Relationship between eating behaviors and physical activity of preschoolers and their peers: a systematic review

Associations Between Combinations of 24-Hour Movement Behaviors and Dietary Outcomes in Children and Adolescents: A Systematic Review

Background/Objectives: Twenty-four-hour movement behaviors, including physical activity, sedentary time, and sleep, are associated with a range of health outcomes. However, the relationship between the combinations of these behaviors and dietary outcomes in young populations remains unclear. We conducted a systematic review to explore how combined movement behaviors are linked to dietary outcomes in children and adolescents. Methods: We searched MEDLINE, Embase, and PsycINFO from January 2017 to July 2024, including studies that were (1) written in English, (2) published in peer-reviewed journals, (3) quantitatively analyzed two or three movement behaviors with dietary outcomes, and (4) focused on populations aged between 0 and 18 years. Results: Ten cross-sectional studies met these criteria. The majority of studies (6 out of 10) assessed all three movement behaviors, although sleep was less frequently examined, appearing in only 4 of the studies. Our findings indicated that adhering to all movement recommendations was consistently associated with healthier dietary patterns, including a higher consumption of fruits, vegetables, nuts, fish, and cereals, and a lower intake of sweets and pastries. Additionally, adhering to physical activity and sedentary time guidelines was linked to improved dietary habits in children, including more fruit and vegetable intake and less sugary drink and snack consumption. Conversely, higher sedentary time and inadequate sleep were linked to poorer dietary outcomes, particularly lower fruit intake and hydration. Conclusions: This review suggests that meeting movement behavior guidelines correlates with healthier dietary outcomes in children and adolescents. However, given the limited number of studies and their cross-sectional design, further high-quality research, including longitudinal and intervention studies, is needed to clarify causal relationships.

Where and how to invest in greenspace for optimal health benefits: a systematic review of greenspace morphology and human health relationships

Research on the relationship between greenspace morphology and health is a growing field that informs the spatial design of greenspace to enhance health outcomes. This study reviews the current progress, methodologies, and knowledge gaps in this area. From a database search of 272 940 English articles and 39 053 Chinese articles up to April 18, 2024, we identified 22 and 7 studies on the topic for further evaluation. Predominantly cross-sectional and neighbourhood-scale analyses were conducted using land cover maps ranging from 0·25 to 100 meters in resolution. Six primary characteristics of greenspace morphology have been studied, including size, shape, fragmentation, connectedness, aggregation, and diversity. While associations between greenspace morphology and health outcomes have been observed, both their reliability and generalisability remain suggestive due to ecological study designs and heterogeneity among studies. Future research should prioritise individual-level prospective cohorts and intervention studies. Exploring mechanisms linking greenspace morphology and health, determining optimal map resolution, and distinguishing it from greenness magnitude in statistical analysis is essential. This evidence is crucial for health-promoting greenspace planning and should be routinely integrated into urban epidemiological research.

Parental support for physical activity and children's physical activities: a cross-sectional study

BACKGROUND

Physical activity (PA) in school-aged children is imperative for physical and mental development. However, there has been reduced PA among children in recent years owing to environmental changes, resulting in declining physical strength and athletic ability. Although parents' and children's PA has been found to be correlated, the specific parental caregiving attitudes associated with children's actual levels of PA during school-age years remain unknown. Therefore, this study aimed to examine the relationship between parental support for PA and children's levels of PA.

METHODS

In 2017, a self-reported questionnaire survey was administered to 1,515 third-grade students (8-9 years old) and their caregivers in Nagoya, Aichi, a major metropolitan area in Japan. The main items surveyed included the attitudes of children and parents towards PA and the children's actual PA level. Multiple regression analysis was conducted with parental involvement related to PA as the explanatory variable and children's PA as the objective variable.

RESULTS

In total, 717 children with valid responses were included in the analysis. The mean age of the children was 9.08 ± 0.33 years; 366 (51.0%) were boys, and 351 (49.0%) were girls. For moderate-to-vigorous and vigorous PA, PA levels tended to be significantly higher in children whose parents provided logistic support such as enrolling their children in a sports club. However, for moderate PA and walking, PA levels tended to be significantly higher in children whose parents used community resources. Modeling and limiting sedentary activities were not associated with children's PA.

CONCLUSIONS

The results of this study suggest that direct parental assistance for PA such as logistic support encourages children to engage in moderate-to-vigorous PA; in addition, parental use of community resources may encourage children to engage in moderate and light PA such as walking. Conversely, indirect and negative involvement such as modeling and limiting sedentary activities were not associated with children's PA. Therefore, logistic support may need to be strengthened to encourage moderate-to-vigorous and vigorous PA, which is important for children's health.

Scoping review of children's and youth's outdoor play publications in Canada

INTRODUCTION

Since 2015, interest in the benefits of outdoor play for physical, emotional, social and environmental health, well-being and development has been growing in Canada and elsewhere.

METHODS

This scoping review aims to answer the question, "How, and in what context, is children's and youth's outdoor play being studied in Canada?" Included were studies of any type on outdoor play published after September 2015 in English or French by authors from Canadian institutions or assessing Canadian children and/or youth. Articles retrieved from MEDLINE, CINAHL and Scopus by March 2021 were organized according to eight priority areas: health, well-being and development; outdoor play environments; safety and outdoor play; cross-sectoral connections; equity, diversity and inclusion; professional development; Indigenous Peoples and land-based outdoor play; and COVID-19. Within each priority, study design and measurement method were tallied.

RESULTS

Of the 275 articles included, the most common priority area was health, wellbeing and development (n = 239). The least common priority areas were COVID-19 (n = 9) and Indigenous Peoples and land-based outdoor play (n = 14). Cross-sectional studies were the most common; the least common were rapid reviews. Sample sizes varied from one parent's reflections to 999 951 data points from health databases. More studies used subjective than objective measurement methods. Across priorities, physical health was the most examined outcome, and mental/emotional development the least.

CONCLUSION

A wealth of knowledge on outdoor play in Canada has been produced since 2015. Further research is needed on the relationship between outdoor play and mental/emotional development among children and youth.

Physical Activity Opportunities in US Early Child Care Programs

BACKGROUND AND OBJECTIVES

Physical activity provides health and developmental benefits to young children. The Study of Nutrition and Activity in Child Care Settings describes physical activity opportunities and sedentary occasions for children aged 1 to 5 years at programs participating in the US Department of Agriculture Child and Adult Care Food Program.

METHODS

The Study of Nutrition and Activity in Child Care Settings obtained a nationally representative sample of classrooms within Child and Adult Care Food Program-participating Head Start and child care centers via multistage cluster sampling. For 1 observation day, an observer in each classroom tallied designated outdoor and indoor playspaces; minutes children spent in playspaces; barriers and facilitators to physical activity; and classroom time when most children were physically active (eg, walking, dancing), sedentary (seated, lying down), or neither. Weighted descriptive tabulations by program type compared outdoor physical activity opportunity counts and total physical activity opportunity durations to national guidelines. Multivariate regression analysis investigated association of barriers with physical activity opportunity duration.

RESULTS

The sample included 227 classrooms, 96 in child care centers and 131 in Head Start programs. All had sedentary occasions outside meals, snacks, and naps; virtually all offered opportunities for physical activity. Seventy-four percent of programs met national guidance on sufficient number of outdoor opportunities, weather permitting. Just 50% met guidance of ≥60 to 90 minutes of physical activity, whereas only 43% met both sets of guidance. Weather and staff not joining in outdoor play were associated with 74 and 31 fewer minutes devoted to physical activity, respectively.

CONCLUSIONS

Findings suggest ample room for improvement in provision of physical activity opportunities during child care.

A Mobile App to Increase Fruit and Vegetable Acceptance Among Finnish and Polish Preschoolers: Randomized Trial

Background

Early childhood education and care (ECEC) centers are ideal venues for food education. As smartphones and tablets are becoming increasingly popular in ECEC centers, technology can be used to deliver such pedagogical content. Evidence suggests that video games can affect fruit and vegetable (FV) consumption among 9- to 12-year-old children, but studies among preschoolers are scarce.

Objective

This paper describes the development of the Mole’s Veggie Adventures app and its effectiveness in increasing FV acceptance among Finnish and Polish preschoolers aged 3 to 6 years.

Methods

A multiprofessional team created an app to be used in ECEC centers in groups of 3 to 10 children. The app aimed to increase vegetable acceptance, and it was built using elements that support the development of self-regulation and social skills. Altogether, 7 Finnish and 4 Polish ECEC centers participated in the study. Before randomization, parents reported background factors and their children’s willingness to taste different FVs. The ECEC professionals in the intervention arm were instructed to use the app at least once a week during the 3- to 4-week intervention period. The main outcomes in this unblinded, cluster-randomized study were FV acceptance and relative FV acceptance. The first was calculated as a sum variable describing the children’s willingness to taste 25 different FVs, the second as FV acceptance divided by the number of FVs served. We used analysis of covariance to compare the FV acceptance and relative FV acceptance scores between the intervention and control groups at follow-up.

Results

A total of 221 children were included in the analysis. At follow-up, the intervention group (115/221, 52%) had higher FV acceptance scores (baseline adjusted difference of mean 7.22; 95% CI 1.41-13.03) than the control group (106/221, 48%). The intervention effect was parallel for relative FV acceptance scores (baseline adjusted difference of mean 0.28; 95% CI 0.05-0.52).

Conclusions

The Mole’s Veggie Adventures app has the potential to increase FV acceptance among preschoolers and can be a valuable tool in supporting food education in ECEC centers. Furthermore, the app can be feasibly incorporated into preschool routines in countries with different educational environments.

Trial Registration

ClinicalTrials.gov NCT05173311; https://tinyurl.com/4vfbh283

Application of the multiphase optimisation strategy to develop, optimise and evaluate the effectiveness of a multicomponent initiative package to increase 2-to-5-year-old children's vegetable intake in long day care centres: a study protocol

INTRODUCTION

Globally, children do not eat enough core foods, with vegetable intakes persistently low. Early life is critical for establishing vegetable acceptance and intake. Increased usage of formal childcare has led to the importance of childcare settings shaping children's food intake. This study will use the multiphase optimisation strategy to develop, optimise and evaluate the effectiveness of a multicomponent initiative package to increase 2-to-5-year-old children's vegetable intake in long day care centres.

METHODS AND ANALYSIS

The preparation phase will use existing literature and best practice guidelines to develop three initiatives aiming to: (1) increase vegetable provision at mealtimes, (2) deliver a vegetable-focused sensory curriculum and (3) use supportive mealtime practices encouraging children's tasting of vegetables. The optimisation phase (N=32 centres) will use a 12-week, eight-condition factorial experiment to test main and synergistic effects of the initiatives. The optimum combination of initiatives producing the largest increase in vegetable intake will be identified. The evaluation phase (N=20 centres) will test the effectiveness of the optimised package using a 12-week waitlist randomised controlled trial. Primary outcomes are children's vegetable intake and food group intake at long day care. Secondary outcomes are menu guideline compliance, cook and educator knowledge and skills, and reach. Process evaluation will include fidelity, acceptability, barriers and facilitators, and compatibility with practice. Repeated measures ANOVA with interaction effects (optimisation phase) and linear mixed modelling (evaluation phase) will test effects of the initiatives on vegetable intake.

ETHICS AND DISSEMINATION

This study has received ethics approval from the Flinders University Research Ethics Committee (Project No: 1873) for the optimisation phase. Approval for the evaluation phase will be obtained following completion of optimisation phase. Findings will be disseminated to stakeholders, including long day care centres and childcare organisations; and to researchers via peer-reviewed journals and conferences.

TRIAL REGISTRATION NUMBERS

ACTRN12620001301954, ACTRN12620001323910p.

Social and family factors as determinants of exercise habits in Japanese elementary school children: a cross-sectional study from the Super Shokuiku School Project

BACKGROUND

Many studies have already reported on the relationship between exercise habits and health among schoolchildren. However, few have examined social and/or family factors as determinants of exercise habits.

METHODS

This study's participants included 1721 schoolchildren aged between 6 and 13 who were involved in the Super Shokuiku School Project in January 2016. A survey was conducted to assess gender, grade level, physical activity, lifestyle, overall health, enrichment of school life, social background, and parental lifestyles. Both dislike and lack of physical activity were used to measure poor exercise habits; correlates were analyzed using logistic regression.

RESULTS

"Lack of close friends" had the strongest links with both dislike (adjusted odds ratio [OR] 5.30; 95% confidence interval [CI], 2.78-10.1) and lack of (adjusted OR 5.40; 95% CI, 2.81-10.4) physical activity. Further, children who engaged in long periods of screen time and lacked parental communication also tended to dislike and lack physical activity. Children with mothers who were unemployed (housewives) and had unhealthy lifestyles, as well as those with poor health, were also more likely to lack physical activity.

CONCLUSION

Social and family factors (e.g., having close friends) may be determinants of exercise habits among schoolchildren, independent of their own lifestyle factors. Although a longitudinal study is needed to determine causality, substantial attention may thus be required to these factors when promoting physical activity in children.

Preschool group practices and preschool children's sedentary time: a cross-sectional study in Finland

OBJECTIVES

Preschool is an important setting for regulating sedentary time (ST). The preschool day in Finland follows daily structures by having morning and afternoon slots for group-based activities that can encourage children for movement (eg, free play and outdoor time) or be still (eg, teacher-led sessions and sitting-based circles). This study aims to explore if the weekly routines in preschool and if more frequent visits in places encouraging physical activity (PA) are associated with children's ST during preschool hours.

DESIGN

Cross-sectional DAGIS (Increased Health and Wellbeing in Preschools) study in the years 2015 and 2016.

SETTING

In Finland.

PARTICIPANTS

864 children (48% girls, 4.7 years) from 159 preschool groups in 66 preschools OUTCOME MEASURES: A total of 778 children wore required lengths of time (at least 240 min per preschool day, at least 2 days) the accelerometer during preschool hours. Each preschool group reported their weekly schedule during the week, and one early educator completed a questionnaire covering practices. The following five measures related to weekly structures were formed; times of outdoors (times per day), teacher-led sessions (times per day), free play (low, middle or high), organised PA lessons (no lessons at all/others) and mixed activities (no lessons at all/others), and the following five measures about the frequencies of visits in places encouraging PA; nature trips (times per week), play parks (times per week), neighbourhood sport facilities (no visits at all/others), visits to gym or other indoor facility (no visits at all/others) and field trips to neighbourhoods (times per week). Multilevel linear regression analyses were conducted to measure the associations.

RESULTS

Of all the tested associations, only more frequently conducted nature trips were associated with lower children's ST during preschool hours (β=-1.026; 95% CI -1.804 to -0.248).

CONCLUSION

Frequent nature trips in preschools may be important due to its association with lower preschool children's ST.

Social Support and Modelling in Relation to Physical Activity Participation and Outdoor Play in Preschool Children

Physical activity during early childhood is a prerequisite for healthy development in many cases. The aim of this study was to assess the relationships of social modelling and support from parents, peers, and siblings and domain-specific physical activity participation in a nationwide sample of preschool boys and girls from Germany. 519 preschool children aged 4-6 and one of their parents participated in the 'MoMo' Wave 1 Study between 2009 and 2012. Participants and their parents provided self-reported data on social support modelling, and domain-specific physical activity participation (physical activity in sports clubs, physical activity outside of sports clubs, and outdoor play). Parental, peer, and sibling support and modelling were related to domain-specific physical activity: Parental support was particularly relevant for physical activity in sports clubs, and peer support for outdoor play. Parental modelling was only related to physical activity outside of sports clubs: Maternal modelling was a positive correlate in girls and paternal modelling in boys, respectively. Sibling and peer modelling were especially relevant for physical activity in sports clubs. The results were heterogeneous regarding types and providers of support and modelling. Thus, different providers and types of support should be targeted in physical activity promotion programs for preschool children.

Effectiveness of Teacher-Led Nutritional Lessons in Altering Dietary Habits and Nutritional Status in Preschool Children: Adoption of a NASA Mission X-Based Program

The preschool years are a sensitive period for the development of food preferences that will affect physical growth and life-long health. The promotion of healthy eating and nutritional status was achieved by adapting the US National Aeronautics and Space Administration (NASA) Mission X (MX) Program among young children in South Korea. The intervention program was delivered by nutritional experts and class teachers over 10 weeks. Children from 37 school classes (n = 534) from 7 daycares and kindergartens were randomized into a control group (CG, n = 280) and an intervention group (IG, n = 254). Parents were surveyed for their children’s characteristics and nutrition quotient (NQ) at baseline and at the 10-week follow-up. At baseline, 18.8% (boys: 18.9%; girls: 18.8%) of the subjects were overweight or obese (body mass index ≥ 85th percentile). After the intervention, the mean differences in various anthropometric measures did not differ significantly between the groups in a linear regression model adjusted for age, sex, and type of school. The NQ grades were significantly higher in the IG than the CG after the intervention (p = 0.000). In summary, the 10-week South Korean MX program improved the eating behaviors and nutrition status of young children. A further multisector prevention program is needed to prevent childhood obesity in young children.

Child-care self-assessment to improve physical activity, oral health and nutrition for 2- to 4-year-olds: a feasibility cluster RCT

Background

The Nutrition And Physical Activity Self Assessment for Child Care (NAP SACC) intervention has shown evidence of effectiveness in the USA but not been adapted or assessed for effectiveness in the UK.

Objectives

To evaluate the feasibility and acceptability of implementing NAP SACC in the UK.

Design

Adaptation and development of NAP SACC and feasibility cluster randomised controlled trial (RCT) including process and economic evaluations. Substudies assessed mediator questionnaire test–retest reliability and feasibility of food photography methods.

Setting

Nurseries, staff and parents in North Somerset, Cardiff, Gloucestershire and Bristol.

Participants

Development – 15 early years/public health staff and health visitors, 12 nursery managers and 31 parents. RCT – 12 nurseries and 31 staff, four partners and 168 children/parents. Mediator substudy – 82 parents and 69 nursery staff. Food photography substudy – four nurseries, 18 staff and 51 children.

Intervention

NAP SACC UK partners supported nurseries to review policies and practices and set goals to improve nutrition, oral health and physical activity (PA) over 5 months. Two workshops were delivered to nursery staff by local experts. A home component [website, short message service (SMS) and e-mails] supported parents. The control arm continued with usual practice.

Main outcome measures

Feasibility and acceptability of the intervention and methods according to prespecified criteria.

Data sources

Qualitative data to adapt the intervention. Measurements with children, parents and staff at baseline and post intervention (8–10 months after baseline). Interviews with nursery managers, staff, parents and NAP SACC UK partners; observations of training, workshops and meetings. Nursery environment observation, nursery Review and Reflect score, and resource log. Child height and weight, accelerometer-determined PA and sedentary time, screen time and dietary outcomes using the Child and Diet Evaluation Tool. Staff and parent questionnaires of knowledge, motivation and self-efficacy. Child quality of life and nursery, family and health-care costs. Food photography of everything consumed by individual children and staff questionnaire to assess acceptability.

Results

Thirty-two per cent (12/38) of nurseries and 35.3% (168/476) of children were recruited; no nurseries withdrew. The intervention was delivered in five out of six nurseries, with high levels of fidelity and acceptability. Partners found it feasible but had concerns about workload. The child loss to follow-up rate was 14.2%. There was suggestion of promise in intervention compared with control nurseries post intervention for snacks, screen time, proportion overweight or obese and accelerometer-measured total PA and moderate to vigorous PA. Many parental and nursery knowledge and motivation mediators improved. The average cost of delivering the intervention was £1184 per nursery excluding partner training, and the average cost per child was £27. Fourteen per cent of parents used the home component and the mediator questionnaire had good internal consistency and test–retest reliability. Photography of food was acceptable and feasible.

Limitations

Following nursery leavers was difficult. Accelerometer data, diet data and environmental assessment would have been more reliable with 2 days of data.

Conclusions

The NAP SACC UK intervention and methods were found to be feasible and acceptable to participants, except for the home component. There was sufficient suggestion of promise to justify a definitive trial.

Future work

A multicentre cluster randomised controlled trial to evaluate the effectiveness and cost-effectiveness of NAP SACC UK has been funded by NIHR and will start in July 2019 (PHR NIHR 127551).

Trial registration

Current Controlled Trials ISRCTN16287377.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 7, No. 13. See the NIHR Journals Library website for further project information. Funding was also provided by the North Somerset and Gloucestershire Councils, Development and Evaluation of Complex Interventions for Public Health Improvement (DECIPHer) (MR/KO232331/1), and the Elizabeth Blackwell Institute.

Characteristics of Effective Interventions Promoting Healthy Eating for Pre-Schoolers in Childcare Settings: An Umbrella Review

Early Childhood Education and Care (ECEC) settings have a pivotal role in shaping children's dietary food habits by providing the contextual environment within which they develop these behaviours. This study examines systematic reviews for (1) the effectiveness of interventions to promote healthy eating in children aged 2-5 years attending centre-based childcare; (2) intervention characteristics which are associated with promoting healthy eating and; (3) recommendations for child-health policies and practices. An Umbrella review of systematic reviews was undertaken using a standardized search strategy in ten databases. Twelve systematic reviews were examined using validated critical appraisal and data extraction tools. Children's dietary food intake and food choices were significantly influenced. Interventions to prevent obesity did not significantly change children's anthropometric measures or had mixed results. Evidence was more convincing if interventions were multi-component, addressed physical activity and diet, targeted individual-level and environmental-level determinants and engaged parents. Positive outcomes were mostly facilitated by researchers/external experts and these results were not replicated when implemented in centres by ECEC providers without this support. The translation of expert-led interventions into practice warrants further exploration of implementation drivers and barriers. Based on the evidence reviewed, recommendations are made to inform child-health directed practices and policies.

Socio-cultural determinants of physical activity across the life course: a 'Determinants of Diet and Physical Activity' (DEDIPAC) umbrella systematic literature review

OBJECTIVE

Regular physical activity (PA) reduces the risk of disease and premature death. Knowing factors associated with PA might help reducing the disease and economic burden caused by low activity. Studies suggest that socio-cultural factors may affect PA, but systematic overviews of findings across the life course are scarce. This umbrella systematic literature review (SLR) summarizes and evaluates available evidence on socio-cultural determinants of PA in children, adolescents, and adults.

METHODS

This manuscript was drafted following the recommendations of the 'Preferred Reporting Items for Systematic reviews and Meta-Analyses' (PRISMA) checklist. The MEDLINE, Web of Science, Scopus, and SPORTDiscus databases were searched for SLRs and meta-analyses (MAs) on observational studies published in English that assessed PA determinants between January 2004 and April 2016. The methodological quality was assessed and relevant information on socio-cultural determinants and any associations with PA was extracted. The available evidence was evaluated based on the importance of potential determinants and the strength of the evidence.

RESULTS

Twenty SLRs and three MAs encompassing 657 eligible primary studies investigated potential socio-cultural PA determinants, with predominantly moderate methodological quality. Twenty-nine potential PA determinants were identified that were primarily assessed in children and adolescents and investigated the micro-environmental home/household level. We found probable evidence that receiving encouragement from significant others and having a companion for PA were associated with higher PA in children and adolescents, and that parental marital status (living with partner) and experiencing parental modeling were not associated with PA in children. Evidence for the other potential determinants was limited, suggestive, or non-conclusive. In adults, quantitative and conclusive data were scarce.

CONCLUSIONS

A substantial number of SLRs and MAs investigating potential socio-cultural determinants of PA were identified. Our data suggest that receiving social support from significant others may increase PA levels in children and adolescents, whereas parental marital status is not a determinant in children. Evidence for other potential determinants was limited. This was mainly due to inconsistencies in results on potential socio-cultural determinants of PA across reviews and studies.

TRIAL REGISTRATIONS

This umbrella SLR was recorded on PROSPERO (Record ID: CRD42015010616 ).

Determinants of eating patterns and nutrient intake among adolescent athletes: a systematic review

Background

This review aims to update the influences of sport modalities, sport performance, and non-exercise-related determinant, on eating patterns and nutrient intake outcomes among adolescent competitive athletes.

Methods

The PubMed and Scopus databases were searched for the last 20 years. Observational and intervention studies of all languages on eating patterns and nutrient intake in adolescent (10- to 19-year-old) competitive athletes were included. Study quality and risk of bias were assessed using a Downs and Black instrument. Moreover, the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) evidence system was used to assess the strength of the body of evidence.

Results

Regarding outcomes of 21 included articles, 95.2% of studies focused on nutrient analysis, whereas few of the included articles reported eating patterns. As determinants, most studies analyzed the influences of sport-related (n = 10) and demographic factors (n = 8), among which only sport modalities were significantly associated with nutrient intake. Age and sex were not significantly associated with nutrient intake. All studies were observational, and most were cross-sectional (n = 17) and conducted in developed countries such as the United States and European nations. Most studies evaluated boys, and the sport that received the most attention was soccer.

Conclusions

Athletes do not adjust their nutrient intake or food choice to the demands of the training load or different training sessions, while sport modalities significantly influenced nutrient intake. Moreover, results concerning demographic determinants were inconsistent and thus remain inconclusive.

Trial registration

Prospero CRD42016043310.

Electronic supplementary material

The online version of this article (doi:10.1186/s12937-017-0267-0) contains supplementary material, which is available to authorized users.

Association between childcare educators' practices and preschoolers' physical activity and dietary intake: a cross-sectional analysis

INTRODUCTION

Childcare educators may be role models for healthy eating and physical activity (PA) behaviours among young children. This study aimed to identify which childcare educators' practices are associated with preschoolers' dietary intake and PA levels.

METHODS

This cross-sectional analysis included 723 preschoolers from 50 randomly selected childcare centres in two Canadian provinces. All data were collected in the fall of 2013 and 2014 and analysed in the fall of 2015. PA was assessed using Actical accelerometers during childcare hours for 5 consecutive days. Children's dietary intake was measured at lunch on 2 consecutive days using weighed plate waste and digital photography. Childcare educators' nutrition practices (modelling, nutrition education, satiety recognition, verbal encouragement and not using food as rewards) and PA practices (informal and formal PA promotion) were assessed by direct observation over the course of 2 days, using the Nutrition and Physical Activity Self-Assessment for Child Care tool. Associations between educators' practices and preschoolers' PA and dietary intake were examined using multilevel linear regressions.

RESULTS

Overall, modelling of healthy eating was positively associated with children's intake of sugar (β=0.141, 95% CI 0.03 to 0.27), while calorie (β=-0.456, 95% CI -1.46 to -0.02) and fibre intake (β=-0.066, 95% CI -0.12 to -0.01) were negatively associated with providing nutrition education. Not using food as rewards was also negatively associated with fat intake (β=-0.144, 95% CI -0.52 to -0.002). None of the educators' PA practices were associated with children's participation in PA.

CONCLUSIONS

Modelling healthy eating, providing nutrition education and not using food as rewards are associated with children's dietary intake at lunch in childcare centres, highlighting the role that educators play in shaping preschoolers' eating behaviours. Although PA practices were not associated with children's PA levels, there is a need to reduce sedentary time in childcare centres.

Psychosocial and Environmental Correlates of Sedentary Behaviors in Spanish Children

Purpose. To evaluate children's psychosocial and environmental factors associated with sedentary behavior (SB). Method. The study involved a total of 420 children (mean 9.2 years; 52.9% girls) from the community of Madrid, Spain. SB and physical activity (PA) were objectively measured using accelerometers. TV viewing and potential correlates were assessed by questionnaire. Mixed-model regression analysis, adjusted for clustering within school locations, evaluated the relation of each independent variable with SBs. Results. Girls showed higher levels of SB than boys, whereas boys reported more TV viewing (p < .001 in all cases). Regression analysis showed that MVPA levels were negatively related to objective SB measurement in both boys and girls (p < .001). Parent and friend support to PA were negatively associated with SB on weekdays in boys and girls, respectively (p < .05). In the boys' group, parental professional level was a positive predictor of SB on weekend days (p = .011). Boys with more positive neighborhood perceptions spent less time watching TV (p < .001), whereas mother's leisure-time PA level was a negative correlate of TV viewing in girls' group (p < .01). Conclusion. Different psychosocial and environmental correlates of SB were identified. Present findings are promising targets for interventions to improve children's health.

"Monkey see, monkey do": Peers' behaviors predict preschoolers' physical activity and dietary intake in childcare centers

Preschoolers observe and imitate the behaviors of those who are similar to them. Therefore, peers may be role models for preschoolers' dietary intake and physical activity in childcare centers. This study examined whether peers' behaviors predict change in preschoolers' dietary intake and physical activity in childcare centers over 9months. A total of 238 preschoolers (3 to 5years old) from 23 childcare centers in two Canadian provinces provided data at the beginning (October 2013 and 2014) and the end (June 2014 and 2015) of a 9-month period for this longitudinal study. Dietary intake was collected at lunch using weighed plate waste and digital photography on two consecutive weekdays. Physical activity was assessed using accelerometers over five days. Multilevel linear regressions were used to estimate the influence of peers' behaviors on preschoolers' change in dietary intake and physical activity over 9months. Results showed that preschoolers whose dietary intake or physical activity level deviated the most from those of their peers at the beginning of the year demonstrated greater change in their intakes and activity levels over 9months, which enabled them to become more similar to their peers (all β 95% CI ranged from -0.835 to -0.074). This study suggests that preschoolers' dietary intake and physical activity may be influenced by the behaviors of their peers in childcare centers. Since peers could play an important role in promoting healthy eating behaviors and physical activity in childcare centers, future studies should test interventions based on positive role modeling by children.