Individual and day-to-day differences in domain-specific physical activity of 10- to 11-year-old children in Denmark-Measured using GPS and accelerometry.

OBJECTIVE: Physical activity (PA) and the achievement of 60 min of moderate-to-physical-activity daily is declining in school-aged-children, and effective strategies to increase PA is needed. We aimed to examine the individual and day-to-day distribution of PA on schooldays among children aged 10-11 in 4 domains-school, home, transport, and other. METHODS: Data were collected from August to September 2020 using accelerometer and GPS data to measure daily PA-levels and to locate in which domain PA occurs. Daily PA-levels were assessed in each domain, and analyses of the individual and day-to-day differences in PA-levels were calculated. RESULTS: The school domain contributed the most to children's daily MVPA with 47% of average MVPA, followed by the home domain with 26% of daily average MVPA, the other domain with 19% of daily average MVPA and the transport domain with 8% of daily average MVPA. Our results showed individual differences in where PA occurs, day-to-day differences in total MVPA and day-to-day differences in the MVPA-levels across domains. CONCLUSIONS: The school domain contributed the most to children's MVPA-levels followed by the domains of home, other, and transport. Our study indicated that PA-levels and the distribution of PA across domains differ from day-to-day. Future interventions should target more than one domain to accommodate these individual- and day-to-day differences in the goal of increasing PA-levels and to reduce the decline in PA seen from childhood to adolescence.

Identifying multilevel predictors of behavioral outcomes like park use: A comparison of conditional and marginal modeling approaches.

This study compared marginal and conditional modeling approaches for identifying individual, park and neighborhood park use predictors. Data were derived from the ParkIndex study, which occurred in 128 block groups in Brooklyn (New York), Seattle (Washington), Raleigh (North Carolina), and Greenville (South Carolina). Survey respondents (n = 320) indicated parks within one half-mile of their block group used within the past month. Parks (n = 263) were audited using the Community Park Audit Tool. Measures were collected at the individual (park visitation, physical activity, sociodemographic characteristics), park (distance, quality, size), and block group (park count, population density, age structure, racial composition, walkability) levels. Generalized linear mixed models and generalized estimating equations were used. Ten-fold cross validation compared predictive performance of models. Conditional and marginal models identified common park use predictors: participant race, participant education, distance to parks, park quality, and population >65yrs. Additionally, the conditional mode identified park size as a park use predictor. The conditional model exhibited superior predictive value compared to the marginal model, and they exhibited similar generalizability. Future research should consider conditional and marginal approaches for analyzing health behavior data and employ cross-validation techniques to identify instances where marginal models display superior or comparable performance.

Where Are Czech Adolescents Active? The Patterns of Movement and Transport Behavior in Different Active Living Domains.

To understand the environmental determinants of physical activity (PA), precise spatial localization is crucial. This cross-sectional study focuses on the spatiotemporal distribution of PA among Czech adolescents (n = 171) using Global Positioning System loggers and accelerometers. The results showed that adolescents spent most of their time in sedentary behavior, with 57.2% and 58.5% of monitored time at home and school, respectively. The park and playground had the lowest proportion of sedentary behavior but also the lowest amount of moderate to vigorous PA (MVPA). However, when considering the time spent in each domain, the highest proportion of MVPA was seen in publicly accessible playgrounds (13.3% of the time). Chi-square analysis showed that the relative distribution of different PA intensities did not differ across spatial domains. Based on these results, the authors propose 2 key strategies for increasing MVPA in adolescents: Increase the time spent in activity-supportive environments, such as parks and playgrounds, and design techniques to increase MVPA at home and school settings.

Youth-centred participatory action approach towards co-created implementation of socially and physically activating environmental interventions in Africa and Europe: the YoPA project study protocol.

INTRODUCTION: The majority of adolescents do not meet guidelines for healthy behaviours, posing major risks for developing multiple non-communicable diseases. Unhealthy lifestyles seem more prevalent in urban than rural areas, with the neighbourhood environment as a mediating pathway. How to develop and implement sustainable and effective interventions focused on adolescent health and well-being in urban vulnerable life situations is a key challenge. This paper describes the protocol of a Youth-centred Participatory Action (YoPA) project aiming to tailor, implement, and evaluate social and physical environmental interventions. METHODS AND ANALYSIS: In diverse urban environments in Denmark, the Netherlands, Nigeria and South Africa, we will engage a dynamic group of 15-20 adolescents (12-19 years) growing up in vulnerable life situations and other key stakeholders (eg, policy makers, urban planners, community leaders) in local co-creation communities. Together with academic researchers and local stakeholders, adolescents will take a leading role in mapping the local system; tailoring; implementing and evaluating interventions during participatory meetings over the course of 3 years. YoPA applies a participatory mixed methods design guided by a novel Systems, User perspectives, Participatory co-creation process, Effects, Reach, Adoption, Implementation and Maintenance framework assessing: (i) the local systems, (ii) user perspectives, (iii) the participatory co-creation process, (iv) effects, (v) reach, (vi) adoption, (vii) implementation and (viii) maintenance of interventions. Through a realist evaluation, YoPA will explore why and how specific outcomes were reached (or not) in each setting (n=800-1000 adolescents in total). ETHICS AND DISSEMINATION: This study received approval from the ethics committees in Denmark, the Netherlands, Nigeria and South Africa and will be disseminated via various collaborative dissemination activities targeting multiple audiences. We will obtain informed consent from all participants. We envision that our YoPA co-creation approach will serve as a guide for participation of adolescents in vulnerable life situations in implementation of health promotion and urban planning in Europe, Africa and globally. TRIAL REGISTRATION NUMBER: NCT06181162.

Association between preschooler outdoor play and home yard vegetation as measured by high resolution imagery: Findings from the PLAYCE study.

Outdoor play in the home yard is an important source of physical activity for many preschoolers. This study investigated if home yard size and vegetation are related to preschooler outdoor play time. High-resolution remotely sensed data were used to distinguish between types of vegetation coverage in the home yard. Shrub and tree cover, and yard size, were positively associated with outdoor play. Following stratification by socio-economic status (SES - parent education), only tree cover was positively associated with preschooler outdoor play in low SES households. All types of vegetation cover were positively associated with preschooler outdoor play in higher SES households. This study highlights the importance of larger yard sizes and higher levels of vegetation for facilitating outdoor play in preschoolers.

The built environment and child obesity: A review of Australian policies.

Child obesity is a serious public health challenge affected by both individual choice and societal and environmental factors. The main modifiable risk factors for child obesity are unhealthy eating and low levels of physical activity, both influenced by aspects of the built environment. Coordinated government policy across jurisdictions, developed using strong research evidence, can enable built environments that better support healthy lifestyles. This study reviewed current Australian and Western Australian government policies to understand if and how they address the impact of the built environment on child obesity, physical activity, sedentary behavior, and diet. Current government policy documents related to the built environment and child health were analyzed using the Comprehensive Analysis of Policy on Physical Activity framework. Ten Australian and 31 Western Australian government policy documents were identified. Most referred to the role of the built environment in supporting physical activity. Very few policies mentioned the built environment's role in reducing sedentary behaviors, supporting healthy eating, and addressing obesity. Few recognized the needs of children, and none mentioned children in policy development. Future government policy development should include the voices of children and child-specific built environment features. Inter-organizational policies with transparent implementation and evaluation plans are recommended.

Prioritizing a research agenda on built environments and physical activity: a twin panel Delphi consensus process with researchers and knowledge users.

BACKGROUND: The growth of urban dwelling populations globally has led to rapid increases of research and policy initiatives addressing associations between the built environment and physical activity (PA). Given this rapid proliferation, it is important to identify priority areas and research questions for moving the field forward. The objective of this study was to identify and compare research priorities on the built environment and PA among researchers and knowledge users (e.g., policy makers, practitioners). METHODS: Between September 2022 and April 2023, a three-round, modified Delphi survey was conducted among two independent panels of international researchers (n = 38) and knowledge users (n = 23) to identify similarities and differences in perceived research priorities on the built environment and PA and generate twin 'top 10' lists of the most important research needs. RESULTS: From a broad range of self-identified issues, both panels ranked in common the most pressing research priorities including stronger study designs such as natural experiments, research that examines inequalities and inequities, establishing the cost effectiveness of interventions, safety and injuries related to engagement in active transportation (AT), and considerations for climate change and climate adaptation. Additional priorities identified by researchers included: implementation science, research that incorporates Indigenous perspectives, land-use policies, built environments that support active aging, and participatory research. Additional priorities identified by knowledge users included: built environments and PA among people living with disabilities and a need for national data on trip chaining, multi-modal travel, and non-work or school-related AT. CONCLUSIONS: Five common research priorities between the two groups emerged, including (1) to better understand causality, (2) interactions with the natural environment, (3) economic evaluations, (4) social disparities, and (5) preventable AT-related injuries. The findings may help set directions for future research, interdisciplinary and intersectoral collaborations, and funding opportunities.

The role of playgrounds in the development of children's fundamental movement skills: A scoping review.

Fundamental movement skills (FMS) are the basic skills children should develop but are low in children from high-income countries. Literature indicates that playgrounds can play an important role challenging children's balance, agility, and coordination. However, knowledge on the influence of playgrounds on children's FMS development is fragmented. The aim of the present scoping review was to create an overview of all research that is relevant when studying the influence of unstructured playground play on children's FMS. Four electronic databases (Scopus, Web of Science, SportDiscus, and PsycInfo) were searched systematically in May 2022 and October 2023 following the PRISMA guidelines, leading to a final set of 14 publications meeting the inclusion criteria. The results of these publications indicate that it is important to design playgrounds with various features targeting balance, climbing, throwing, and catching to provide opportunities for children to enhance each FMS (i.e., stability, locomotor skills, and object control skills). Also, spreading features over a large area of the playground seems to ensure ample space per child, stimulate children to use locomotor skills by moving to and from features, and to play active games without equipment. Possibly, also natural play settings develop children's FMS. These findings, however, should be read with caution. More experimental studies using objective and standardized FMS tests are needed in this research field for a more robust conclusion.

Recreational walking and perceived environmental qualities: a national map-based survey in Denmark.

BACKGROUND: The aim of the study is to explore the diversity in recreational walking motives across groups with different sociodemographic characteristics, and to use a dynamic and person-centered approach to geographically assess recreational walking behavior, and preferences for place quality related to recreational walking. METHODS: A total of 1838 adult respondents (age 15-90 years), who engage in recreational walking, participated in the map-based survey. We used the online platform Maptionnaire to collect georeferenced information on the respondents' home location, other start locations for walking trips, and point of interest on their trips. Distance between home location and other start locations as well as point of interest were computed using a Geographic Information System (GIS). Additional information on recreational walking behavior and motives were collected using the traditional questionnaire function in Maptionnaire. RESULTS: The most prevalent motives for walking were mental well-being and physical health, together with enjoyment and experiences related to walking. Having a tertiary education was positively associated with mental well-being motive, experiences, and taking the dog and the children outside. Income was also positively associated with experiences and walking the dog together with enjoyment of walking and spending time with others. Using the map-based approach, we found that recreational walking often starts at a location away from home and is not limited to the nearest neighborhood. A total of 4598 points of interest were mapped, and the most frequently reported place qualities were greenery, water, wildlife, good views, and tranquility. CONCLUSION: We used a dynamic and person-centered approach and thereby giving the respondents the opportunity to point to relevant locations for their walking behavior independently of their residential neighborhood. Recreational walking often starts away from home or is not limit to the nearest neighborhod. The median distance from home to the mapped points of interests was between 1.0 and 1.6 km for home-based trips and between 9.4 and 30.6 km for trips with other start locations. The most popular place quality related to the mapped points were greenery, water, wildlife, good views, and tranquility.

Association of composite park quality with park use in four diverse cities.

Park use has numerous health benefits. However, little research has investigated how the combination of park facilities, amenities, and conditions are related to park visitation. This study examined the association between a novel composite park quality metric and the use of specific parks, including variations by demographics. Data were collected in 128 census block groups across four diverse cities in the USA. Adults (n = 262) used an online, map-based survey to indicate which parks within one half-mile they had used within the past 30 days. All parks (n = 263) were audited using the Community Park Audit Tool, and a composite quality metric was calculated by standardizing and averaging six key components: access, facilities, amenities, aesthetic features, quality concerns, and neighborhood concerns. A total of 2429 participant-park pairs were analyzed. The average park quality score was 40.4/100 (s.d. = 30.2). For the full sample, a greater park quality score was significantly related to park use (OR = 1.02, 95% CI = 1.01-1.03) such that for each one unit increase in a park's quality score, there was a 2% increase in the likelihood of the park being used. There was also a significant interaction by gender, with park quality associated with park use among females (OR = 1.03, 95% CI = 1.02-1.05) but not males (OR = 1.00, 95% CI = 0.99-1.02). Enhancing overall park quality may increase the likelihood of a park being used. Future research can explore the utility of this comprehensive quality metric for predicting other health behaviors and outcomes and how interventions to enhance park quality augment park use and health over time.

Device-based physical activity measures for population surveillance-issues of selection bias and reactivity.

Background: Device-based measurement in physical activity surveillance is increasing, but research design choices could increase the risk of self-selection bias and reactive behaviour. The aim of this study is to compare the self-reported physical activity profiles of four different samples: participants in a large national survey, participants in a telephone-based survey of non-responders, participants in the large national survey who accepted the invitation to device-based measuring, and the same sample during the week of monitoring. Methods: In October 2020, 163,133 Danish adults participated in a national survey and of those 39,480 signed up for device-based measurements. A balanced random sample (n = 3,750) was invited to wear an accelerometer of whom 1,525 accepted the invitation. Additionally, a short telephone-based survey on 829 non-responders to the national survey was conducted. Sociodemographic characteristics and self-reported weekly frequencies of physical activity across four domains are compared. Results: The participants in the national survey were older, more often female, and more often not working. Participants in the telephone-based survey were younger, more often doing unskilled work, and were more often active at home and at work. The participants in the device-based sample were more often active during transport and leisure in the national survey, and participants categorized in the most active category increased during the week of monitoring from 29.0% to 60.7% and from 58.5% to 81.7% for active transport and leisure activities, respectively. Conclusion: Recruiting a population representative sample for device-based measurement of physical activity is challenging, and there is a substantial risk of sample selection bias and measurement reactivity. Further research in this area is needed if device-based measures should be considered for population physical activity surveillance.

Neighborhood Places for Preschool Children's Physical Activity: A Mixed-Methods Study Using Global Positioning System, Geographic Information Systems, and Accelerometry Data.

BACKGROUND: This study adds to the current literature by using a novel device-based method to explore where preschool children are physically active outside of home and childcare settings. This study combined accelerometry with geospatial data to explore the influence of the environment on preschool children's physical activity by objectively identifying the locations where preschool children engage in moderate to vigorous physical activity (MVPA) within and outside of their neighborhood. METHODS: Accelerometry, Global Positioning System, and Geographic Information Systems data from 168 preschool children aged 2-5 years were processed in ArcGIS Pro to identify locations (per 25 × 25-m fishnet cell) with high MVPA counts. Locations with high MVPA counts were defined as those with the top 20% of MVPA counts per fishnet cell. The land use for high MVPA count location was determined for 3 domains: <500 m from home, 500 to 1600 m from home, and >1600 m from home. RESULTS: Locations with high MVPA counts <500 m from home were playgrounds (66.6%), schools (16.7%), and parks (16.7%). Locations with high MVPA counts 500 to 1600 m from home included playgrounds (33.3%), nonhome residential (29.6%), childcare centers (11.1%), and parks (3.7%). Locations with high MVPA counts >1600 m from home included nonhome residential (54.7%), sports and recreation centers (11.1%), playgrounds (6.8%), and parks (5.3%). CONCLUSIONS: Our findings highlight that local parks and playgrounds provide physical activity opportunities for preschool children, yet beyond the local neighborhood, the homes of others are important locations for preschool children to accumulate MVPA. These findings can be used to inform the design of current and future neighborhood places to better accommodate preschool children's MVPA.

Adaptations to scale-up an early childhood education and care physical activity intervention for real-world availability - Play Active.

BACKGROUND: Adaptations for scale-up are ubiquitous but are rarely described in detail. Adaptations may be a key reason for the "scale-up penalty" which is when there is a reduction in intervention effect size following scale-up. The Play Active intervention consists of a physical activity policy for early childhood education and care (ECEC) services, with accompanying implementation support strategies. It was first implemented with 81 ECEC services in Perth, Western Australia, in 2021 - with significant positive changes in physical activity practice uptake. The aim of this paper is to describe the extent, type, fidelity consistency, goals, size, scope, and proposed impact of proposed adaptations to the implementation support strategies for scaling-up Play Active. METHODS: Proposed adaptations were defined as planned changes, made prior to making the intervention available. The authors created a list of adaptations from a comparison of the Play Active implementation support strategies, before and after adaptation for proposed statewide availability across Western Australia, Queensland and South Australia, Australia. We used the Framework for Reporting Adaptations and Modifications-Enhanced Implementation Strategies (FRAME-IS) to code adaptations to implementation support strategies. Three authors coded each adaptation and rated their size, scope and proposed impact. RESULTS: Fifty-three adaptations to Play Active were identified. Most (68%) were proposed for the 'content' of implementation strategies, including aspects of their delivery. In practice, this involved changing the delivery mode of implementation support strategies from phone call and email support, to website-based delivery. More than half (56%) of adaptations involved 'adding elements' for scale-up. Most adaptations were 'fidelity consistent' (95%). The main goals for adaptations were related to 'increasing the acceptability, appropriateness, or feasibility' (45%), 'decreasing the costs' (19%) and 'increasing adoption of the evidence-based practice' (19%). Adaptations were small to medium in size, with most proposed to have a positive (87%) or neutral (8%) effect on the effectiveness of the intervention, rather than negative (4%). CONCLUSIONS: A large number of small, fidelity-consistent, adaptations were proposed for Play Active scale-up. Overall, the process of reporting adaptations was found to be feasible. To understand the impact of these adaptations, it will be important to re-evaluate implementation, effectiveness and process outcomes, at-scale.

The moderating role of parent perceptions in relationships between objectively measured neighbourhood environment attributes and pre-schooler's physical activity: Findings from the PLAYCE study.

We examined the moderating effects of parent perceptions of the neighbourhood environment on associations between objectively measured neighbourhood environment attributes and physical activity among pre-schoolers. The number of neighbourhood parks was positively associated with pre-schooler energetic play when parents had above average perceptions of access to services. Objectively measured street connectivity was associated with fewer minutes of energetic play when pedestrian and traffic safety was perceived to be below average by parents. Greater understanding of the role played by parents in pre-schooler's exposure to physically active supportive environments is needed to inform environmental interventions for specific age groups.

Play Active physical activity policy intervention and implementation support in early childhood education and care: results from a pragmatic cluster randomised trial.

BACKGROUND: Policy interventions to increase physical activity in early childhood education and care (ECEC) services are effective in increasing physical activity among young children. However, a large proportion of ECEC services do not have nor implement a physical activity policy. Play Active is an evidence-informed physical activity policy intervention with implementation support strategies to enable ECEC services to successfully implement their policy. This study examined the effectiveness, implementation, and process outcomes of Play Active. METHODS: A pragmatic cluster randomised trial in 81 ECEC services in Perth, Western Australia was conducted in 2021. Services implemented their physical activity policy over a minimum of three months. The effectiveness outcomes were changes in educator practices related to daily time provided for total physical activity and energetic play. Implementation outcomes included changes in director- and educator-reported uptake of policy practices and director-reported uptake of high impact and low effort policy practices. Process evaluation outcomes included awareness, fidelity, reach, and acceptability of the intervention and implementation strategies. Analysis involved descriptive statistics and generalised linear mixed effects models. RESULTS: There was a significant increase in the uptake of director-reported policy practices (p = 0.034), but no change in the uptake of the subset of high impact and low effort policy practices. Intervention group educators reported high awareness of the Play Active policy recommendations (90%). Play Active acceptability was high among educators (83%) and directors (78%). Fidelity and reach were high for most implementation support strategies (> 75%). There were no significant changes in the amount of physical activity or energetic play educators provided to children or in the proportion of educators providing the policy recommended ≥ 180 min of physical activity/day or ≥ 30 min of energetic play/day for intervention compared to wait-listed comparison services. CONCLUSIONS: Play Active resulted in significantly higher uptake of physical activity practices. However, there was no change in the amount of physical activity provided to children, which may be explained by the relatively short policy implementation period. Importantly, Play Active had high awareness, fidelity, reach, and acceptability. Future research should investigate the effectiveness of Play Active over longer implementation periods and its scalability potential. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (reference number 12620001206910, registered 13/11/2020, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378304&isReview=true ).

How to select interventions for promoting physical activity in schools? Combining preferences of stakeholders and scientists.

BACKGROUND: The failure to scale-up and implement physical activity (PA) interventions in real world contexts, which were previously successful under controlled conditions, may be attributed to the different criteria of stakeholders and scientists in the selection process of available interventions. Therefore, the aim of our study was to investigate and compare the criteria applied by local stakeholders and scientists for selecting amongst suitable school-based PA interventions for implementation. METHODS: We conducted a three-round repeated survey Delphi study with local stakeholders (n = 7; Bremen, Germany) and international scientific PA experts (n = 6). Independently for both panels, two rounds were utilized to develop a list of criteria and the definitions of criteria, followed by a prioritization of the criteria in the third round. For each panel, a narrative analysis was used to rank-order unique criteria, list the number of scorers for the unique criteria and synthesize criteria into overarching categories. RESULTS: The stakeholders developed a list of 53 unique criteria, synthesized into 11 categories with top-ranked criteria being 'free of costs', 'longevity' and 'integration into everyday school life'. The scientists listed 35 unique criteria, synthesized into 7 categories with the top-ranked criteria being 'efficacy', 'potential for reach' and 'feasibility'. The top ranked unique criteria in the stakeholder panel were distributed over many categories, whereas four out of the top six criteria in the scientist panel were related to 'evidence'. CONCLUSIONS: Although stakeholders and scientists identified similar criteria, major differences were disclosed in the prioritization of the criteria. We recommend an early collaboration of stakeholders and scientists in the design, implementation, and evaluation of PA interventions.

Effect of nationwide school policy on device-measured physical activity in Danish children and adolescents: a natural experiment.

Background: A new Danish school policy with a requirement for 45 min physical activity daily during school hours was introduced in 2014. The objective of this natural experiment was to evaluate the effect of this nationwide school policy on physical activity in Danish children and adolescents. Methods: Four historical studies completed between 2009 and 2012 comprised the pre-policy study population. Post-policy data were collected in 2017/18. All post-policy schools were represented in the four pre-policy studies. Age-groups and seasons were matched. In total, 4816 children and adolescents aged 6-17 were included in the analyses (2346 pre-policy and 2470 post-policy). Children and adolescents were eligible if they had accelerometer measurements and did not have any physical disabilities preventing activity. Physical activity was measured by accelerometry. Main outcome was any bodily movement. Secondary outcomes were moderate to vigorous physical activity and overall movement volume (mean counts per minute). Findings: The school policy interrupted a linear decreasing pre-policy trend in physical activity during school hours. All activity outcomes increased post-policy during a standardized school day (8:10 am-1 pm). Increases were more pronounced in the youngest children. Specifically, we observed a daily increase during a standardized school day in 2017/2018 of 14.2 min of movement (95% CI: 11.4-17.0, p < 0.001), 6.5 min of moderate to vigorous physical activity (95% CI: 4.7-8.3, P < 0.001), and 141.8 counts per minute (95% CI: 108.5-175.2, P < 0.001). Interpretation: A national school policy may be an important strategy to increase physical activity during school hours among children and adolescents. Funding: The Danish Foundation TrygFonden has funded the PHASAR project (ID 115606).

Built Environments And Child Health in WalEs and AuStralia (BEACHES): a study protocol.

INTRODUCTION: Childhood obesity and physical inactivity are two of the most significant modifiable risk factors for the prevention of non-communicable diseases (NCDs). Yet, a third of children in Wales and Australia are overweight or obese, and only 20% of UK and Australian children are sufficiently active. The purpose of the Built Environments And Child Health in WalEs and AuStralia (BEACHES) study is to identify and understand how complex and interacting factors in the built environment influence modifiable risk factors for NCDs across childhood. METHODS AND ANALYSIS: This is an observational study using data from five established cohorts from Wales and Australia: (1) Wales Electronic Cohort for Children; (2) Millennium Cohort Study; (3) PLAY Spaces and Environments for Children's Physical Activity study; (4) The ORIGINS Project; and (5) Growing Up in Australia: the Longitudinal Study of Australian Children. The study will incorporate a comprehensive suite of longitudinal quantitative data (surveys, anthropometry, accelerometry, and Geographic Information Systems data) to understand how the built environment influences children's modifiable risk factors for NCDs (body mass index, physical activity, sedentary behaviour and diet). ETHICS AND DISSEMINATION: This study has received the following approvals: University of Western Australia Human Research Ethics Committee (2020/ET000353), Ramsay Human Research Ethics Committee (under review) and Swansea University Information Governance Review Panel (Project ID: 1001). Findings will be reported to the following: (1) funding bodies, research institutes and hospitals supporting the BEACHES project; (2) parents and children; (3) school management teams; (4) existing and new industry partner networks; (5) federal, state and local governments to inform policy; as well as (6) presented at local, national and international conferences; and (7) disseminated by peer-reviewed publications.

The geospatial and conceptual configuration of the natural environment impacts the association with health outcomes and behavior in children and adolescents.

BACKGROUND: Studies investigating associations between natural environments and health outcomes or health behaviors in children and adolescents yielded heterogenous results to date. This may be the result of different geospatial configurations of the natural environment and confounding characteristics of the study population. Thus, we investigated how the relationship between the natural environment and mental health, muscular fitness, and physical activity varies depending on the geospatial configuration of nature and children's and adolescents' characteristics. METHODS: Data were derived from the German Motorik-Modul (MoMo) cohort study (2018-2020) that investigates physical activity, muscular fitness, and health parameters in a national sample of children and adolescents (N = 2843) between four and 17 years (Mage = 10.46 ± 3.49 years; 48.3% girls). Mental health was assessed via questionnaire, muscular fitness via standing long jump, and physical activity with 7-day accelerometer measurement. Using geographic information systems, land cover, and land use data, three different nature definitions were applied. Both circular buffers (100-1000 m) and street-network buffers (1000-5000 m) were created for each of the nature definitions. Associations were explored with linear regression models, and interaction analysis was used to investigate how those relationships vary by gender, age, and socio-economic status. RESULTS: The relationship between the three outcomes and the natural environment varied considerably depending on the nature definition, buffer size, and buffer type, as well as socio-demographic characteristics. Specifically, when comparing youth with a high socio-economic status to those with a medium socio-economic status, smaller circular buffer distances were related to less physical activity, but larger street-network buffer distances were related to greater mental health problems. Distinct relationships also occurred for youth with low socio-economic status in those relationships, with the pattern being less clear. CONCLUSIONS: For future health research studies that investigate the role of the natural environment, we argue for the development of an a-priori model that integrates both geospatial considerations (nature definition, buffer type, and buffer size) and conceptual considerations (health outcome/behavior, sample characteristics) based on potentially underlying mechanisms that link the natural environment and the health outcome or behavior under investigation to theoretically underpin the geospatial configuration of the natural environment.