OBJECTIVE:The primary aim of this study is to evaluate the feasibility of a proposed intervention designed to support the daily movement practices and fostering joy of movement in Danish kindergartens, as well as the implementation strategies intended to facilitate adoption. Additionally, the feasibility of the planned measurement and procedures for a future effectiveness study will be examined. METHODS:The study uses a mixed-methods design to examine the feasibility of the intervention and the evaluation design. The planned duration of the intervention period is 10 weeks. The intervention consists of multiple integrated components co-designed with pedagogical staff, leaders, experts in kindergarten movement culture, and a team of researchers, to collectively support the daily movement practice in kindergartens. Alongside the intervention components, tailored strategies are developed to facilitate adoption and implementation. The intervention elements are categorized into four main types: 1) Formal establishment of the project; 2) Components of physical activity integrated in existing structures in the kindergarten; 3) Organizational and staff training; 4) Inspirational materials, tools and exemplary plans. DISCUSSION:The use of a co-design approach in close collaboration between kindergartens, experts, and a team of researchers will ensure contextual relevance and shared ownership. This approach is expected to enhance acceptability, feasibility, and sustainability of the intervention. The mixed-methods evaluation design, use of theoretical implementation frameworks, and tailored strategies further strengthen the study. The findings from this feasibility study will inform the refinement of the final intervention and guide the planning of a forthcoming effectiveness study.

Physical activity (PA) should be an essential part of all children’s lives, as it can promote physical and mental health, enhance general well-being, and positively impact learning outcomes. Schools offer an ideal setting to encourage physical activity during the school day, as nearly all children attend school. However, schools present a complex environment for implementing PA, and sedentary behavior is common in classroom teaching. This study explores the feasibility of two types of school-based physical activity interventions: one based on research in exercise and cognition (Run, Jump & Fun) and another grounded in embodied learning (Move & Learn). Run, Jump & Fun can be conceptualized as extra non-curricular physical activity implemented into the school day while Move & Learn is integrated into curricular time. The 8-week study involved third-grade students and their teachers from seven schools, with educational strategies applied to support adoption. Quantitative and qualitative data were collected before, during, and after the 8-week period. The results indicated that both interventions were feasible to implement, leading to a series of recommendations for further refinement. These recommendations can guide the development of future school-based PA interventions and inspire other researchers to assess and improve their implementation strategies.

Background Reading and spelling skills are important abilities to acquire for later success in school and therefore it is highly relevant to examine strategies of facilitating these academic skills. Physical activity integrated with the learning sessions or physical activity added but not integrated with the learning sessions has been identified as possible strategies. Objective To identify, categorize and examine the characteristics and effects of interventions investigating the effect of physical activity on children’s early reading skills. Design This systematic review follows the PRISMA guidelines. Studies were separated into two categories based on whether physical activity integrates academic content or not, i.e., 1) low integration interventions or 2) high integration interventions. Additionally, high integration interventions were further subgrouped based on the congruency of the activity (i.e., whether the movement supported the learning content). Low integration interventions were subgrouped based on the complexity of the activity (i.e., if the physical activity was cognitively/coordinatively demanding or not). Study quality was assessed, and effects were summarized narratively for each category. Furthermore, a meta-analysis was conducted to quantify both types of interventions. Only studies involving children with an intervention investigating the long-term effects of physical activity on prereading, word recognition, and spelling skills were included. Data Sources PubMed, Web of Science, PsychINFO, Linguistics and Language Behavior Abstracts, ERIC and SportDiscuss. Results Twenty-three studies were identified and categorized into two groups (thirteen high integration interventions and ten low integration interventions). Across outcome measures, eight of the thirteen high-integration intervention studies reported statistically significant effects on at least one measure of prereading, word recognition, or spelling skills favoring the intervention. In contrast, only two out of ten studies categorized as low integration interventions reported a statistically significant effect. Multilevel meta-analysis showed an insignificant average random-effects model size of Hedges’ g = 0.03 (95% CI: -0.02, 0.09) for low integration and a significant effect size of g = 0.69 (95% CI: 0.12, 1.26) for high integration interventions. The distinction between low and high complexity within the low integration group, and between levels of congruency in high integration interventions, revealed no significant differences between these subgroups. Conclusions Results from the present review and meta-analysis suggest that the integration of physical activity into the classroom, using activities with a close temporal connection to the academic task (i.e., high integration interventions), appears to be an effective strategy to improve children’s word recognition and spelling skills. Due to the limited number and heterogeneity across studies included these findings call for additional studies to clarify specific characteristics of the physical activity needed to support the process of learning to read and spell for children.

It is internationally recognized to use clinical decision limits (CDL) when interpreting the lipid levels in both adults and children, even though the evidence for children is scarce. The purpose of this study is to describe how lipid levels progress in healthy Danish children ages 5 to 17 years. This study is based on the Childhood Health, Activity, and Motor Performance School Study Denmark (CHAMPS-study DK) consisting of 1456 observations of schoolchildren aged 5 to 17 years. Participants have been tested for blood levels of total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, and remnant cholesterol levels are calculated. Finally, sex-specific percentile reference curves are presented. Percentile reference curves stratified by sex were generated for all cholesterols and showed that the total cholesterol level peaks at 4.32 mmol/l in 10-year-old boys and 4.46 mmol/l in nine-year-old girls. HDL levels in boys peak at 1.72 mmol/l in nine-year-old boys. HDL levels in girls and LDL levels in both sexes are nearly constant. Triglycerides kept rising to the age of 17 years in both sexes and remnant cholesterol decreased from age 5 to 17 years in both sexes. BMI z-score adjustment revealed no significant association with total cholesterol in both sexes but a significant association between HDL, LDL, triglycerides, and remnant cholesterol. This study is the first to generate percentile reference curves for blood levels of total cholesterol, LDL, HDL, triglycerides, and remnant cholesterol in a cohort of healthy Danish children aged 5 to 17 years.

ABSTRACT Introduction Physical activity (PA) interventions in schools can improve children’s overall PA levels and positively affect academic performance. However, implementing PA during the school day can be challenging in the complex school setting. Many school-based PA studies do not present their interventions’ design processes, although this knowledge is important to replicate the intervention. Purpose This article aims to provide insights into the collaborative design process of the two PA interventions for third-grade pupils of the ACTIVE SCHOOL project. The evidence-based interventions focus on PA integrated into academic content (Move & Learn intervention) as embodied learning or PA as moderate to vigorous activity performed during the school day (Run, Jump & Fun intervention). The study’s objective was to engage teachers and pedagogues early in the design process to ensure the design was tailored to practice. Methods A team consisting of researchers, school staff, and experts were involved in the design process. The process lasted one school year and comprised three phases: exploration and analysis, construction and design, and reflection and evaluation. Multiple methods were used, including focus group interviews, a design workshop, and observations of iterative in-school testing. Results The result of the analysis and exploration phase was a set of learning points based on information about school culture, school staff competences, and needs. The design and construction phase produced a set of intervention skeletons, which were the actual elements of the interventions. The evaluation and reflection phase created the main results, which are specific principles and multifaceted implementation strategies for Move & Learn and Run, Jump & Fun, respectively. Finally, dose and timing of the interventions were specified. Conclusion Collaboration with schools and an iterative approach were determinants for designing interventions appropriate to the Danish school context and school staff practice.

Purpose The primary aims of this study were to examine the effects of 9 weeks of aerobic training, comprising three 30-min sessions per week, on VO2max, inhibitory control, and plasma brain-derived neurotrophic factor (BDNF) levels among adolescents aged 16-19 years. Methods One hundred twenty-one untrained or recreationally active adolescents from a Danish high school were enrolled in the study, with 58 females (17.8 +/- 0.8 years) and 27 males (18.0 +/- 0.9 years) completing it. Participants were randomly divided into three groups performing aerobic training at either moderate-intensity (MIT: 60%-70% heart rate reserve [HRR]) or high-intensity (HIT: 80%-100% HRR) or a passive control group (CON) continuing their habitual lifestyle. Both the training groups exercised for 3x30 min per week for 9 weeks using a combination of cycling and running. Before and after the intervention period maximal oxygen uptake (VO2max) and the primary outcomes (inhibitory control measured by a modified flanker task, and resting plasma levels of BDNF) were evaluated. Results After the intervention period, the HIT group demonstrated a larger increase in VO2max compared to both the CON and MIT groups, while no significant effects were observed on inhibitory control or plasma BDNF levels in any training group. However, compared to the CON group, the HIT group exhibited a tendency for greater improvement in the flanker interference score (accuracy), attributable to enhanced accuracy on the incongruent stimuli from pre to post. Conclusion Aerobic training in adolescents increased cardiorespiratory fitness in an intensity-dependent manner, but no clear effects were observed on neither inhibitory control nor resting plasma BDNF levels. Clinical Trial Registration: NCT02075944.

Background: Developmental Coordination Disorder is a commonly occurring, but poorly recognised developmental condition characterised by difficulties with motor functions. Danish tests of children’s motor functioning, which are currently available, are outdated and only applicable up to the age of seven years old. New tools are needed to enable easy and efficient screening of motor difficulties experienced by children living in Denmark.Aims/Objectives: We aimed to translate and adapt the Developmental Coordination Disorder Questionnaire (DCDQ) into Danish.Materials and Methods: A team of translators prepared the Danish version of the DCDQ. In total, 36 parents completed the questionnaire. The children completed fine and gross motor coordination tasks. Concurrent validity was tested using Pearson correlation on the DCDQ and motor performance scores. Internal consistency was tested using Cronbach’s alpha.Results: The results show good concurrent validity (r=.311) and internal consistency (α=.80).Conclusions: The Danish version of the DCDQ is well suited for use with Danish-speaking parents.Significance: The tool will aid early assessment of motor difficulties in children of Danish-speaking parents. The Danish DCDQ can be used by educational, occupational and health professionals as well as researchers in national and international contexts.

Background Previous research has suggested that school-based physical activity (PA) interventions may have a positive impact on academic performance. However, existing literature on school-based interventions encompasses various forms of PA, spanning from vigorous intensity PA outside the academic classes to light intensity PA and movement integrated into academic learning tasks, and results on academic performance are inconclusive. ACTIVE SCHOOL will implement two different PA interventions for one school year and assess the effects on the pupils’ academic performance, with math performance as the primary outcome. Methods/design The ACTIVE SCHOOL project consists of two phases: 1) Development phase and 2) Randomized Controlled Trial (RCT). In phase one, two interventions were developed in collaboration with school staff. The two interventions were tested in an 8-weeks feasibility study. In phase two, a RCT-study with three arms will be conducted in 9-10-year-old children for one school year. The RCT-study will be carried out in two intervention rounds during the school years 2023/2024 and 2024/2025. Schools will be randomized to one of two interventions or control;1) Run, Jump & Fun intervention (4 × 30 min/week of moderate-to-vigorous physical activity; 2) Move & Learn intervention (4 × 30 min/week focusing on embodied learning in math and Danish lessons); or 3) a control condition, consisting of normal teaching practices. Outcome measures include academic performance, PA level, cognitive functions, cardiorespiratory fitness, anthropometry, well-being and school motivation (collected before, during and after the intervention period). A process evaluation will be conducted to assess implementation. Discussion The ACTIVE SCHOOL study will expand knowledge regarding the impact of PA on academic performance. The study will have the potential to significantly contribute to future research, as well as the scientific and educational debate on the best way to implement PA to support education and learning. Trial registration The study was registered on the 25th of October 2022 in ClinicalTrials.gov, NCT05602948.

PURPOSE: To evaluate the implementation outcomes of two different school-based physical activity (PA) interventions during an 8 weeks pilot study.The two interventions were developed through a one-year design process:1)Move & Learn (ML): PA implemented into the curriculum in Danish and Math and based on embodied learning theories2)Run, Jump & Fun (RJF): High intensity PA based on exercise and cognition theories METHODS: Participants were 29 3rd grade teachers from seven public primary schools.Both interventions consisted of 4x30 minutes of PA weekly. Strategies to impact teacher understanding, acceptability and feasibility included:-Course (6 hours in week 0)-Supervision session (3 hours in week 4)-Materials (posters, booklets and videos)Implementation was measured using the Usage Rating Profile-Intervention (URP-I), a validated, 29-item self-report electronic questionnaire covering six indicators of adoptability and implementation of interventions. Five out of six factors were included: 1) Acceptability, 2) Understanding, 3) Feasibility, 4) System Climate and 5) System Support. All items were scored from 1 = strongly disagree to 6 = strongly agree and average ratings were computed. The URP-I was measured before and after the intervention. Group interviews with teachers were conducted. An interview guide were applied and interviews were thematically analyzed. RESULTS: The results showed no significant decline in any of the implementation outcomes except for acceptability in RJF. In all interviews, the course and supervision sessions were mentioned as the most important intervention strategies. - Implementation of Active School interventions measured by Usage Rating Profile-Intervention (URP-I) Move & Learn intervention Run, Jump & Fun intervention Week 0 Week 8 Difference Week 0 Week 8 Difference (n = 12) (n = 12) (n = 11) (n = 11) Factor Mean (sd) Mean (sd) p-value Mean (sd) Mean (sd) p-value Acceptability 5.02 (0.77) 4.83 (0.75) 0.34 5.05 (0.53) 4.78 (0.53) 0.09 Understanding 5.06 (0.78) 5.31 (0.48) 0.11 5.24 (0.70) 5.18 (0.50) 0.81 Feasibility 4.28 (0.89) 4.22 (0.71) 0.82 4.22 (0.41) 4.11 (0.68) 0.68 System Climate 4.68 (0.90) 4.77 (0.65) 0.50 4.62 (0.47) 4.35 (0.52) 0.27 System support 3.25 (1.06) 3.11 (1.37) 0.80 3.55 (0.76) 3.70 (0.99) 0.58 Response scale for URP-I items ranges from 1 = Strongly Disagree to 6 = Strongly Agree. CONCLUSION: Both interventions scored high for acceptability and understanding at baseline and follow-up in surveys and interviews, indicating that the implementation was sustained throughout the 8 weeks period. The two interventions are therefore ready for the next project phase, a three-armed RCT investigating academic performance and health outcomes.

BACKGROUND:The number of children and adolescents with obesity has increased worldwide. Some studies have found an increase in the intake of n-3 long-chain polyunsaturated fatty acid (LCPUFA) to be beneficial for weight and obesity status. The objectives of this study were to examine if intake of trans-fatty acids (TFA) and n-3 LCPUFA at school start was associated with weight and body fat development in the following 3 and 7 years, and if substituting other fats for n-3 LCPUFA in regression models influenced weight and body fat development.METHODS:A total of 285 children (boys:130, girls:155) were included in this study. Weight, height and skinfold thickness (SF) of children were measured at age 6, 9 and 13 years by trained research personnel. Multivariate linear regression models were used to investigate the associations between n-3 LCPUFA or TFA intake and subsequent changes in body mass index (BMI) or SF. To investigate substitution effects, we constructed regression models including information on n-3 LCPUFA and all other energy given components of the diet, except for the nutrient to be substituted (all other fats and specific subgroups; saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and other polyunsaturated fatty acids (PUFAs)).RESULTS:No significant associations were observed between intake of TFA or n-3 LCPUFA and changes in BMI and SF. Also, results from regression analysis showed substituting other fats for n-3 LCPUFA did not associate with BMI or SF development.CONCLUSION:The lack of associations between n-3 LCPUFA and TFA and adiposity suggests that fat composition in the diet does not play a major role in obesity development among school-aged children.

There is a rise in overweight and obesity among children and adolescents with type 1 diabetes (T1D) in parallel with the rise in the metabolic syndrome (MetS) among children and adolescents. The aim of the study was to describe the prevalence and characteristics of MetS in children and adolescents with T1D compared to their healthy counterparts.

The diet of Danish children is often not in accordance with dietary guidelines. We aimed to evaluate changes in the intake of selected foods and beverages during a multi-component school-based physical activity intervention, and to investigate if changes were modified by socioeconomic status (SES). The study included 307 children (intervention group: 184; comparison group: 123) with information on dietary intake pre- and post-intervention as well as on SES. Linear regression models were conducted to assess the effect of the intervention on changes in dietary factors. Children from the intervention group increased their intake of whole-grain bread during the intervention (group means: 6.1 g/d (95% CI: 2.2 to 10.0) vs. 0.3 g/d (95% CI: −3.1 to 3.7) in the comparison group, p = 0.04). A significant interaction between SES and group allocation was observed to change in fruit intake (p = 0.01). Among children from low SES families, only those from the comparison group decreased their fruit intake (group means: −40.0 g/d (95% CI: −56.0 to −23.9) vs. 9.3 g/d (95% CI: −16.1 to 94) in the intervention group, p = 0.006). The present study found no convincing effect of introducing a multi-component intervention on dietary intake except a small beneficial effect on whole-grain bread consumption. However, beneficial intervention effects in fruit intake were found particularly among children from low SES families.

It remains unclear whether the provision of additional physical activity in school improves academic outcomes. We conducted a secondary analysis of the Childhood Health, Activity, and Motor Performance School Study Denmark (CHAMPS-study DK), a natural experiment based on a trebling of curricular physical education, to investigate whether children receiving additional physical education performed better on their academic exams at the conclusion of compulsory education (i.e., 9th grade). Children from six intervention schools received 3–7 years of exposure to 270 weekly minutes of physical education (sports schools), while children from four control schools received the 90-min national standard (normal schools). Academic performance was based on the standard Danish 7-point scale (ranging from −03 to 12) and retrieved from national registries. The primary outcome was calculated as the average exam grade. Comparisons of participants at sports and normal schools were adjusted for individual socioeconomic factors and school-level academic environment. There were no differences in the pooled exam performance among 691 sports- and 510 normal-school participants (0.20 (95% confidence interval: −0.12 to 0.52)). Results for subject-specific exams indicated similar results. This analysis from a non-randomized natural experiment did not provide evidence that simply adding additional physical education is sufficient to affect academic performance relative to the national standard.

Objectives To determine if subpopulations of students benefit equally from school-based physical activity interventions in terms of cardiorespiratory fitness and physical activity. To examine if physical activity intensity mediates improvements in cardiorespiratory fitness. Design Pooled analysis of individual participant data from controlled trials that assessed the impact of school-based physical activity interventions on cardiorespiratory fitness and device-measured physical activity. Participants Data for 6621 children and adolescents aged 4–18 years from 20 trials were included. Main outcome measures Peak oxygen consumption (VO 2Peak mL/kg/min) and minutes of moderate and vigorous physical activity. Results Interventions modestly improved students’ cardiorespiratory fitness by 0.47 mL/kg/min (95% CI 0.33 to 0.61), but the effects were not distributed equally across subpopulations. Girls and older students benefited less than boys and younger students, respectively. Students with lower levels of initial fitness, and those with higher levels of baseline physical activity benefitted more than those who were initially fitter and less active, respectively. Interventions had a modest positive effect on physical activity with approximately one additional minute per day of both moderate and vigorous physical activity. Changes in vigorous, but not moderate intensity, physical activity explained a small amount (~5%) of the intervention effect on cardiorespiratory fitness. Conclusions Future interventions should include targeted strategies to address the needs of girls and older students. Interventions may also be improved by promoting more vigorous intensity physical activity. Interventions could mitigate declining youth cardiorespiratory fitness, increase physical activity and promote cardiovascular health if they can be delivered equitably and their effects sustained at the population level.

Background Adolescents’ health-related behavior varies from weekday to weekend. Only few studies, however, have examined to which degree such variation will affect markers of cardiometabolic health. Therefore, the primary aim of this study is to examine if markers of cardiometabolic health differ between different days of the week in adolescents. Methods This cross-sectional school-based study included up to 581 participants, 11–17 years old. Markers of metabolic health were insulin, glucose, triglyceride, HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C) and blood pressure. Linear mixed regression modelling was used to examine the cardiometabolic profile across weekdays. Results Significant declining trends were observed across the week in adolescents’ levels of cardiometabolic health markers. Lower levels of insulin (16.1%), glucose (2.6%) and triglyceride (24.7%) were observed on Fridays compared to Mondays ( p ≤ 0.006). Gradual improvement in measurement profiles across weekdays was less apparent for HDL-C, LDL-C, systolic blood pressure and diastolic blood pressure ( P ≥ 0.06). Analyses stratified by sex suggested a more noticeable pattern of gradual improvement across weekdays in boys than in girls. Conclusion Significantly lower levels of insulin, glucose and triglyceride were observed in adolescents on Fridays compared to Mondays. However, when sex specific analyses were performed significant profile variations were only observed across the week in boys. More research is needed to better understand which behavioral factors in particular seem to influence weekly variation in markers of cardiometabolic health - especially since such variation potentially will have an impact on how assessments of markers of cardiometabolic health optimally should be planned, standardized and carried out, both in research and in medical practice.

We analyzed the longitudinal association between dynamic balance and throwing skill with academic performance and whether waist circumference mediated these relationships. The current one-year longitudinal study followed 1020 first (mean age 7.87 ± 0.34 years) through fifth grade (mean age 11.87 ± 0.37 years) children, measured twice in 2010 and 2011. Dynamic balance and precision throw were measures of motor competence. Waist circumference was measured with a measuring tape at the umbilicus level. Academic performance was assessed by a combined score of standardized Danish language and math tests. Structural equation modeling was used for analysis. All coefficients are standardized. Balance was associated with academic performance when both sexes were combined (β = 0.126, 95% CI: 0.074 to 0.179), and waist circumference partially mediated the relationship (β = 0.021, 95% CI: 0.008 to 0.034). For boys, balance was associated with academic performance, but waist circumference did not mediate the association. For girls, balance presented direct, mediated (via waist circumference), and total associations with academic performance. Dynamic balance is an important gross motor function that was longitudinally related to academic performance, and waist circumference partially mediated the relationship. Precision throw was not found to be associated with academic performance in both sexes combined or when analyzed separately.

It is not known how effective specific types of motor-enriched activities are at improving academic learning and early reading skills in children. The aim of this study was to investigate whether fine or gross motor enrichment during a single session of recognizing letters “b”/“d” can improve within-session performance or delayed retention the following day in comparison to letter recognition practice without movement. Furthermore, the aim was to investigate children’s motivation to perform the specific tasks. We used a randomized controlled intervention study-design to investigate the effect of 10-min motor-enriched “b”/“d” letter training on children’s ability to recognize the letters “b” and “d” (n = 127, mean age = 7.61 ± SD = 0.44 years) acutely, and in a delayed retention test. Three groups were included: a fine motor-enriched group (FME), a gross motor-enriched group (GME), that received 10 min of “b” and “d” training with enriched gestures (fine or gross motor movements, respectively), and a control group (CON), which received non motor-enriched “b”/“d” training. The children’s ability to recognize “b” and “d” were tested before (T0), immediately after (T1), and one day after the intervention (T2) using a “b”/“d” Recognition Test. Based on a generalized linear mixed model a significant group-time interaction was found for accuracy in the “b”/“d” Recognition Test. Specifically, FME improved their ability to recognize “b”/“d” at post intervention (T0→T1, p = 0.008) and one-day retention test (T0→T2, p < 0.001) more than CON. There was no significant difference in change between GME and CON. For reaction time there were no significant global interaction effects observed. However, planned post hoc comparisons revealed a significant difference between GME and CON immediately after the intervention (T0→T1, p = 0.03). The children’s motivation-score was higher for FME and GME compared to CON (FME-CON: p = 0.01; GME-CON: p = 0.01). The study demonstrated that fine motor-enriched training improved children’s letter recognition more than non motor activities. Both types of motor training were accompanied by higher intrinsic motivation for the children compared to the non motor training group. The study suggests a new method for motor-enriched letter learning and future research should investigate the underlying mechanisms.

Objectives: To examine longitudinal (seven years) relationships among cardiorespiratory fitness (VO2peak), body fatness, and motor competence. Method: Data were collected as part of the Copenhagen School Child Intervention Study (CoSCIS). Body fatness was assessed by the sum of four skinfolds. VO2peak was measured directly in a continuous running protocol. Motor competence was assessed using the Korperkoordinationtest fur Kinder. This study used multilevel linear mixed models to evaluate the reciprocal longitudinal association between body fatness, VO2peak, and motor competence. All regressions were stratified by sex and adjusted by intervention and pubertal status. All variable coefficients were standardized. Results: A reciprocal relationship was observed between children's motor competence with body fatness and VO2peak at the seven-year follow-up (6-13 years of age). Children with higher motor competence at baseline had a lower risk of having higher body fatness (beta(boys) = -0.45, 95% CI: -0.52 to -0.38; beta(girls) = -0.35, 95% CI: -0.42 to -0.28) and higher VO2peak (beta(boys) = 0.34, 95% CI: 0.27-0.40; beta(girls) =0.27, 95% CI: 0.20-0.33) during childhood. Alternatively, higher body fatness or lower levels of VO2peak at baseline were associated with lower motor competence during childhood. Conclusions: These data suggest motor competence, body fatness, and VO2peak demonstrate reciprocal relationships across childhood (6-13 years of age). Interventions addressing motor competence, cardiorespiratory fitness, and body fatness in early childhood are recommended, as intervention effects are likely to be enhanced because of the mutual reciprocal associations between these three variables. (C) 2019 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda.

Abstract Background Evidence on the association between sitting for extended periods (i.e. prolonged sedentary time (PST)) and cardio-metabolic health is inconsistent in children. We aimed to estimate the differences in cardio-metabolic health associated with substituting PST with non-prolonged sedentary time (non-PST), light (LIPA) or moderate-to-vigorous physical activity (MVPA) in children. Methods Cross-sectional data from 14 studies (7 countries) in the International Children’s Accelerometry Database (ICAD, 1998–2009) was included. Accelerometry in 19,502 participants aged 3–18 years, together with covariate and outcome data, was pooled and harmonized. Iso-temporal substitution in linear regression models provided beta coefficients (95%CI) for substitution of 1 h/day PST (sedentary time accumulated in bouts > 15 min) with non-PST, LIPA or MVPA, for each study, which were meta-analysed. Results Modelling substitution of 1 h/day of PST with non-PST suggested reductions in standardized BMI, but estimates were > 7-fold greater for substitution with MVPA (− 0.44 (− 0.62; − 0.26) SD units). Only reallocation by MVPA was beneficial for waist circumference (− 3.07 (− 4.47; − 1.68) cm), systolic blood pressure (− 1.53 (− 2.42; − 0.65) mmHg) and clustered cardio-metabolic risk (− 0.18 (− 0.3; − 0.1) SD units). For HDL-cholesterol and diastolic blood pressure, substitution with LIPA was beneficial; however, substitution with MVPA showed 5-fold stronger effect estimates (HDL-cholesterol: 0.05 (0.01; 0.10) mmol/l); diastolic blood pressure: − 0.81 (− 1.38; − 0.24) mmHg). Conclusions Replacement of PST with MVPA may be the preferred scenario for behaviour change, given beneficial associations with a wide range of cardio-metabolic risk factors (including adiposity, HDL-cholesterol, blood pressure and clustered cardio-metabolic risk). Effect estimates are clinically relevant (e.g. an estimated reduction in waist circumference of ≈1.5 cm for 30 min/day replacement). Replacement with LIPA could be beneficial for some of these risk factors, however with substantially lower effect estimates.

BACKGROUNDTo analyze the longitudinal association between academic performance and moderate to vigorous physical activity (MVPA), vigorous physical activity (VPA), and sedentary (SED) in a 3-year longitudinal study. A secondary aim was to determine whether MVPA and VPA were indirectly related with academic performance via waist circumference (WC).METHODSPhysical activity (PA) and SED were measured by accelerometers. Academic performance was assessed by national tests in Danish and Math. Structural equation modeling was performed to evaluate whether MVPA, VPA, and SED were associated with academic performance and the potential PA-academic performance indirect relationship via WC.RESULTSMVPA and VPA were associated with academic performance, mediated via WC (β = 0.036; 95% confidence interval [CI], 0.002 to 0.070 and β = 0.096; 95% CI, 0.027 to 0.164, respectively). SED was directly associated with academic performance (β = 0.124; 95% CI, 0.030 to 0.217, MVPA model and β = 0.132; 95% CI, 0.044 to 0.221, VPA model). WC was negatively associated with academic performance.CONCLUSIONSBoth PA and SED time were positively associated with academic performance. Based on this, PA should be encouraged in children and youth not only to promote physical health but also to promote academic performance. Future studies should distinguish between school-related SED and other SED activities and their relationship with academic performance.