Simple Method for the Objective Activity Type Assessment with Preschoolers, Children and Adolescents

Effectiveness of a Preschool Motor Skill Intervention on Body Mass Index and Movement Behavior: 6-, 18-, and 30-Month Findings From a Cluster Randomized Controlled Trial

PURPOSE

To study the effectiveness of a preschool staff-delivered motor skills intervention on body composition and physical activity over a 2.5-year time frame.

METHODS

In this pragmatic parallel cluster randomized controlled trial (16 preschools), outcome data were collected after 6 (body composition only), 18, and 30 months of intervention. The main physical activity outcomes were accelerometer behavior measures summarizing the total percentage of child daily movement (walk, run, cycle, and standing that included minor movements) and preschool movement during preschool attendance. To estimate between-group mean differences in outcomes, mixed-linear regression analyses including baseline value of the selected outcome and a treatment × time interaction term as a fixed effect were applied. In addition, the baseline preschool and child were included as a random effect.

RESULTS

For body mass index, a total of 437 children (90%) had at least one valid baseline and one follow-up assessment. The corresponding numbers for preschool movement and daily movement were 163 (55%) and 146 (49%), respectively. No significant between-group mean difference was identified for body mass index, waist-to-height ratio, or any physical activity outcomes.

CONCLUSION

Overall, this preschool motor skills intervention had no effect on either child anthropometry or physical activity, consistent with previous studies.

Energy Expenditure Prediction from Accelerometry Data Using Long Short-Term Memory Recurrent Neural Networks

The accurate estimation of energy expenditure from simple objective accelerometry measurements provides a valuable method for investigating the effect of physical activity (PA) interventions or population surveillance. Methods have been evaluated previously, but none utilize the temporal aspects of the accelerometry data. In this study, we investigated the energy expenditure prediction from acceleration measured at the subjects' hip, wrist, thigh, and back using recurrent neural networks utilizing temporal elements of the data. The acceleration was measured in children (N = 33) performing a standardized activity protocol in their natural environment. The energy expenditure was modelled using Multiple Linear Regression (MLR), stacked long short-term memory (LSTM) networks, and combined convolutional neural networks (CNN) and LSTM. The correlation and mean absolute percentage error (MAPE) were 0.76 and 19.9% for the MLR, 0.882 and 0.879 and 14.22% for the LSTM, and, with the combined LSTM-CNN, the best performance of 0.883 and 13.9% was achieved. The prediction error for vigorous intensities was significantly different (p < 0.01) from those of the other intensity domains: sedentary, light, and moderate. Utilizing the temporal elements of movement significantly improves energy expenditure prediction accuracy compared to other conventional approaches, but the prediction error for vigorous intensities requires further investigation.

Study protocol for the Screen-Free Time with Friends Feasibility Trial

BACKGROUND

Children are spending less leisure time with their friends in person and an increasing amount of time with digital screens. These changes may negatively affect children's physical and mental health. The Screen-Free Time with Friends Feasibility Trial will test the feasibility, including acceptability and compliance, of an intervention designed to reduce screen media usage and encourage physical interaction with friends during leisure time in 9-11-year-old children.

METHODS

A non-randomized single-group feasibility trial will be conducted from March to October 2023 including approximately 75 children (aged 9-11 years) and 75 parents (at least 1 per child) from 3 different schools recruited from 3 different municipalities in Denmark. The Screen-Free Time with Friends intervention is a multicomponent intervention targeting families, afterschool clubs, and local communities. It has been developed using a systematic process guided by the Medical Research Council UK's framework for developing and evaluating complex interventions. With a systems perspective in mind, the intervention and implementation approach has been designed to facilitate adaptation to the specific needs of diverse local communities while maintaining the core components of the intervention. Feasibility and acceptability of the intervention will be assessed during the intervention using process evaluation inspired by the RE-AIM framework including questionnaires and interviews with the municipality project managers, research team members, local ambassadors and stakeholders, parents and school, and afterschool club personnel. In addition, participation, recruitment, retention rate, and compliance to the outcome measurements will be investigated and presented.

DISCUSSION

The trial will investigate the feasibility and acceptability of the Screen-Free Time with Friends intervention, the recruitment strategy, and the planned outcome measurements. This feasibility study will investigate necessary refinements before the implementation of the intervention program in a larger cluster randomized controlled trial to evaluate its impact.

TRIAL REGISTRATION

CLINICALTRIALS

gov, ID: NCT05480085. Registered 29 July 2022. https://clinicaltrials.gov/ct2/show/NCT05480085?cond=Screen+free+time+with+friends&draw=2&rank=1.

Sensitivity and specificity of measuring children's free-living cycling with a thigh-worn Fibion® accelerometer

Objective

Cycling is an important part of children's active travel, but its measurement using accelerometry is a challenge. The aim of the present study was to evaluate physical activity duration and intensity, and sensitivity and specificity of free-living cycling measured with a thigh-worn accelerometer.

Methods

Participants were 160 children (44 boys) aged 11.5 ± 0.9 years who wore a triaxial Fibion® accelerometer on right thigh for 8 days, 24 h per day, and reported start time and duration of all cycling, walking and car trips to a travel log. Linear mixed effects models were used to predict and compare Fibion-measured activity and moderate-to-vigorous activity duration, cycling duration and metabolic equivalents (METs) between the travel types. Sensitivity and specificity of cycling bouts during cycling trips as compared to walking and car trips was also evaluated.

Results

Children reported a total of 1,049 cycling trips (mean 7.08 ± 4.58 trips per child), 379 walking trips (3.08 ± 2.81) and 716 car trips (4.79 ± 3.96). There was no difference in activity and moderate-to-vigorous activity duration (p > .105), a lower cycling duration (-1.83 min, p < .001), and a higher MET-level (0.95, p < .001) during walking trips as compared to cycling trips. Both activity (-4.54 min, p < .001), moderate-to-vigorous activity (-3.60 min, p < .001), cycling duration (-1.74 min, p < .001) and MET-level (-0.99, p < .001) were lower during car trips as compared to cycling trips. Fibion showed the sensitivity of 72.2% and specificity of 81.9% for measuring cycling activity type during the reported cycling trips as compared to walking and car trips when the minimum required duration for cycling was less than 29 s.

Conclusions

The thigh-worn Fibion® accelerometer measured a greater duration of cycling, a lower MET-level, and a similar duration of total activity and moderate-to-vigorous activity during free-living cycling trips as compared to walking trips, suggesting it can be used to measure free-living cycling activity and moderate-to-vigorous activity duration in 10-12-year-old children.

Systematic review of accelerometer-based methods for 24-h physical behavior assessment in young children (0-5 years old)

BACKGROUND

Accurate accelerometer-based methods are required for assessment of 24-h physical behavior in young children. We aimed to summarize evidence on measurement properties of accelerometer-based methods for assessing 24-h physical behavior in young children.

METHODS

We searched PubMed (MEDLINE) up to June 2021 for studies evaluating reliability or validity of accelerometer-based methods for assessing physical activity (PA), sedentary behavior (SB), or sleep in 0-5-year-olds. Studies using a subjective comparison measure or an accelerometer-based device that did not directly output time series data were excluded. We developed a Checklist for Assessing the Methodological Quality of studies using Accelerometer-based Methods (CAMQAM) inspired by COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN).

RESULTS

Sixty-two studies were included, examining conventional cut-point-based methods or multi-parameter methods. For infants (0-12 months), several multi-parameter methods proved valid for classifying SB and PA. From three months of age, methods were valid for identifying sleep. In toddlers (1-3 years), cut-points appeared valid for distinguishing SB and light PA (LPA) from moderate-to-vigorous PA (MVPA). One multi-parameter method distinguished toddler specific SB. For sleep, no studies were found in toddlers. In preschoolers (3-5 years), valid hip and wrist cut-points for assessing SB, LPA, MVPA, and wrist cut-points for sleep were identified. Several multi-parameter methods proved valid for identifying SB, LPA, and MVPA, and sleep. Despite promising results of multi-parameter methods, few models were open-source. While most studies used a single device or axis to measure physical behavior, more promising results were found when combining data derived from different sensor placements or multiple axes.

CONCLUSIONS

Up to age three, valid cut-points to assess 24-h physical behavior were lacking, while multi-parameter methods proved valid for distinguishing some waking behaviors. For preschoolers, valid cut-points and algorithms were identified for all physical behaviors. Overall, we recommend more high-quality studies evaluating 24-h accelerometer data from multiple sensor placements and axes for physical behavior assessment. Standardized protocols focusing on including well-defined physical behaviors in different settings representative for children's developmental stage are required. Using our CAMQAM checklist may further improve methodological study quality.

PROSPERO REGISTRATION NUMBER

CRD42020184751.

Effects of Limiting Recreational Screen Media Use on Physical Activity and Sleep in Families With Children: A Cluster Randomized Clinical Trial

IMPORTANCE

Children and adults spend large amounts of their leisure time using screen media, which may affect their health and behavior.

OBJECTIVE

To investigate the effect of reducing household recreational screen media use on physical activity and sleep in children and adults.

DESIGN, SETTING, AND PARTICIPANTS

This was a cluster randomized clinical trial with a 2-week follow-up. Enrollment began on June 6, 2019, and ended on March 30, 2021. This study included a population-based sample from 10 Danish municipalities. A total of 89 families (181 children and 164 adults) were recruited based on a population-based survey on screen media habits in families with children. To be eligible, the responding parent had to list self-reported recreational screen use greater than the 40th percentile of recreational screen time use in the source population (>2.4 hours per day). In addition, the parent had to be full-time employed (with no regular night shifts) or enrolled in full-time education.

INTERVENTIONS

Families were randomly assigned to the screen media reduction intervention (45 families, 86 children, 82 adults) designed to ensure participant compliance to a maximum use of screen media (≤3 hours per week) for a 2-week period. Families randomly assigned to the control group (44 families, 95 children, 82 adults) were instructed to carry on as usual.

MAIN OUTCOMES AND MEASURES

The primary outcome was between-group difference in leisure nonsedentary activity (in minutes per day) measured by combined thigh and waist accelerometry. Secondary outcomes included other physical activity and sleep parameters measured by single-channel electroencephalography.

RESULTS

Among the 89 randomized families (intervention group [45 families]: 86 children; mean [SD] age, 8.6 [2.7] years; 44 boys [51%]; 42 girls [49%]; control group [44 families]: 95 children, mean [SD] age, 9.5 [2.5] years; 38 boys [40%]; 57 girls [60%]), 157 children (87%) had complete data on the primary outcome. Eighty-three children (97%) in the intervention group were compliant to the screen use reduction during the intervention. The mean (SD) change in leisure nonsedentary activity in the intervention group was 44.8 (63.5) minutes per day and in the control group was 1.0 (55.1) minute per day (intention-to-treat between-group mean difference, 45.8 minutes per day; 95% CI, 27.9-63.6 minutes per day; P < .001). No significant between-group mean differences were observed between intervention and control for the electroencephalography-based sleep outcomes.

CONCLUSIONS AND RELEVANCE

In this cluster randomized clinical trial, a recreational screen media reduction intervention resulted in a substantial increase in children's engagement in physical activity. The large effect size suggests that the high levels of recreational screen media use seen in many children should be a public health concern.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04098913.

Associations between children's physical literacy and well-being: is physical activity a mediator?

Background

Physical literacy (PL) is a multi-dimensional concept that provides a holistic understanding of movement and physical activity. PL contains an affective, a physical, and a cognitive domain, which together lay the foundation for the individual’s capacity and the tendency for participating in physical activities currently and throughout life. PL is increasingly regarded as a ‘cause of the causes’ to health promotion. Cross-sectional studies have shown associations between children’s PL, physical activity behaviours, and well-being. This study aims to examine the associations between Danish children’s PL and their physical and psychosocial well-being and whether the associations are mediated by moderate- to vigorous intensity physical activity (MVPA).

Methods

Cross-sectional data from Danish schoolchildren aged 7–13 years were collected in Jan-Dec 2020 in the Danish Assessment of Physical Literacy (DAPL) project. PL was assessed with the DAPL which measures the affective, cognitive, and physical domains of PL. MVPA (min/day) was measured with accelerometers (Axivity), psychosocial well-being was measured with The Strengths and Difficulties Questionnaire, and physical well-being was measured with the KIDSCREEN questionnaire. Structural equation models were constructed with PL and MVPA as predictors of physical well-being and four aspects of psychosocial well-being.

Results

A positive moderate association between PL and physical well-being, partly mediated by MVPA was observed. PL was positively associated with the positive aspects of psychosocial well-being and negatively associated with the negative aspects (behaviour problems). None of the associations between PL and aspects of psychosocial well-being were mediated by MVPA.

Conclusions

The study contributes to evidence on the link between PL, physical activity, and health outcomes. The study found beneficial relations between PL and physical and psychosocial well-being. MVPA mediated part of the relationship between PL and physical well-being but not psychosocial well-being.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13517-x.

Feasibility of two screen media reduction interventions: Results from the SCREENS pilot trial

Background

Advancements in screen media devices has transformed the way families engage with screen media. Although these modern devices offer many opportunities, e.g. communication and research online, an in-depth understanding of how these devices affect our health, is lacking. Before a definite randomized controlled trial, the SCREENS pilot study was conducted to assess compliance to and feasibility of two interventions, a measurement protocol, and a survey-based recruitment strategy. Also, the potential of the interventions to impact leisure time spent non-sedentary in children six-to-ten years of age was explored.

Methods

Families (N = 12) were recruited through a population-based survey sent out in October of 2018 to adults (N = 1,675) in the Municipality of Middelfart, Denmark. Families were randomized to one of two two-week interventions; an Evening Restriction intervention (no screen media use after six pm) and a General Restrict intervention (limit entertainment-based screen media to three hours/week/person). Intervention compliance was assessed objectively by measuring household TV usage, smartphone and tablet activity via an application, and via screen media diaries. During baseline and follow-up, as part of larger protocol, family members wore two triaxial accelerometers for seven consecutive days. The potential of the interventions to impact non-sedentary time was explored based on means and standard errors (SEs).

Results

Despite almost 85% and 75% reductions in leisure screen media use 0% and 50% of families were compliant in the Evening Restrict group and General Restrict group, respectively, based on strict a priori criteria. Participant feedback indicated that the General Restrict intervention generally was feasibly. Compliance to the accelerometry wear protocol was high (median non-wear was <1 hour/week). Moreover, the recruitment strategy was implemented and was feasible. The General restrict intervention might increase children’s non-sedentary time (mean (SE): 36.6 (23) min/day, N = 6).

Conclusions

The General Restriction intervention, the accelerometer wear protocol and recruitment strategy, appeared feasible.

Trial registration

NCT03788525 at https://clinicaltrials.gov [Retrospectively registered; 27^th of December, 2018].

Exploring implementation of a nationwide requirement to increase physical activity in the curriculum in Danish public schools: a mixed methods study

BACKGROUND

In 2014, the Danish Government introduced a wide-ranging school reform that applied to all public schools in Denmark. A distinctive feature of the reform was that it became mandatory to implement an average of 45 min of daily physical activity within the curriculum. Using the RE-AIM framework as an evaluation tool, the objective of the current study was to evaluate the reach, effectiveness, adoption, implementation, and maintenance of mandatory physical activity within the curriculum at ten Danish schools.

METHODS

A complementary mixed-methods approach using accelerometers, questionnaires, and semi-structured interviews was conducted. A total of 10 schools were invited to participate, including 846 students, 76 teachers, and 10 school managers on various levels. Students were invited to wear an accelerometer for seven consecutive days. Teachers were invited to participate in a questionnaire, and school managers were encouraged to take part in a semi-structured interview.

RESULTS

Results showed that, on average, 45.2% of the students were active at least 45 min daily within the curriculum. Teacher and school management interest in physical activity, competencies development, and shared decision-making were identified as central factors for adoption of the requirement. Scheduling physical activity within scheduels and collaborations with external parties were found to influence implementation. Finally, internal coordination, motivated school staff, and school management priority were identified as central factors for maintenance.

CONCLUSIONS

This study provides an evaluation on a nationwide physical activity requirement in Danish public schools. When introducing a wide-ranging nation-wide requirement on physical activity within the curriculum, school managers need to prioritize and support the implementation process. Teachers need to be involved in the decision processes in order to ensure motivation and local ownership. The study also highlights the benefits of an internal coordinator as well as development of a shared strategy among schools, municipalities, and other stakeholders in order to succeed with the implementation.

Bidirectional associations between sedentary time and sleep duration among 12- to 14-year-old adolescents

Background

The aim of this study was to investigate bidirectional associations between (prolonged) sitting time and sleep duration in 12- to 14-year-old adolescents using a between-subjects and within-subjects analyses approach.

Methods

Observational data were used from 108 adolescents (53% girls; mean age 12.9 (SD 0.7) years) from six schools in Flanders, Belgium. The Axivity AX3 triaxial accelerometer, worn on the thigh, was used to assess daily total sitting time and daily time spent in sedentary bouts of ≥30 min (as a proxy for prolonged sitting time). The Fitbit Charge 3 was used to assess nightly sleep duration. Both monitors were worn on schooldays only (ranging from 4 to 5 days). Linear mixed models were conducted to analyse the associations, resulting in four models. In each model, the independent variable (sleep duration, sitting time or prolonged sitting time) was included as within- as well as between-subjects factor.

Results

Within-subjects analyses showed that when the adolescents sat more and when the adolescents spent more time sitting in bouts of ≥30 min than they usually did on a given day, they slept less during the following night (p = 0.01 and p = 0.05 (borderline significant), respectively). These associations were not significant in the other direction. Between-subjects analyses showed that adolescents who slept more on average, spent less time sitting (p = 0.006) and less time sitting in bouts of ≥30 min (p = 0.004) compared with adolescents who slept less on average. Conversely, adolescents who spent more time sitting on average and adolescents who spent more time sitting in bouts of ≥30 min on average, slept less (p = 0.02 and p = 0.003, respectively).

Conclusions

Based on the between-subjects analyses, interventions focusing on reducing or regularly breaking up sitting time could improve adolescents’ sleep duration on a population level, and vice versa. However, the within-subjects association was only found in one direction and suggests that to sleep sufficiently during the night, adolescents might limit and regularly break up their sitting time the preceding day.

Trial registration

Data have been used from our trial registered at ClinicalTrials.gov (NCT04327414; registered on March 11, 2020).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11694-9.

Study Protocol of a School-Based Randomized Controlled Trial to Promote Cycling to School Among Students in Germany Using Intervention Mapping: The ACTS Project

Background: Despite a high rate of bicycle ownership, the prevalence of cycling to school among children and adolescents in Germany has been constantly low. Cycling to school can contribute to meeting the physical activity recommendations, which the majority of children and adolescents in Germany do not meet.

Methods: By using intervention mapping, this study protocol describes the systematic planning process of a school-based intervention in Germany aimed to increase the number of days on which students cycle to school and to increase their physical activity levels. To make sure that the intervention will match the needs of students, we conducted a concept mapping study investigating what students need to cycle to school, as perceived by students, parents, and teachers. The logic model of change was based on an integration of the self–determination theory and the social–ecological model. We structured our intervention as two phases, a preparatory phase with weekly components for and a practical phase with a daily repeated component of the targeted behavior. In the 8-week preparatory phase, teachers, parents, and peers will be involved. The content of the 12-week practical phase will involve peers only and was considered promising based on the findings from a systematic review that we conducted to identify the effective strategies of school-based interventions to promote cycling to school among children and adolescents. Overall, our intervention includes 27 behavior change techniques. A researcher, student assistants, teachers, and other collaborators will implement the intervention; a whole-of-school approach with components performed before, during, and after school was chosen. As a study design, we decided to draft a two-arm three-level cluster randomized controlled trial. Both the effect and process evaluation were prepared. In the first instance, approximately 250 students of 12–15 years of age from grade 7 or 8, who attend a secondary school of intermediate or high educational level located in (sub)urban regions in Southern Germany, will pilot the intervention.

Discussion: We expect to provide an effective and sustainable intervention for students, which gives insights into the mechanisms of change concerning the behavior of cycling to school and its influence on physical activity levels.

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

Background

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

Method

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

Results

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

Conclusion

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