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Background Many children aged 0–5 years do not meet the WHO physical activity guidelines. To develop effective, evidence-based interventions, it is necessary to understand which factors are associated with physical activity in early childhood. Objective To summarize the current evidence on correlates of physical activity in 0- to 5-year-old children. Methods First, a systematic umbrella review was conducted following PRISMA guidelines. PubMed, Embase, PsycINFO, and SPORTDiscus were searched up to May 2020 for systematic reviews examining the association between potential correlates and quantitatively measured physical activity in children aged 0–5.9 years. Included reviews were assessed on methodological quality, and results were categorized according to the socio-ecological model. Second, 31 international researchers of physical activity in young children participated in an expert panel to reflect on the outcomes of the umbrella review and propose directions for future research. Results Twenty-one reviews were included that examined a total of 98 potential correlates. When synthesizing all reviews, 23 correlates were found with consistent evidence for an association with a physical activity outcome. For most other potential correlates there was inconsistent evidence across reviews for associations with physical activity in young children. Although there was little overlap between the correlates identified in the umbrella review and determinants suggested by the expert panel, both confirmed the importance of socio-cultural, policy, and physical environmental factors in general. Conclusion Multiple correlates of young children's physical activity were identified. However, various methodological challenges (e.g., measurement instruments) and the large heterogeneity (e.g., study samples, correlates, and outcome measures) hindered formulating definitive conclusions. Moreover, none of the reviews reported on the interrelatedness between correlates, which would align with more holistic understandings of behavior. Our findings indicate the urgent need for establishing a common ground in definitions, assessment methods, and analytical methods to further the field of physical activity research in this tremendously important age group. Prospero Registration Number CRD42020184159.

While it has been shown that interrupting a person&rsquo, s sedentary behaviour has the potential to improve cognitive, physical and mental health, a large part of time that students spend in school is sedentary. As research has shown that approximately 80% of vocational education and training (VET) students have an unhealthy sedentary lifestyle, implementing &ldquo, sit-to-stand&rdquo, (StS) desks could interrupt sedentary behaviour and promote healthier behaviour. Therefore, the acceptability and feasibility of using such desks in the VET setting should be investigated. Using semi-structured focus group interviews analysed via deductive content analysis, the opinions of 33 students for the following topics were assessed: (1) usage of the standing option of the desks (2) reasons for standing in class (3) experienced effect of standing behind the desk, and (4) fostering future StS desks usage. Although VET students are aware of the potential benefits of using StS desks, they need to be actively stimulated and motivated by teachers to use them. In addition, time is needed to get into the habit of standing. Thus, for successful implementation of StS desks in the VET setting, all stakeholders (i.e., students, teachers, schoolboards) should be actively involved in stimulating the healthy behaviour of VET students.

A regular short physical activity break in the classroom may improve classroom behavior. The current study reports on the results of the implementation of a daily 10-min Just Dance break in the classroom. A total of 31 Dutch primary school teachers agreed to participate in the study. We collected data on the frequency of the use of the Just Dance breaks via an online registration system. Data on the long-term barriers and facilitators of the implementation were collected using two online questionnaires. In addition, we held five interviews with teachers to elucidate data on barriers and facilitators. The results show that none of the teachers maintained the Just Dance breaks on a daily basis, and only 19% (n = 6) of the teachers on a weekly basis (i.e., one to three times a week). According to all participating teachers, a lack of time was the primary barrier to implement Just Dance breaks on a daily basis. Teachers who did not maintain Just Dance breaks on a weekly basis also experienced difficulties in 1) keeping all pupils engaged during the full 10-min Just Dance break or 2) getting the pupils focused again after the Just Dance break. Teachers who maintained the Just Dance breaks on a weekly basis provided several practical recommendations for a more sustainable implementation process. This study shows that the implementation process of daily Just Dance breaks is challenging. We recommend providing teachers with professional support when implementing physical activity breaks in their daily program.

BackgroundUK and global policies recommend whole-school approaches to improve childrens’ inadequate physical activity (PA) levels. Yet, recent meta-analyses establish current interventions as ineffective due to suboptimal implementation rates and poor sustainability. To create effective interventions, which recognise schools as complex adaptive sub-systems, multi-stakeholder input is necessary. Further, to ensure ‘systems’ change, a framework is required that identifies all components of a whole-school PA approach. The study’s aim was to co-develop a whole-school PA framework using the double diamond design approach (DDDA).MethodologyFifty stakeholders engaged in a six-phase DDDA workshop undertaking tasks within same stakeholder (n= 9; UK researchers, public health specialists, active schools coordinators, headteachers, teachers, active partner schools specialists, national organisations, Sport England local delivery pilot representatives and international researchers) and mixed (n= 6) stakeholder groupings. Six draft frameworks were created before stakeholders voted for one ‘initial’ framework. Next, stakeholders reviewed the ‘initial’ framework, proposing modifications. Following the workshop, stakeholders voted on eight modifications using an online questionnaire.ResultsFollowing voting, the Creating Active Schools Framework (CAS) was designed. At the centre, ethos and practice drive school policy and vision, creating the physical and social environments in which five key stakeholder groups operate to deliver PA through seven opportunities both within and beyond school. At the top of the model, initial and in-service teacher training foster teachers’ capability, opportunity and motivation (COM-B) to deliver whole-school PA. National policy and organisations drive top-down initiatives that support or hinder whole-school PA.SummaryTo the authors’ knowledge, this is the first time practitioners, policymakers and researchers have co-designed a whole-school PA framework from initial conception. The novelty of CAS resides in identifying the multitude of interconnecting components of a whole-school adaptive sub-system; exposing the complexity required to create systems change. The framework can be used to shape future policy, research and practice to embed sustainable PA interventions within schools. To enact such change, CAS presents a potential paradigm shift, providing a map and method to guide future co-production by multiple experts of PA initiatives ‘with’ schools, while abandoning outdated traditional approaches of implementing interventions ‘on’ schools.

There are tentative indications that physical activity (PA) during school time can be beneficial for children&rsquo, s academic performance. So far, most studies have focused on the effects of moderate-to-vigorous PA, for example, in the form of energizers or extra physical education lessons. Little is known about the effects of physically active learning, in which PA is integrated with the academic content of the lessons, especially in preadolescent children. Moreover, there is a lack of knowledge regarding the enjoyment of physically active learning in this age group. Therefore, the aim of the current study was to assess the effects of integrating juggling with math practice in primary school children, on (1) multiplication memorization performance and (2) enjoyment during the math lessons. We conducted a cluster randomized controlled trial, in which 312 children (mean age 10.4 years) from nine Dutch primary schools participated. Fourteen classes were randomly assigned to either a group that learned juggling whilst practicing multiplication tables (intervention group), or to a group that practiced the same multiplication tables while sedentary (control group). Both interventions had a duration of 5 weeks and consisted of 20 short lessons (4 lessons per week, 5 to 8 min). We used mixed-model analyses to examine the effect of the intervention on multiplication memorization performance. Group (control or intervention) was used as the fixed factor, and class and school as random intercepts. Analyses were adjusted for pretest multiplication performance, age, gender, general motor skill level, physical activity behavior (PAQ-C), and academic math performance. No significant intervention effect on multiplication performance were observed. However, the math-juggling program significantly increased enjoyment of children during the math lessons. We can conclude that the intervention did not improve, but neither deteriorated children&rsquo, s math performance. The increased enjoyment in the math-juggling group can serve as an important starting point for structurally incorporating physical activities in the classroom setting.

ObjectiveTo summarise the current evidence on the effects of physical activity (PA) interventions on cognitive and academic performance in children, and formulate research priorities and recommendations.DesignSystematic review (following PRISMA guidelines) with a methodological quality assessment and an international expert panel. We based the evaluation of the consistency of the scientific evidence on the findings reported in studies rated as of high methodological quality.Data sourcesPubMed, PsycINFO, Cochrane Central, Web of Science, ERIC, and SPORTDiscus.Eligibility criteria for selecting studiesPA-intervention studies in children with at least one cognitive or academic performance assessment.ResultsEleven (19%) of 58 included intervention studies received a high-quality rating for methodological quality: four assessed effects of PA interventions on cognitive performance, six assessed effects on academic performance, and one on both. All high-quality studies contrasted the effects of additional/adapted PA activities with regular curriculum activities. For cognitive performance 10 of 21 (48%) constructs analysed showed statistically significant beneficial intervention effects of PA, while for academic performance, 15 of 25 (60%) analyses found a significant beneficial effect of PA. Across all five studies assessing PA effects on mathematics, beneficial effects were reported in six out of seven (86%) outcomes. Experts put forward 46 research questions. The most pressing research priority cluster concerned the causality of the relationship between PA and cognitive/academic performance. The remaining clusters pertained to PA characteristics, moderators and mechanisms governing the ‘PA–performance’ relationship and miscellaneous topics.ConclusionThere is currently inconclusive evidence for the beneficial effects of PA interventions on cognitive and overall academic performance in children. We conclude that there is strong evidence for beneficial effects of PA on maths performance.The expert panel confirmed that more ‘high-quality’ research is warranted. By prioritising the most important research questions and formulating recommendations we aim to guide researchers in generating high-quality evidence. Our recommendations focus on adequate control groups and sample size, the use of valid and reliable measurement instruments for physical activity and cognitive performance, measurement of compliance and data analysis.PROSPERO registration numberCRD42017082505.

Objectives Evidence suggests that physical activity is positively related to several aspects of cognitive functioning in children, among which is selective attention. To date, no information is available on the optimal frequency of physical activity on cognitive functioning in children. The current study examined the acute effects of one and two bouts of moderate-intensity physical activity on children's selective attention. Design Randomized controlled trial (ISRCTN97975679). Methods Thirty boys and twenty-six girls, aged 10–13 years, were randomly assigned to three conditions: (A) sitting all morning working on simulated school tasks; (B) one 20-min physical activity bout after 90min; and (C) two 20-min physical activity bouts, i.e. at the start and after 90min. Selective attention was assessed at five time points during the morning (i.e. at baseline and after 20, 110, 130 and 220min), using the ‘Sky Search' subtest of the ‘Test of Selective Attention in Children'. We used GEE analysis to examine differences in Sky Search scores between the three experimental conditions, adjusting for school, baseline scores, self-reported screen time and time spent in sports. Results Children who performed two 20-min bouts of moderate-intensity physical activity had significantly better Sky Search scores compared to children who performed one physical activity bout or remained seated the whole morning ( B =−0.26; 95% CI=[−0.52; −0.00]). Conclusions Our findings support the importance of repeated physical activity during the school day for beneficial effects on selective attention in children.

Both parents' and children's perception of children's weight status may be important predictors of slimming and energy-balance related behaviours, independent of children's actual weight status.; We examined the cross-sectional association of children's self-reported slimming and energy-balance related behaviours with children's (i) actual, (ii) self-perceived and (iii) parent-perceived weight status.; Data of 10- to 12-year-old European children and their parents were used. Multilevel logistic and linear regression analyses were performed, adjusting for age, gender, parental weight controlling behaviours, education, marital status and ethnicity.; Independent of their actual weight status, a higher proportion of children reported slimming when they or their parents perceived them as too fat. Children's self-perceived weight status was more strongly associated with slimming than their parents' perception or their actual weight status. Moreover, children who perceive themselves as overweight reported less physical activity and more screen time. Children whose parents perceive them as overweight reported less physical activity.; Children's own perception of their weight status appears to be more important for their self-reported slimming than their actual or their parent's perceptions of their weight status. Additionally, children's self-perceived weight status seems important in engaging more physical activity and reduces screen time.

The Daily Mile (TDM) is a school-based physical activity intervention encompassing a 15-minute run at least three times per week. This study aimed to determine (1) the effects of performing TDM for 12 weeks on Dutch primary school children&rsquo, s aerobic fitness levels and (2) if additional personal support for teachers impacted the effectiveness of TDM. Nine Dutch primary schools (n = 659 children, grades 5&ndash, 8) were allocated to a control (no TDM), intervention (12 weeks TDM) or intervention-plus (12 weeks TDM, additional personal support) group. The Shuttle Run Test (SRT) was used to assess aerobic fitness at baseline and follow-up. Data were analyzed using a multiple-imputed dataset and multilevel linear regression models to account for the clustering of students within classes and classes within schools. The regression analyses were adjusted for sex and age. Compared with the control group, significant intervention effects of TDM on SRT score were observed for the intervention group (&beta, = 1.1, 95% CI: 0.8, 1.5) and the intervention-plus group (&beta, = 0.6, 95% CI 0.3, 0.9). Additional personal support had no impact on the effectiveness of TDM. These results suggest that performing TDM at least three times per week for approximately 12 weeks increases primary school children&rsquo, s aerobic fitness. Additional personal support did not improve the effectiveness of TDM on aerobic fitness within this period. These results contribute to the body of evidence surrounding TDM, but further research is needed regarding long-term implementation of TDM.

Schools are considered ideal venues to promote physical activity (PA) in children. However, a knowledge gap exists on how to adequately integrate PA into the school day and in particular, on the preferences of children regarding additional PA in school. Therefore, the aim of our qualitative study was to gain comprehensive insight into 10&ndash, 13-year-old primary schoolchildren&rsquo, s perspectives on how to increase PA in the school setting. We conducted nine focus groups (32 girls and 20 boys) with children attending the final two grades of primary school in the Netherlands. We used inductive thematic analysis to analyze the data. The results showed that children were enthusiastic about additional PA in school. Children suggested various ways to increase PA, including more time for PA in the existing curriculum, e.g., physical education (PE), recess, and occasional activities, such as field trips or sports days, school playground adaptation, improving the content of PE, and implementing short PA breaks and physically active academic lessons. Children emphasized variation and being given a voice in their PA participation as a prerequisite to keep PA enjoyable and interesting in the long term. Finally, children mentioned the role of the teacher and making efforts to accommodate all children and their different preferences as important. Children have concrete ideas, acknowledging the challenges that accompany integrating additional PA in school. We therefore recommend actively involving children in efforts to increase school-based PA and to make &ldquo, additional PA in school&rdquo, a shared project of teachers and students.

Objective We assessed whether differences in children's sports participation and television time according to parental education were mediated by parental modeling. Moreover, we explored the differences between parental and child reports on parental sports participation and television time as potential mediators. Methods 5729 children and 5183 parents participating in the EuropeaN Energy balance Research to prevent excessive weight Gain among Youth (ENERGY-project) during 2010 in seven European countries provided information on sports participation and television time using validated self-report questionnaires. Multilevel country-specific mediation models analyzed the potential mediation effect of parental self-reports and child-reports on parental sports participation and television time. Results Significant mediation effect was found for parental self-reported television time in four countries (Greece, Hungary, The Netherlands and Slovenia), with the highest proportion for Slovenia (40%) and the lowest for Greece (21%). Child-reported parental television time showed mediation effect in Greece only. Parental self-reported sports participation showed significant mediation effect only in Greece. With child-reported parental sports participation, significant mediation was observed in Greece and Norway. Conclusions Parental behaviors appear to be important in explaining parental educational differences in children's sports participation and television time. However, child reports on parental behavior appear to be more relevant than parents' self-reports as correlates of children's own sports participation and television time.

ObjectiveTo investigate the magnitude and country-specific differences in underestimation of children’s weight status by children and their parents in Europe and to further explore its associations with family characteristics and sociodemographic factors.DesignChildren’s weight and height were objectively measured. Parental anthropometric and sociodemographic data were self-reported. Children and their parents were asked to comment on children’s weight status based on five-point Likert-type scales, ranging from ‘I am much too thin’ to ‘I am much too fat’ (children) and ‘My child’s weight is way too little’ to ‘My child’s weight is way too much’ (parents). These data were combined with children’s actual weight status, in order to assess underestimation of children’s weight status by children themselves and by their parents, respectively. Chi-square tests and multilevel logistic regression analyses were conducted to examine the aims of the current study.SettingEight European countries participating in the ENERGY (EuropeaN Energy balance Research to prevent excessive weight Gain among Youth) project.SubjectsA school-based survey among 6113 children aged 10–12 years and their parents.ResultsIn the total sample, 42·9 % of overweight/obese children and 27·6 % of parents of overweight/obese children underestimated their and their children’s weight status, respectively. A higher likelihood for this underestimation of weight status by children and their parents was observed in Eastern and Southern compared with Central/Northern countries. Overweight or obese parents (OR=1·81; 95 % CI 1·39, 2·35 and OR=1·78, 95 % CI 1·22, 2·60), parents of boys (OR=1·32; 95 % CI 1·05, 1·67) and children from overweight/obese (OR=1·60; 95 % CI 1·29, 1·98 and OR=1·76; 95 % CI 1·29, 2·41) or unemployed parents (OR=1·53; 95 % CI 1·22, 1·92) were more likely to underestimate children’s weight status.ConclusionsChildren of overweight or obese parents, those from Eastern and Southern Europe, boys, younger children and children with unemployed parents were more likely to underestimate their actual weight status. Overweight or obese parents and parents of boys were more likely to underestimate the actual weight status of their children. In obesity prevention such underestimation may be a barrier for behavioural change.

Published version of an article in the journal: PLoS One. Also available from the publisher: http://dx.doi.org/10.1371/journal.pone.0111775 Open Acces Objective: To design interventions that target energy balance-related behaviours, knowledge of primary schoolchildren’s perceptions regarding soft drink intake, fruit juice intake, breakfast consumption, TV viewing and physical activity (PA) is essential. The current study describes personal beliefs and attitudes, home- and friend-related variables regarding these behaviours across Europe. Design: Cross-sectional study in which personal, family and friend -related variables were assessed by validated questionnaires, and dichotomized as favourable versus unfavourable answers. Logistic regression analyses were conducted to estimate proportions of children giving unfavourable answers and test between-country differences. Setting: A survey in eight European countries. Subjects: A total of 7903 10–12 year old primary schoolchildren. Results: A majority of the children reported unfavourable attitudes, preferences and subjective norms regarding soft drink, fruit juice intake and TV viewing accompanied with high availability and accessibility at home. Few children reported unfavourable attitudes and preferences regarding breakfast consumption and PA. Many children reported unfavourable health beliefs regarding breakfast consumption and TV viewing. Substantial differences between countries were observed, especially for variables regarding soft drink intake, breakfast consumption and TV viewing. Conclusion: The surveyed children demonstrated favourable attitudes to some healthy behaviours (PA, breakfast intake) as well as to some unhealthy behaviours (soft drink consumption, TV viewing). Additionally, many children across Europe have personal beliefs and are exposed to social environments that are not supportive to engagement in healthy behaviours. Moreover, the large differences in personal, family and friend-related variables across Europe argue for implementing different strategies in the different European countries.

We aimed to assess the associations of person-related factors with leisure time television (TV) viewing and computer time among young adults. We analyzed self-reported TV viewing (h/week) and leisure computer time (h/week) from 475 Dutch young adults (47% male) who had participated in the Amsterdam Growth and Health Longitudinal Study at the age of 32 and 36 years. Sociodemographic factors (i.e., marital and employment status), physical factors (i.e., skin folds, aerobic fitness, neuromotor fitness, back problems), psychological factors (i.e., problem- and emotion-focused coping, personality), lifestyle (i.e., alcohol consumption, smoking, energy intake, physical activity), and self-rated health (i.e., general health status, mild health complaints) were assessed. Univariable and multivariable generalized estimating equations were performed. Male gender, higher sum of skin folds, lower values of aerobic fitness, higher rigidity, higher self-sufficiency/recalcitrance, and smoking were positively associated with TV time. Male gender, higher sum of skin folds, higher scores on self-esteem, low energy intake, and a not so good general health status were significantly associated with higher computer time. Determinants of TV viewing and computer time were not identical, suggesting that both behaviors (a) have different at-risk populations and (b) should be targeted differently.

Summary Objectives The aim of this study was to compare anthropometrics of 12- to 14-year-old Dutch adolescents attending lower levels of education in 2011 with adolescents measured in 2003. Methods We used baseline data from two trials evaluating a school-based obesity prevention programme in 2003 (randomized controlled trial with 18 schools) and in 2011 (cluster controlled trial with 29 schools). We measured adolescents' body height and weight, skin-fold thickness, and waist circumference in 2003 (n = 1000; response rate 76%) and 2011 (n = 1898; response rate 86%). We used multivariable multilevel linear or logistic regression analyses stratifying for gender, ethnicity and prevocational education track (vocational or theoretical) where appropriate. Results In boys, prevalence of overweight, waist circumference, triceps, biceps and subscapular skin-folds were significantly higher in 2011. This was also true for vocational girls, except for the subscapular skin-fold. Girls, attending the theoretical track, had a significantly larger waist circumference, but thinner subscapular and suprailiac skin-fold thickness in 2011. Conclusions The increased prevalence of overweight and obesity in Dutch adolescents attending prevocational education is worrisome. Trial registration number Current Controlled Trials ISRCTN87127361 and Current Controlled Trials ISRCTN92755979.

Purpose: This study aimed to examine the longitudinal associations of person-related factors with physical activity (PA) behavior in young adults. Methods: We analyzed longitudinal self-reported time spent in moderate-intensity PA (MPA; 4-7 METs) and vigorous-intensity PA (VPA; >7 METs) from 499 young adults (49% male) who participated in the Amsterdam Growth and Health Longitudinal Study at the age of 21, 27, 32, and 36 yr. Sociodemographic factors (i.e., marital and employment status), physical factors (i.e., skinfolds, aerobic fitness, neuromotor fitness, back problems, and general health status), psychological factors (i.e., problem and emotion focused coping, mild health complaints, and personality), and behavioral factors (i.e., alcohol consumption, smoking, and energy intake) were assessed at each time point. We performed sex-specific univariable and multivariable generalized estimating equations. Results: Men and women with higher aerobic fitness were more moderately and vigorously active. Not having paid work was associated with more MPA in both men and women. Men with part-time paid work, lower scores on dominance, higher scores on hostility, and above moderate alcohol consumption (i.e., ≥140 g of alcohol per week) were more moderately active. Divorced women and those with better physical flexibility spent more time in MPA. Men having full-time paid work, with a good general health status and nonsmokers, were more vigorously active. Women being married/living together, who had better physical flexibility, lower scores on inadequacy, higher scores on dominance, and low caloric intake (around 2000 kcal·d) were more vigorously active. Conclusion: Several sociodemographic, physical, psychological, and behavioral factors were associated with PA in Dutch young adults. Determinants were different for MPA and VPA and for men and women. © 2014 by the American College of Sports Medicine.

Objective The aim of the study was to evaluate mediating effects of energy balance-related behaviors on measures of adiposity in the Dutch Obesity Intervention in Teenagers-study (DOiT). Design and Methods DOiT was an 8-month behavioral intervention program consisting of educational and environmental components and evaluated in 18 prevocational secondary schools in the Netherlands (n = 1,108, baseline age 12.7 years, 50% girls). Outcome measures were changes in body mass index (BMI), waist circumference, and sum of skinfold thickness. Self-reported consumption of sugar-containing beverages and high caloric snacks, active transport to/from school, and screen-viewing behaviors were the hypothesized mediators. Data were collected at 0, 8, 12, and 20 months. For the data analysis, parallel process latent growth modeling was used. Results Total sugar-containing beverages consumption mediated the intervention effects on BMI (ab = −0.01, 95%CI = −0.20, −0.001). The intervention group lowered their sugar-containing beverages consumption more than controls (B = −0.14, 95%CI = −0.22, −0.11) and this, in turn, led to smaller increases in BMI. No significant mediated effect by the targeted behaviors was found for waist circumference or sum of skinfolds. Conclusions Future school-based overweight prevention interventions may target decreasing sugar-containing beverages consumption.

Purpose To evaluate and implement supportive programs, it is important to understand which cancer survivors (CSs) are participating in these programs and which motives exist for declining participation. Recently, a supportive return-to-work (RTW) program was offered to CSs with job loss. The purpose of this study was to identify factors and motives associated with (non-)participation of CSs with job loss in the RTW program. Methods In this cross-sectional study (N = 286), information on socio-demographic, health-related, psychosocial, and work-related characteristics of CSs in the program was collected. Similar data were collected from those who declined participation. Multivariable logistic regression analyses were conducted (p

Recent studies indicate that a single bout of physical exercise can have immediate positive effects on cognitive performance of children and adolescents. However, the type of exercise that affects cognitive performance the most in young adolescents is not fully understood. Therefore, this controlled study examined the acute effects of three types of 12-minute classroom-based exercise sessions on information processing speed and selective attention. The three conditions consisted of aerobic, coordination and strength exercises respectively. In particular, this study focused on the feasibility and efficiency of introducing short bouts of exercise in the classroom. One hundred and ninety five students (5th and 6th grade; 10-13 years old) participated in a double baseline within-subjects design, with students acting as their own control. Exercise type was randomly assigned to each class and acted as between-subject factor. Before and immediately after both the control and the exercise session, students performed two cognitive tests that measured information processing speed (Letter Digit Substitution Test) and selective attention (d2 Test of Attention). The results revealed that exercising at low to moderate intensity does not have an effect on the cognitive parameters tested in young adolescents. Furthermore, there were no differential effects of exercise type. The results of this study are discussed in terms of the caution which should be taken when conducting exercise sessions in a classroom setting aimed at improving cognitive performance.

This study investigates if and to what extent the Dutch Obesity Intervention in Teenagers (DOiT) program was implemented as intended and how this affected program effectiveness. We collected data at 20 prevocational education schools in the Netherlands. We assessed seven process indicators: recruitment, reach, dosage, fidelity, satisfaction, effectiveness and continuation. Data collection involved teacher questionnaires (n= 110), adolescent questionnaires and adiposity measures (n= 938). Using multi-level confirmatory factor analyses, we applied an innovative method to obtain explorative implementation index scores. The percentage of accomplished activities ranged from 9% (for 'closure meeting') up to 93% (for 'obtaining support within the school for adoption'). The percentage of lessons delivered decreased from 74 to 18% towards the end of the program. Fidelity to the teacher manual ranged from 85 to 26%. In general, teachers were satisfied with the DOiT lessons and teaching materials. Despite teachers' satisfaction with the DOiT lessons and teaching materials, degree of program implementation was lower than expected, especially towards the end of the program. Further, some evidence was found for an association between a higher implementation index score and program effectiveness, but more research is needed to test the validity of the implementation index.

Objective The aim of this study was to explore differences in weight status and energy balance behaviours according to ethnic background among adolescents across Europe. Methods A school-based survey among 10–12-year-old adolescents was conducted in seven European countries. Weight, height and waist circumference were measured; engagement in physical activity, sedentary and dietary behaviour, and sleep duration was assessed by child and parent-report. A distinction between native and non-native ethnic background was based on language spoken at home, and the parents' country of birth. Analyses were conducted with and without adjustment for parental education. Results With valid data on both indicators of ethnic background for 5149 adolescents, 7307 adolescents (52% girls; 11.6 ± 0.7 years) participated. Significantly higher prevalence of overweight, obesity, body mass index and waist circumference were observed among non-native compared with native adolescents. Non-native adolescents had less favourable behavioural patterns (sugary drinks, breakfast skipping, sport, TV and computer time, hours of sleep) with the exception of active transport to school. Similar patterns were observed for both indicators of ethnicity, and in most of the separate countries; however, in Greece, weight status indicators were better among non-native adolescents. After adjustment for parental education, most differences remained significant according to country of origin of the parents, but not according to language spoken at home. Conclusion Adolescents of native ethnicity of the country of residence have, in general, more favourable weight status indicators and energy balance-related behaviours than adolescents of non-native ethnicity across Europe.

Objective: To describe the prospective relationship between physical activity and academic performance. Data Sources: Prospective studies were identified from searches in PubMed, PsycINFO, Cochrane Central, and Sportdiscus from 1990 through 2010. Study Selection: We screened the titles and abstracts for eligibility, rated the methodological quality of the studies, and extracted data. Main Exposure: Studies had to report at least 1 physical activity or physical fitness measurement during childhood or adolescence. Main Outcome Measures: Studies had to report at least 1 academic performance or cognition measure during childhood or adolescence. Results: We identified 10 observational and 4 intervention studies. The quality score of the studies ranged from 22% to 75%. Two studies were scored as high quality. Methodological quality scores were particularly low for the reliability and validity of the measurement instruments. Based on the results of the best-evidence synthesis, we found evidence of a significant longitudinal positive relationship between physical activity and academic performance. Conclusions: Participation in physical activity is positively related to academic performance in children. Because we found only2high-quality studies, future high-quality studies areneededtoconfirmourfindings.Thesestudiesshould thoroughly examine the dose-response relationship between physical activity and academic performance as well as explanatory mechanisms for this relationship. ©2012 American Medical Association. All rights reserved.

The aim of this systematic review was to describe the prospective relationship between childhood sedentary behaviour and health indicators. We identified prospective studies from searches in PubMed, EMBASE, PsycInfo and Cochrane, from January 1989 through April 2010. Two reviewers independently screened the titles and abstracts for eligibility, rated the methodological quality of the studies, and extracted data. We identified 31 papers, examining 27 different cohorts. The quality score of the studies ranged from 38 to 88%. Nine studies were scored as high quality. According to the best evidence synthesis we found insufficient evidence for a longitudinal positive relationship between 'sedentary time'- mainly TV viewing - and body mass index (BMI) and more specific indicators of fat mass. One high quality and two low quality studies found a significant inverse relationship between sedentary time - mainly TV viewing - and aerobic fitness, leading to moderate evidence for this inverse relationship. There was insufficient evidence for a longitudinal relationship between sedentary time and blood pressure, blood lipids or bone mass. Our systematic review suggests that there is moderate evidence for a longitudinal inverse relationship between screen time and aerobic fitness during childhood. Thus there is evidence to limit screen time in young people in order to prevent low levels of fitness. The possible detrimental health effects of prolonged or excessive sitting on other health indicators needs further study.

Context Nowadays, people spend a substantial amount of time per day on sedentary behaviors and it is likely that the time spent sedentary will continue to rise. To date, there is no review of prospective studies that systematically examined the relationship between diverse sedentary behaviors and various health outcomes among adults. Purpose This review aimed to systematically review the literature as to the relationship between sedentary behaviors and health outcomes considering the methodologic quality of the studies. Evidence acquisition In February 2010, a search for prospective studies was performed in diverse electronic databases. After inclusion, in 2010, the methodologic quality of each study was assessed. A best-evidence synthesis was applied to draw conclusions. Evidence synthesis 19 studies were included, of which 14 were of high methodologic quality. Based on inconsistency in findings among the studies and lack of high-quality prospective studies, insufficient evidence was concluded for body weight–related measures, CVD risk, and endometrial cancer. Further, moderate evidence for a positive relationship between the time spent sitting and the risk for type 2 diabetes was concluded. Based on three high-quality studies, there was no evidence for a relationship between sedentary behavior and mortality from cancer, but strong evidence for all-cause and CVD mortality. Conclusions Given the trend toward increased time in sedentary behaviors, additional prospective studies of high methodologic quality are recommended to clarify the causal relationships between sedentary behavior and health outcomes. Meanwhile, evidence to date suggests that interventions aimed at reducing sedentary behavior are needed.

Background: Ample fruit and vegetable (F&V) intake has been associated with a decreased risk of chronic disease. The health-enhancing effects of increased F&V consumption, however, would be even more apparent if the increased F&V consumption additionally led to a lower intake of unhealthy, high calorie snacks. Therefore, the present study aimed to investigate whether a primary school-based intervention (the Dutch Schoolgruiten Project) that promoted F&V intake could additionally reduce the intake of unhealthy, high calorie snacks during school breaks. Methods: The study applied a longitudinal design with baseline and two follow-up measurements. Children were aged 9–10 years old at baseline; 705 children were included. The main strategy was a F&V scheme that improved the availability, accessibility and exposure to F&V at school by providing one serving of fruit or vegetables twice a week at no cost. The amounts of F&V and unhealthy snacks for consumption at school were measured using a single-item question included in a questionnaire. Multilevel autoregressive logistic regression models with a three-level structure (school, child and time) were used to assess the effect of the intervention on both F&V and unhealthy snack consumption. Results: The children of the intervention group brought FV 1.90] and brought fewer unhealthy snacks (OR = 0.56, 95% CI = 0.34; 0.92). Conclusion: The present study provides some evidence that the Schoolgruiten intervention effect on F&V intake also reduced unhealthy snacking during school breaks.

To determine whether a multicomponent health promotion intervention for Dutch adolescents (defined as persons between 12 and 14 years of age) would be successful in influencing body composition and dietary and physical activity behavior in both the short and long terms.Randomized controlled trial.Ten intervention and 8 control prevocational secondary schools.A total of 1108 adolescents (mean age, 12.7 years). Intervention An interdisciplinary program with an adapted curriculum for 11 lessons in biology and physical education and environmental change options.Body height and weight, waist circumference, 4 skinfold thickness measurements, and dietary and physical activity behavior data.Multilevel analyses showed that the intervention remained effective in preventing unfavorable increases in important measures of body composition after 20-month follow-up in girls (biceps skinfold and sum of 4 skinfolds) and boys (triceps, biceps, and subscapular skinfolds). Consumption of sugar-containing beverages was significantly lower in intervention schools both after intervention (boys: -287 mL/d; 95% confidence interval [CI], -527 to -47; girls: -249; -400 to -98) and at 12-month follow-up (boys: -233; -371 to -95; girls: -271; -390 to -153). For boys, screen-viewing behavior was significantly lower in the intervention group after 20 months (-25 min/d; 95% CI, -50 to -0.3). No significant intervention effects on consumption of snacks or active commuting to school were found.The Dutch Obesity Intervention in Teenagers program resulted in beneficial effects on the sum of skinfold thickness measurements in girls and consumption of sugar-containing beverages in both boys and girls in both the short and long terms.

Overweight and obesity in youth are important public health concerns and are of particular interest because of possible long-term associations with adult weight status and morbidity. The aim of this study was to systematically review the literature and update evidence concerning persistence of childhood overweight. A computerized bibliographical search--restricted to studies with a prospective or retrospective longitudinal design--was conducted. Two authors independently extracted data and assessed the methodological quality of the included studies in four dimensions (i) study population and participation rate; (ii) study attrition; (iii) data collection and (iv) data analysis. Conclusions were based on a rating system of three levels of evidence. A total of 25 publications were selected for inclusion in this review. According to a methodological quality assessment, 13 studies were considered to be of high quality. The majority of these high-quality studies were published after 2001, indicating that recently published data, in particular, provide us with reliable information. All included studies consistently report an increased risk of overweight and obese youth becoming overweight adults, suggesting that the likelihood of persistence of overweight into adulthood is moderate for overweight and obese youth. However, predictive values varied considerably. Limiting aspects with respect to generalizability and methodological issues are discussed.

The purpose of this study was to investigate whether perceived parenting practices and parenting style dimensions (strictness and involvement) are associated with adolescents' consumption of sugar-sweetened beverages. In this cross-sectional study, secondary school students (n = 383, mean age 13.5 years) completed a self-administered questionnaire on their consumption of sugar-sweetened beverages, attitude, social influences, self-efficacy, habit strength, food-related parenting practices and the general parenting style dimensions of 'strictness' and 'involvement'. Data were analyzed using multiple linear regression analyses. More restrictive parenting practices were associated with lower consumption of sugar-sweetened beverages (beta = -38.0 ml; 95% CI = -48.1, -28.0). This association was highly mediated ( approximately 55%) by attitude, self-efficacy and modeling from parents. Nevertheless, a significant direct effect remained (beta = -17.1 ml; 95% CI = -27.2, -6.90). Interactions between perceived parenting style and parenting practices showed that the association between parenting practices and sugar-sweetened beverage consumption was stronger among adolescents who perceived their parents as being moderately strict and highly involved. Parents influence their children's sugar-sweetened beverage consumption and should therefore be involved in interventions aimed at changing dietary behaviors. Interventions aimed at the promotion of healthy parenting practices will improve when they are tailored to the general parenting style of the participants.

Objective To determine whether a multicomponent health promotion intervention for Dutch adolescents would be successful in influencing body composition and aerobic fitness. Design Randomized controlled trial. Setting Ten intervention and 8 control prevocational secondary schools. Participants A total of 978 adolescents (mean age, 12.7 years). Intervention An interdisciplinary multicomponent intervention program with an adapted curriculum for 11 biology and physical education lessons and environmental change options, including additional lessons on physical education and advice on the school canteen selection. Main Outcome Measures Body height and weight, hip and waist circumference, 4 skinfold thickness measurements, and aerobic fitness. Results Multilevel analyses showed significant differences in changes after the 8-month intervention period in favor of the intervention group with regard to hip circumference (mean difference, 0.53 cm; 95% confidence interval, 0.07 to 0.98) and sum of skinfolds among girls (mean difference, −2.31 mm; 95% confidence interval, −4.34 to −0.28). In boys, the intervention resulted in a significant difference in waist circumference (mean difference, −0.57 cm; 95% confidence interval, −1.10 to −0.05). No significant intervention effects were found related to aerobic fitness. Conclusions The multicomponent Dutch Obesity Intervention in Teenagers program positively influenced several measures of body composition among both girls and boys. Our results indicate that secondary prevocational school curriculum changes may contribute to excessive weight gain prevention among adolescents.

Objectives To identify the biological, socio-demographic, work-related and lifestyle determinants of physical activity in young adult women. Design Prospective cohort study. Methods Self-reported data from 11,695 participants (aged 22–27 years in 2000) in the Australian Longitudinal Study on Women's Health were collected over 9 years in 2000, 2003, 2006 and 2009. Generalised Estimating Equations were used to examine univariable and multivariable associations of body mass index, country of birth, area of residence, education, marital status, number of children, occupational status, working hours, smoking, alcohol intake, and stress with physical activity status (active, ≥600 MET·min/week; or inactive, Results All variables were significantly associated with physical activity in univariable models. In the multivariable model, the lowest odds of being active (compared with the relevant reference categories) were for women who: were born in Asia (OR = 0.53), had less than 12 years of education (OR = 0.79), were married (OR = 0.66) or in a de facto relationship (OR = 0.79), had at least one child (OR ranging from 0.67 to 0.69), and were classified as non (OR = 0.66) or rare drinkers (OR = 0.79). Conclusions These results are among the first to confirm the biological, socio-demographic, work-related and lifestyle determinants of physical activity in women in their twenties and early thirties. These findings may be used to inform and improve the development of strategies, and to identify target groups most in need of intervention effort.

ObjectiveTo explore the influences of migration to a Western country on obesity and related risk factors by comparing measures of body composition and energy balance-related behaviours between Turkish adolescents in Turkey (TR-TR) and adolescents from Turkish immigrant ethnicity in the Netherlands (TR-NL).DesignCross-sectional survey or baseline intervention data from six Dutch school-based studies and one Turkish study.SettingPrimary and secondary schools.SubjectsA total of 915 (49 % girls; mean age 13·1 (sd 0·8) years) TR-TR adolescents and 433 (51 % girls; mean age 11·7 (sd 1·3) years) TR-NL adolescents were included. Outcome measures were self-reported sugar-containing beverage consumption, fruit and vegetable intake, screen time, physical activity, measured body height and weight, BMI, waist and hip circumferences, and skinfold thicknesses.ResultsOur data showed that more TR-NL adolescents were overweight (31 % v. 26 %) and obese (9 % v. 6 %) and had significantly higher mean BMI (21·1 v. 20·0 kg/m2), waist circumference (72·2 v. 71·3 cm) and suprailiac skinfold thickness (19·8 v. 13·1 mm) than TR-TR adolescents. TR-NL adolescents reported significantly higher sugar-containing beverage consumption (1173 v. 115 ml/d), less fruit and vegetable intake (295 v. 647 g/d), less screen time (253 v. 467 min/d) and higher physical activity levels (61 v. 27 min/d) than TR-TR adolescents.ConclusionsImmigrant adolescents in the Netherlands were more often overweight and had a less favourable dietary pattern than their peers in Turkey, while their physical activity and screen time patterns were more favourable. These results suggest that adolescents from Turkish immigrant ethnicity in the Netherlands have adopted lifestyles towards the host culture.

Objective To investigate the relationship between physical activity and lung cancer among smokers and whether this relationship differed according to physical activity intensity, smoking status, and gender. Design Meta-analysis. Methods A computerized bibliographical search was conducted in five databases. Study inclusion criteria were: (i) the study population was not diagnosed with lung cancer at baseline; (ii) the study provided information concerning the effect size of physical activity on the risk of developing lung cancer in smokers; and (iii) the study distinguished different physical activity intensity levels. Two authors independently extracted data and assessed the methodological quality. Pooled rate ratios (RR) were calculated for all data, and for subgroups of physical activity intensity, smoking status, and gender. Results Pooled RRs of 7 cohort studies showed that physical activity was associated with a reduced risk of lung cancer in smokers (RR = 0.82, 95% CI = 0.77; 0.87). We did not find clear dose–response relationship regarding exercise or smoking intensity, i.e. high levels of physical activity did not show a higher risk reduction than moderate physical activity levels, and the association between physical activity and risk reduction did not differ between heavy and light smokers. The reduced risk associated with physical activity was greater in women than in men (p = 0.03), but this finding was based on only one study that reported data on women. Conclusions Results of this meta-analysis indicate that leisure time physical activity is associated with reduced risk of developing lung cancer among smokers. Future studies should provide insight into a potential dose–response relationship, and should use reliable and valid physical activity measurements.

Background The Dutch Obesity Intervention in Teenagers (DOiT) programme is an evidence-based obesity prevention programme tailored to adolescents attending the first two years of prevocational education in the Netherlands. The initial programme showed promising results during an effectiveness trial. The programme was adapted and prepared for nationwide dissemination. To gain more insight into the process of translating evidence-based approaches into ‘real world’ (i.e., ‘natural’) conditions, our research aims were to evaluate the impact of the DOiT-implementation programme on adolescents’ adiposity and energy balance-related behaviours during natural dissemination and to explore the mediating and moderating factors underlying the DOiT intervention effects. Methods We conducted a cluster-controlled implementation trial with 20 voluntary intervention schools (n=1002 adolescents) and 9 comparable control schools (n = 484 adolescents). We measured adolescents’ body height and weight, skinfold thicknesses, and waist circumference. We assessed adolescents’ dietary and physical activity behaviours by means of self-report. Data were collected at baseline and at 20-months follow-up. We used multivariable multilevel linear or logistic regression analyses to evaluate the intervention effects and to test the hypothesised behavioural mediating factors. We checked for potential effect modification by gender, ethnicity and education level. Results We found no significant intervention effects on any of the adiposity measures or behavioural outcomes. Furthermore, we found no mediating effects by any of the hypothesised behavioural mediators. Stratified analyses for gender showed that the intervention was effective in reducing sugar-containing beverage consumption in girls (B = -188.2 ml/day; 95% CI = -344.0; -32.3). In boys, we found a significant positive intervention effect on breakfast frequency (B = 0.29 days/week; 95% CI = 0.01; 0.58). Stratified analyses for education level showed an adverse intervention effect (B = 0.09; 95% CI = 0.02; 0.16) on BMI z-scores for adolescents attending the vocational education track. Conclusions Although not successful in changing adolescents’ adiposity, the DOiT-implementation programme had some beneficial effects on specific obesity-related behaviours in subgroups. This study underlines the difficulty of translating intervention effectiveness in controlled settings to real world contexts. Adaptations to the implementation strategy are needed in order to promote implementation as intended by the teachers. Trial registration Current Controlled Trials ISRCTN92755979. Electronic supplementary material The online version of this article (doi:10.1186/s12966-014-0158-0) contains supplementary material, which is available to authorized users.

Background Parents and their parenting practices play an important role in shaping their children’s environment and energy-balance related behaviours (EBRBs). Measurement of parenting practices can be parent- or child-informed, however not much is known about agreement between parent and child perspectives. This study aimed to assess agreement between parent and child reports on parental practices regarding EBRBs across different countries in Europe and to identify correlates of agreement. Methods Within the ENERGY-project, a cross-sectional survey was conducted among 10–12 year old children and their parents in eight European countries. Both children and parents filled in a questionnaire on 14 parental practices regarding five different EBRBs (i.e. soft drink, fruit juice and breakfast consumption, sports activity and watching TV) and socio-demographic characteristics. Children’s anthropometric measurements were taken at school. We calculated percentages of agreement between children and their parents and weighted kappa statistics (for ordinal variables) per practice and country and assessed factors associated with agreement using multilevel linear regression. Results Reports of 6425 children and their parents were available for analysis. Overall mean agreement between parent and child reports was 43% and varied little among countries. The lowest agreement was found for questions assessing joint parent–child activities, such as sports (27%; Kappa (κ) = 0.14) or watching TV (30%;κ = 0.17), and for parental allowance of the child to have soft drinks (32%;κ = 0.24) or fruit juices (32%;κ = 0.19), or to watch TV (27%;κ = 0.17). Having breakfast products available at home or having a TV in the child’s bedroom were the only practices with moderate to good agreement (>60%;κ = 0.06 and 0.77, respectively). In general, agreement was lower for boys, younger children, younger parents, parents with less than 14 years of education, single parents, parents with a higher self-reported body mass index and parents who perceived their child to be underweight. Conclusions Parents and children perceive parental practices regarding dietary, physical activity and sedentary behaviours differently in all parts of Europe, with considerable variation across specific practices and countries. Therefore, future studies should assess both, parents and children’s view on parental practices. Electronic supplementary material The online version of this article (doi:10.1186/1471-2458-14-918) contains supplementary material, which is available to authorized users.

Background To explore differences in personal and home environmental factors that are regarded as determinants of energy balance-related behaviors (EBRBs) according to parental education and ethnic background among 10–12 year old schoolchildren across Europe. Methods A school-based survey among 10–12 year olds was conducted in eight countries across Europe. A range of personal and home environment variables relevant for soft drink consumption, daily breakfast, sport participation and TV time was assessed by means of child report. Personal factors included attitude, health beliefs, and preference/liking. Home environment factors included parental subjective norm, modeling, support, practices and home availability. Children were classified based on parental education (i.e., low vs. high) and ethnic background (i.e., native vs. non-native). Data from 6018 children originating from 83 schools were included in the analyses. Results Multilevel logistic regression analyses showed that the majority of the factors tested –and especially home environment variables- were more favorable among children from higher educated parents and from native ethnicity. None of the personal and home environment factors was found to be more favorable among children from lower educated parents or non-native ethnicity. Conclusions The present study indicates that schoolchildren from lower educated and non-native parents across Europe have EBRB-related beliefs and are exposed to home environments that are less favorable for engagement in healthy EBRBs.

BackgroundIn affluent countries, children from non-native ethnicity have in general less favourable body composition indicators and energy balance-related behaviors (EBRBs) than children from native ethnicity. However, differences between countries have been reported.Methodology/principal findingsA school-based survey among 10-12 years old children was conducted in seven European countries with a standardized protocol. Weight, height and waist circumference were measured; engagement in EBRBs was self-reported. For those countries with significant ethnic differences in body composition (Greece and the Netherlands), multilevel mediation analyses were conducted, to test the mediating effect of the EBRBs in the association between ethnic background and body composition indicators. Analyses were adjusted for gender and age, and for parental education in a later step. Partial mediation was found for sugared drinks intake and sleep duration in the Greek sample, and breakfast in the Dutch sample. A suppression effect was found for engagement in sports activites in the Greek sample.Conclusions/significanceEthnic differences in children's body composition were partially mediated by differences in breakfast skipping in the Netherlands and sugared drinks intake, sports participation and sleep duration in Greece.

Background Sitting is associated with health risks. Factors that influence sitting are however not well understood. The aim was to examine the biological, socio-demographic, work-related and lifestyle determinants of sitting time (including during transport, work and leisure) in young adult Australian women. Methods Self-reported data from 11,676 participants (aged 22–27 years in 2000) in the Australian Longitudinal Study on Women’s Health were collected over 9 years in 2000, 2003, 2006 and 2009. Generalised Estimating Equations were used to examine univariable and multivariable associations of body mass index (BMI), country of birth, area of residence, education, marital status, number of children, occupational status, working hours, physical activity, smoking, alcohol intake and stress with week- and weekend-day sitting time. Results Compared with women in the respective referent categories, (1) women with higher BMI, those born in Asia, those with less than University level education, doing white collar work, working 41–48 hours a week, current smokers, non, rare or risky/high risk drinkers and those being somewhat stressed had significantly higher sitting time; and (2) women living in rural and remote areas, partnered women, those with children, those without a paid job and blue collar workers, those working less than 34 hours a week, and active women had significantly lower sitting time. Conclusions Among young adult Australian women, those with higher BMI, those born in Asia, those with higher level occupations and long working hours, were most at risk of higher sitting time. These results can be used to identify at-risk groups and inform intervention development.

Background The evidence-based Dutch Obesity Intervention in Teenagers (DOiT) program is a school-based obesity prevention program for 12 to 14-year olds attending the first two years of prevocational education. This paper describes the study protocol applied to evaluate (a) the nationwide dissemination process of DOiT in the Netherlands, and (b) the relationship between quality of implementation and effectiveness during nationwide dissemination of the program in the Netherlands. Methods In order to explore facilitating factors and barriers for dissemination of DOiT, we monitored the process of adoption, implementation and continuation of the DOiT program among 20 prevocational schools in the Netherlands. The study was an observational study using qualitative (i.e. semi-structured interviews) and quantitative methods (i.e. questionnaires and logbooks). Eight process indicators were assessed: recruitment, context, reach, dosage, fidelity, satisfaction, effectiveness and continuation. All teachers, students and parents involved in the implementation of the program were invited to participate in the study. As part of the process evaluation, a cluster-controlled trial with ten control schools was conducted to evaluate the effectiveness of the program on students’ anthropometry and energy balance-related behaviours and its association with quality of implementation. Discussion The identified impeding and facilitating factors will contribute to an adjusted strategy promoting adoption, implementation and continuation of the DOiT program to ensure optimal use and, thereby, prevention of obesity in Dutch adolescents. Trial registration Current Controlled Trials ISRCTN92755979.

Published version of an article in the journal: International Journal of Behavioral Nutrition and Physical Activity. Also available from the publisher at: http://dx.doi.org/10.1186/1479-5868-10-5 Open access Background: Recent research and literature reviews show that, among schoolchildren, some specific energy balance-related behaviors (EBRBs) are relevant for overweight and obesity prevention. It is also well known that the prevalence of overweight and obesity is considerably higher among schoolchildren from lower socio-economic backgrounds. This study examines whether sugared drinks intake, physical activity, screen time and usual sleep duration cluster in reliable and meaningful ways among European children, and whether the identified clusters could be characterized by parental education. Methods: The cross-sectional study comprised a total of 5284 children (46% male), from seven European countries participating in the ENERGY-project (" EuropeaN Energy balance Research to prevent excessive weight Gain among Youth"). Information on sugared drinks intake, physical activity, screen time and usual sleep duration was obtained using validated self-report questionnaires. Based on these behaviors, gender-specific cluster analysis was performed. Associations with parental education were identified using chi-square tests and odds ratios. Results: Five meaningful and stable clusters were found for both genders. The cluster with high physical activity level showed the highest proportion of participants with highly educated parents, while clusters with high sugared drinks consumption, high screen time and low sleep duration were more prevalent in the group with lower educated parents. Odds ratio showed that children with lower educated parents were less likely to be allocated in the active cluster and more likely to be allocated in the low activity/sedentary pattern cluster. Conclusions: Children with lower educated parents seemed to be more likely to present unhealthier EBRBs clustering, mainly characterized by their self-reported time spent on physical activity and screen viewing. Therefore, special focus should be given to lower educated parents and their children in order to develop effective primary prevention strategies.

Published version from the journal: BMC Research Notes. Also available from BMC: http://dx.doi.org/10.1186/1756-0500-5-434 Open Access Background: Insight in parental energy balance-related behaviours, their determinants and parenting practices are important to inform childhood obesity prevention. Therefore, reliable and valid tools to measure these variables in large-scale population research are needed. The objective of the current study was to examine the test-retest reliability and construct validity of the parent questionnaire used in the ENERGY-project, assessing parental energy balance-related behaviours, their determinants, and parenting practices among parents of 10–12 year old children. Findings: We collected data among parents (n=316 in the test-retest reliability study; n=109 in the construct validity study) of 10–12 year-old children in six European countries, i.e. Belgium, Greece, Hungary, the Netherlands, Norway, and Spain. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC) and percentage agreement comparing scores from two measurements, administered one week apart. To assess construct validity, the agreement between questionnaire responses and a subsequent interview was assessed using ICC and percentage agreement. All but one item showed good to excellent test-retest reliability as indicated by ICCs>.60 or percentage agreement≥75%. Construct validity appeared to be good to excellent for 92 out of 121 items, as indicated by ICCs>.60 or percentage agreement≥75%. From the other 29 items, construct validity was moderate for 24 and poor for 5 items. Conclusions: The reliability and construct validity of the items of the ENERGY-parent questionnaire on multiple energy balance-related behaviours, their potential determinants, and parenting practices appears to be good. Based on the results of the validity study, we strongly recommend adapting parts of the ENERGY-parent questionnaire if used in future research.

Background Screen time has been associated with pediatric overweight. However, it is unclear whether overweight predicts or is predicted by excessive amounts of screen time. The aim of this study was to examine the direction of the association between screen time and body fatness in Dutch adolescents. Methods Longitudinal data of 465 Dutch adolescents (mean age at baseline 13 years, 53% boys) was used. Body fatness (objectively measured BMI, four skin folds and waist- and hip circumference), self-reported time spent watching TV and computer use, and aerobic fitness (shuttle run test) were assessed in all participants at three time points during 12 months. Multi-level linear autoregressive analyses was used to examine whether screen time predicted body fatness in the following time period and whether body fatness predicted screen time. Analyses were performed for boys and girls separately and adjusted for ethnicity and aerobic fitness. Results Time spent TV viewing did predict changes in BMI and hip circumference in boys, but not in girls, in the subsequent period. Computer time significantly predicted increases in skinfolds in boys and girls and increases in BMI in girls. Body fatness did not predict any changes in screen time. Conclusion The present study only partly supports the widely posited hypothesis that higher levels of screen time cause increases in body fatness. In addition, this study demonstrates that high levels of body fatness do not predict increases in screen time.

Published version of an article from the journal: International Journal of Behavioral Nutrition and Physical Activity. Also available from BMC: http://dx.doi.org/10.1186/1479-5868-9-136 Open Access Background To date, most research on obesogenic environments facing school children has focused on physical and socio-cultural environments. The role of economic factors has been investigated to a much lesser extent. Our objective was to explore the association of micro-level economic factors and incentives with sports activities and intake of soft drinks and fruit juice in 10-12 year-old school children across Europe, and to explore price sensitivity in children’s soft drink consumption and correlates of this price sensitivity. Methods Data for the study originate from a cross-sectional survey undertaken in seven European countries (Belgium, Greece, Hungary, Netherlands, Norway, Slovenia and Spain) in 2010 among 10-12 year-old school children and their parents. In total, 7234 child questionnaires and 6002 parent questionnaires were completed. The child questionnaire included questions addressing self-reported weekly intake of soft drinks and fruit juices and time spent on sports activities, perception of parental support for sports activities, use of pocket money for soft drinks and perceived price responsiveness. Parent questionnaires included questions addressing the role of budget and price considerations in decisions regarding children’s sports activities, soft drink consumption, home practices and rules and socio-demographic background variables. Data were analysed using multiple linear regression and discrete-choice (ordered probit) modelling. Results Economic factors were found to be associated with children’s sports participation and sugary drink consumption, explaining 27% of the variation in time for sports activities, and 27% and 12% of the variation in the children’s soft drink and juice consumption, respectively. Parents’ financial support was found to be an important correlate (Beta =0.419) of children’s sports activities. Children’s pocket money was a strong correlate (Beta =21.034) of soft drink consumption. The majority of the responding children reported to expect that significantly higher prices of soft drinks would lead them to buy less soft drinks with their own pocket money, but a majority of parents did not expect higher soft drink prices to reduce their children’s soft drink consumption. Conclusions We conclude that economic factors, especially parents’ financial support and amount of pocket money, appear to be of importance for children’s sports participation and soft drink consumption, respectively. Keywords: Children; Obesogenic environment; Economic incentives; Sports activity; Soft drinks; Price responsiveness

BACKGROUND: The association between objectively assessed sedentary time and metabolic risk factors in childhood have rarely been studied. Therefore, we examined the independent relationship between objectively assessed and self-rated sedentary time and indicators of metabolic health in Dutch and Hungarian 10-12 year olds. METHODOLOGY/PRINCIPAL FINDINGS: We performed a cross-sectional survey in primary schools. Participants were Dutch and Hungarian girls (n = 73, aged 12.2 ± 0.6 years, 18% overweight/obese) and boys (n = 69, aged 12.2 ± 0.7 years, 38% overweight/obese). Sedentary time and physical activity were assessed by the Actigraph accelerometer. TV and PC time were assessed by self-report. Adiposity indicators included body weight, height, and waist circumference (WC). Fasting plasma glucose, C-peptide, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and triglycerides were determined in capillary blood and summed into a metabolic risk score. Linear regression analyses were adjusted for physical activity, number of sedentary bouts and WC. Children spent on average 7.6 hours of their daily waking time in sedentary behavior and self-reported 116 ± 64 min/day watching TV and 85 ± 57 min/day using the computer. Comparing the 1(st) and 4(th) quartile of objectively assessed sedentary time, C-Peptide levels, WC and BMI were significantly higher in the most sedentary quartile, while the difference in metabolic risk score was borderline significant (p = 0.09). Comparing the 1(st) and 4(th) quartile of TV time, BMI was significantly higher in the most sedentary quartile, while the difference in WC score was borderline significant (p = 0.06). In the adjusted linear regression analysis we found no significant association of sedentary time with metabolic risk. CONCLUSIONS/SIGNIFICANCE: Although BMI and WC were higher in the most sedentary versus the least sedentary children; we found no further evidence that more sedentary children were at increased metabolic risk.

Background Obesity treatment is by large ineffective long term, and more emphasis on the prevention of excessive weight gain in childhood and adolescence is warranted. To inform energy balance related behaviour (EBRB) change interventions, insight in the potential personal, family and school environmental correlates of these behaviours is needed. Studies on such multilevel correlates of EBRB among schoolchildren in Europe are lacking. The ENERGY survey aims to (1) provide up-to-date prevalence rates of measured overweight, obesity, self-reported engagement in EBRBs, and objective accelerometer-based assessment of physical activity and sedentary behaviour and blood-sample biomarkers of metabolic function in countries in different regions of Europe, (2) to identify personal, family and school environmental correlates of these EBRBs. This paper describes the design, methodology and protocol of the survey. Method/Design A school-based cross-sectional survey was carried out in 2010 in seven different European countries; Belgium, Greece, Hungary, the Netherlands, Norway, Slovenia, and Spain. The survey included measurements of anthropometrics, child, parent and school-staff questionnaires, and school observations to measure and assess outcomes (i.e. height, weight, and waist circumference), EBRBs and potential personal, family and school environmental correlates of these behaviours including the social-cultural, physical, political, and economic environmental factors. In addition, a selection of countries conducted accelerometer measurements to objectively assess physical activity and sedentary behaviour, and collected blood samples to assess several biomarkers of metabolic function. Discussion The ENERGY survey is a comprehensive cross-sectional study measuring anthropometrics and biomarkers as well as assessing a range of EBRBs and their potential correlates at the personal, family and school level, among 10-12 year old children in seven European countries. This study will result in a unique dataset, enabling cross country comparisons in overweight, obesity, risk behaviours for these conditions as well as the correlates of engagement in these risk behaviours.

Objective The aim of this systematic review was to summarise and update the existing literature on determinants of physical activity and sedentary behaviour in young people, considering the methodological quality of the studies. Methods: Prospective studies were identifi ed from searches in PubMed and PsycINFO, from April 2004 through November 2010. The authors included studies investigating the association between determinants of overall physical (in)activity and/or sedentary behaviour in healthy children or adolescents. When a determinant was investigated for its association with physical (in) activity and sedentary behaviour assessed between ages of 4-12, or mean age ≤12, it was classifi ed as 'child determinant'. When a determinant was investigated for its association with physical activity and sedentary behaviour assessed between ages of 13-18 or mean age >12, it was classifi ed as 'adolescent determinant'. Included articles were scored on their methodological quality and a best-evidence synthesis was applied to summarise the results. Results: The authors identifi ed 30 papers, of which seven were of high methodological quality. Intention was found as a determinant of children's physical activity. Determinants of adolescents' physical activity were age (ie, older children were more active), ethnicity (ie, being of African-American descent determined being less physically active) and planning. The authors found insuffi cient evidence for determinants of sedentary behaviour. Conclusion: Studies on determinants of physical activity and sedentary behaviour were in general of poor methodological quality. To develop long-term effective interventions that increase physical activity and decrease time spent in sedentary behaviours in young people, we need more high quality prospective evidence on the determinants of these behaviours.