were underweight spent significantly more time sitting compared with their overweight peers (52.4% vs 46.8%; P = 0.003). 56% and 16% of children met the IOM SB and PA recommendations, respectively. Girls (odds ratio [OR]; 95%CI = 0.26; 0.13 to 0.55) and preschoolers (0.16; 0.07 to 0.38) were less likely to meet the IOM PA recommendation compared to boys and toddlers. Young children spent ~ 50% of their time at childcare sitting. Girls and preschoolers sit more and are less likely to meet PA recommendations, making them important groups to target in future interventions.

•

Use of an objective and direct measure to assess sitting, standing and PA.

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Assessment of compliance with the IOM recommendation for SB and PA in childcare.

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Young children spent almost half of their day at childcare sitting.

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Girls and preschoolers sit more and are less likely to meet PA recommendations.

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Strategies to break-up sitting time with more standing and LMVPA are warranted.

The theory of expanded, extended, and enhanced opportunities for youth physical activity promotion

BACKGROUND

Physical activity interventions targeting children and adolescents (≤18 years) often focus on complex intra- and inter-personal behavioral constructs, social-ecological frameworks, or some combination of both. Recently published meta-analytical reviews and large-scale randomized controlled trials have demonstrated that these intervention approaches have largely produced minimal or no improvements in young people's physical activity levels.

DISCUSSION

In this paper, we propose that the main reason for previous studies' limited effects is that fundamental mechanisms that lead to change in youth physical activity have often been overlooked or misunderstood. Evidence from observational and experimental studies is presented to support the development of a new theory positing that the primary mechanisms of change in many youth physical activity interventions are approaches that fall into one of the following three categories: (a) the expansion of opportunities for youth to be active by the inclusion of a new occasion to be active, (b) the extension of an existing physical activity opportunity by increasing the amount of time allocated for that opportunity, and/or (c) the enhancement of existing physical activity opportunities through strategies designed to increase physical activity above routine practice. Their application and considerations for intervention design and interpretation are presented. The utility of these mechanisms, referred to as the Theory of Expanded, Extended, and Enhanced Opportunities (TEO), is demonstrated in their parsimony, logical appeal, support with empirical evidence, and the direct and immediate application to numerous settings and contexts. The TEO offers a new way to understand youth physical activity behaviors and provides a common taxonomy by which interventionists can identify appropriate targets for interventions across different settings and contexts. We believe the formalization of the TEO concepts will propel them to the forefront in the design of future intervention studies and through their use, lead to a greater impact on youth activity behaviors than what has been demonstrated in previous studies.

"GET-UP" study rationale and protocol: a cluster randomised controlled trial to evaluate the effects of reduced sitting on toddlers' cognitive development

BACKGROUND

The educational and cognitive differences associated with low socioeconomic status begin early in life and tend to persist throughout life. Coupled with the finding that levels of sedentary time are negatively associated with cognitive development, and time spent active tends to be lower in disadvantaged circumstances, this highlights the need for interventions that reduce the amount of time children spend sitting and sedentary during childcare. The proposed study aims to assess the effects of reducing sitting time during Early Childhood Education and Care (ECEC) services on cognitive development in toddlers from low socio-economic families.

METHODS/DESIGN

We will implement a 12-months 2-arm parallel group cluster randomised controlled trial (RCT) with Australian toddlers, aged 12 to 26 months at baseline. Educators from the ECEC services allocated to the intervention group will receive professional development on how to reduce sitting time while children attend ECEC. Participants' cognitive development will be assessed as a primary outcome, at baseline and post-intervention, using the cognitive sub-test from the Bayley Scales of Infant and Toddler Development.

DISCUSSION

This trial has the potential to inform programs and policies designed to optimize developmental and health outcomes in toddlers, specifically in those from disadvantaged backgrounds.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12616000471482 , 11/04/2016, retrospectively registered.

Flexibility is associated with motor competence in schoolchildren

Available data on the associations between motor competence (MC) and flexibility are limited and result inconclusive. This study aims to examine the relationship between flexibility and MC in children. The sample comprised 596 Portuguese children (47.1% girls) aged 9.7 ± 0.6 years. Motor competence was evaluated with the body coordination test, Körperkoordination Test für Kinder. Cardiorespiratory fitness (20-m shuttle run), muscular strength (curl-up and push-up tests), and flexibility (back-saver sit and reach and trunk-lift tests) were evaluated using the Fitnessgram Test Battery. Z-scores by age and gender for the physical fitness tests were constructed. Analysis of variance and regression analysis were performed. Participants in the healthy zone groups of both flexibility tests exhibited significantly better scores of MC than the participants under the healthy zone (P < 0.001). Back-saver sit and reach and trunk-lift Z-scores, either individually or as a sum, were significant predictors of MC (P < 0.05 for all) after adjustments for the other physical fitness components, age, body mass index, and socioeconomic status, in both genders. Our findings highlight the importance of promoting and developing flexibility, as well as the other health-related physical fitness components in schoolchildren to reach adequate levels of MC.

Validation of thigh-based accelerometer estimates of postural allocation in 5-12 year-olds

OBJECTIVES

To validate activPAL3™ (AP3) for classifying postural allocation, estimating time spent in postures and examining the number of breaks in sedentary behaviour (SB) in 5-12 year-olds.

DESIGN

Laboratory-based validation study.

METHODS

Fifty-seven children completed 15 sedentary, light- and moderate-to-vigorous intensity activities. Direct observation (DO) was used as the criterion measure. The accuracy of AP3 was examined using a confusion matrix, equivalence testing, Bland-Altman procedures and a paired t-test for 5-8y and 9-12y.

RESULTS

Sensitivity of AP3 was 86.8%, 82.5% and 85.3% for sitting/lying, standing, and stepping, respectively, in 5-8y and 95.3%, 81.5% and 85.1%, respectively, in 9-12y. Time estimates of AP3 were equivalent to DO for sitting/lying in 9-12y and stepping in all ages, but not for sitting/lying in 5-12y and standing in all ages. Underestimation of sitting/lying time was smaller in 9-12y (1.4%, limits of agreement [LoA]: -13.8 to 11.1%) compared to 5-8y (12.6%, LoA: -39.8 to 14.7%). Underestimation for stepping time was small (5-8y: 6.5%, LoA: -18.3 to 5.3%; 9-12y: 7.6%, LoA: -16.8 to 1.6%). Considerable overestimation was found for standing (5-8y: 36.8%, LoA: -16.3 to 89.8%; 9-12y: 19.3%, LoA: -1.6 to 36.9%). SB breaks were significantly overestimated (5-8y: 53.2%, 9-12y: 28.3%, p<0.001).

CONCLUSIONS

AP3 showed acceptable accuracy for classifying postures, however estimates of time spent standing were consistently overestimated and individual error was considerable. Estimates of sitting/lying were more accurate for 9-12y. Stepping time was accurately estimated for all ages. SB breaks were significantly overestimated, although the absolute difference was larger in 5-8y. Surveillance applications of AP3 would be acceptable, however, individual level applications might be less accurate.

Scaling-up an efficacious school-based physical activity intervention: Study protocol for the 'Internet-based Professional Learning to help teachers support Activity in Youth' (iPLAY) cluster randomized controlled trial and scale-up implementation evaluation

Background

Despite the health benefits of regular physical activity, most children are insufficiently active. Schools are ideally placed to promote physical activity; however, many do not provide children with sufficient in-school activity or ensure they have the skills and motivation to be active beyond the school setting. The aim of this project is to modify, scale up and evaluate the effectiveness of an intervention previously shown to be efficacious in improving children’s physical activity, fundamental movement skills and cardiorespiratory fitness. The ‘Internet-based Professional Learning to help teachers support Activity in Youth’ (iPLAY) study will focus largely on online delivery to enhance translational capacity.

Methods/Design

The intervention will be implemented at school and teacher levels, and will include six components: (i) quality physical education and school sport, (ii) classroom movement breaks, (iii) physically active homework, (iv) active playgrounds, (v) community physical activity links and (vi) parent/caregiver engagement. Experienced physical education teachers will deliver professional learning workshops and follow-up, individualized mentoring to primary teachers (i.e., Kindergarten – Year 6). These activities will be supported by online learning and resources. Teachers will then deliver the iPLAY intervention components in their schools. We will evaluate iPLAY in two complementary studies in primary schools across New South Wales (NSW), Australia. A cluster randomized controlled trial (RCT), involving a representative sample of 20 schools within NSW (1:1 allocation at the school level to intervention and attention control conditions), will assess effectiveness and cost-effectiveness at 12 and 24 months. Students’ cardiorespiratory fitness will be the primary outcome in this trial. Key secondary outcomes will include students’ moderate-to-vigorous physical activity (via accelerometers), fundamental movement skill proficiency, enjoyment of physical education and sport, cognitive control, performance on standardized tests of numeracy and literacy, and cost-effectiveness. A scale-up implementation study guided by the RE-AIM framework will evaluate the reach, effectiveness, adoption, implementation, and maintenance of the intervention when delivered in 160 primary schools in urban and regional areas of NSW.

Discussion

This project will provide the evidence and a framework for government to guide physical activity promotion throughout NSW primary schools and a potential model for adoption in other states and countries.

Trial registration

Australia and New Zealand Clinical Trials Registry (ACTRN12616000731493). Date of registration: June 3, 2016.

Validation of the SenseWear Mini activity monitor in 5-12-year-old children

OBJECTIVES

This study aimed to validate SenseWear Mini software algorithm versions 2.2 (SW2.2) and 5.2 (SW5.2) for estimating energy expenditure (EE) in children.

DESIGN

Laboratory-based validation study.

METHODS

57 children aged 5-12 y completed a protocol involving 15 semi-structured sedentary (SED), light-intensity (LPA), and moderate- to vigorous-intensity (MVPA) physical activities. EE was estimated using portable indirect calorimetry (IC). The accuracy of EE estimates (kcal·min^-1) from SW2.2 and SW5.2 were examined at the group level and individual level using the mean absolute percentage error (MAPE), Bland-Altman plots and equivalence testing.

RESULTS

MAPE values were lower for SW5.2 (30.1±10.7%) than for SW2.2 (44.0±6.2%). Although mean differences for SW5.2 were smaller than for SW2.2 during SED (-0.23±0.22 vs. -0.61±0.20kcal·min^-1), LPA (-0.69±0.76 vs. -1.07±0.46kcal·min^-1) and MVPA (-2.22±1.15 vs. -2.57±1.15kcal·min^-1), limits of agreement did not decrease for the updated algorithms. For all activities, SW2.2 and SW5.2 were not equivalent to IC (p>0.05). Errors increased with increasing intensity.

CONCLUSION

The current SenseWear Mini algorithms SW5.2 underestimated EE. The overall improved accuracy for SW5.2 was not accompanied with improved accuracy at the individual level and EE estimates were not equivalent to IC.

Objectively measured sedentary behaviour and health and development in children and adolescents: systematic review and meta-analysis

Sedentary behaviour has emerged as a unique determinant of health in adults. Studies in children and adolescents have been less consistent. We reviewed the evidence to determine if the total volume and patterns (i.e. breaks and bouts) of objectively measured sedentary behaviour were associated with adverse health outcomes in young people, independent of moderate-intensity to vigorous-intensity physical activity. Four electronic databases (EMBASE MEDLINE, Ovid EMBASE, PubMed and Scopus) were searched (up to 12 November 2015) to retrieve studies among 2- to 18-year-olds, which used cross-sectional, longitudinal or experimental designs, and examined associations with health outcomes (adiposity, cardio-metabolic, fitness, respiratory, bone/musculoskeletal, psychosocial, cognition/academic achievement, gross motor development and other outcomes). Based on 88 eligible observational studies, level of evidence grading and quantitative meta-analyses indicated that there is limited available evidence that the total volume or patterns of sedentary behaviour are associated with health in children and adolescents when accounting for moderate-intensity to vigorous-intensity physical activity or focusing on studies with low risk of bias. Quality evidence from studies with robust designs and methods, objective measures of sitting, examining associations for various health outcomes, is needed to better understand if the overall volume or patterns of sedentary behaviour are independent determinants of health in children and adolescents.

An Internet-supported Physical Activity Intervention Delivered in Secondary Schools Located in Low Socio-economic Status Communities: Study Protocol for the Activity and Motivation in Physical Education (AMPED) Cluster Randomized Controlled Trial

Background

School-based physical education is an important public health initiative as it has the potential to provide students with regular opportunities to participate in moderate-to-vigorous physical activity (MVPA). Unfortunately, in many physical education lessons students do not engage in sufficient MVPA to achieve health benefits. In this trial we will test the efficacy of a teacher professional development intervention, delivered partially via the Internet, on secondary school students’ MVPA during physical education lessons. Teaching strategies covered in this training are designed to (i) maximize opportunities for students to be physically active during lessons and (ii) enhance students’ autonomous motivation towards physical activity.

Method

A two-arm cluster randomized controlled trial with allocation at the school level (intervention vs. usual care control). Teachers and Year 8 students in government-funded secondary schools in low socio-economic areas of the Western Sydney region of Australia will be eligible to participate. During the main portion of the intervention (6 months), teachers will participate in two workshops and complete two implementation tasks at their school. Implementation tasks will involve video-based self-reflection via the project’s Web 2.0 platform and an individualized feedback meeting with a project mentor. Each intervention school will also complete two group peer-mentoring sessions at their school (one per term) in which they will discuss implementation with members of their school physical education staff. In the booster period (3 months), teachers will complete a half-day workshop at their school, plus one online implementation task, and a group mentoring session at their school. Throughout the entire intervention period (main intervention plus booster period), teachers will have access to online resources. Data collection will include baseline, post-intervention (7–8 months after baseline) and maintenance phase (14–15 months after baseline) assessments. Research assistants blinded to group allocation will collect all data. The primary outcome will be the proportion of physical education lesson time that students spend in MVPA. Secondary outcomes will include leisure-time physical activity, subjective well-being, and motivation towards physical activity.

Discussion

The provision of an online training platform for teachers could help facilitate more widespread dissemination of evidence-based interventions compared with programs that rely exclusively on face-to-face training.

Trial registration

Australia and New Zealand Clinical Trials Registry-ACTRN12614000184673. Registration date: February 19, 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2583-7) contains supplementary material, which is available to authorized users.