The 24-h movement behaviours composition is associated with parasympathetic modulation in preschoolers.

AIM: To investigate the associations between 24-h movement behaviours and heart rate variability (HRV) in preschool children. METHODS: A total of 123 preschoolers (4.52 ± 0.25 years old; 62 girls) were assessed for physical activity (PA) and sedentary behaviour (SB) using an accelerometer (Actigraph WGT3x). Sleep duration (SD) was parent-reported. Children were laid down in a supine position for 10 min to assess HRV data. The R-R intervals recorded during the last 5 min of this period were analysed. We conducted compositional analysis in R studio, and the significance level was 95%. All ethical procedures were followed, and the study had the approval of the local ethical board. RESULTS: When considered as a composition, adjusted for age, body mass index and sex, the 24-h movement composition (PA, SB and SD) significantly predicted better parasympathetic modulation (Root mean square of the successive differences [RMSSD] [p = 0.04; r2 = 0.13]), but not high frequency (HF) (nu) (p = 0.51, r2 = 0.01), low frequency (nu) (p = 0.52, r2 = 0.02),or standard deviation (standard deviation of normal-to-normal intervals) (p = 0.55, r2 = 0.02), respectively. CONCLUSION: These results suggest the 24-h movement composition predicted the RMSSD time-domain index related to parasympathetic activity.

Sex differences in 3- to 5-year-old children's motor competence: A pooled cross-sectional analysis of 6241 children.

There is some, albeit inconsistent, evidence supporting sex differences in preschoolers' motor competence (MC), with these observations not uniform when analyzed by age, and cultural groups. Thus, this study examined sex differences across ages in 3- to 5-year-old children's MC. A cross-country pooled sample of 6241 children aged 3-5 years (49.6% girls) was assessed for MC using the Test of Gross Motor Development-2nd/3rd edition, and children were categorized into groups of age in months. Multiple linear regression models and predictive margins were calculated to explore how sex and age in months affect scores of MC (i.e., locomotor and ball skills), with adjustments for country and BMI. The Chow's Test was used to test for the presence of a structural break in the data. Significant differences in favor of girls were seen at 57-59 and 66-68 months of age for locomotor skills; boys performed better in ball skills in all age periods, except for 42-44 and 45-47 months of age. The higher marginal effects were observed for the period between 45-47 and 48-50 months for locomotor skills (F = 30.21; and F = 25.90 for girls and boys, respectively), and ball skills (F = 19.01; and F = 42.11 for girls and boys, respectively). A significantly positive break point was seen at 45-47 months, highlighting the age interval where children's MC drastically improved. The identification of this breakpoint provides an evidence-based metric for when we might expect MC to rapidly increase, and an indicator of early delay when change does not occur at that age.

WEB OF TRANSFORMATIONS: impact of multicomponent intervention on the relationship between sociodemographic indicators, changes in body composition, cardiorespiratory fitness and biochemical markers in adolescents with overweight and obesity.

The study aims to analyze the relationships between changes after multicomponent intervention in sociodemographic indicators, body composition, cardiorespiratory fitness and biochemical markers in overweight/obese adolescents. Quasi-experimental study with 33 overweight/obese adolescents (17 in the intervention group (IG) and 16 in the control group (16)), in which the GI participated in the multicomponent intervention for 24 weeks. Sociodemographic indicators, body composition, cardiorespiratory fitness and biochemical markers were evaluated. Network analysis was performed using JASP software. In GI, the reduction in %BF proved to be the variable with greater connectivity and strength in the network compared to the control network. Changes in %BF were related to changes in ACR, BMI and leptin. It is concluded that the reduction in %BF is the most important variable in network relationships after the intervention, suggesting that the greater the reduction in %BF, the greater the effect on variables such as BMI, ACR and leptina.

Are low-income preschoolers physically active at preschool settings? A cross-sectional study.

BACKGROUND: Preschools may provide opportunities for children to engage in physical activity (PA), to benefit their health, although little is known when concerning low-income preschoolers. This study aimed (1) to describe time spent in PA among low-income children during preschool hours and (2) to analyse how many children meet the PA recommendations during preschool hours. METHODS: A total of 204 low-income preschoolers (4.51 ± 0.79 years) from João Pessoa/Brazil provided valid accelerometer (Actigraph, WGT3-X) data during the preschool period. Children were grouped in quartiles of PA in counts per minute, according to sex and age. The General Linear Model Univariate was used to examine the differences in PA intensities between the quartiles and the time spent in total PA (TPA) and moderate-to-vigorous PA (MVPA) by quartiles, according to age. An hour-by-hour description of children's PA was presented. RESULTS: TPA during preschool hours ranged from 68.33% to 113.89% of the recommended and from 28.34% to 81.68% of the MVPA recommendations. Among 5-year-old children, those in the highest quartile met the PA recommendations. All children were more active outdoors than indoors. For the less actives, preschool time corresponded to 30% of the recommended daily MVPA. CONCLUSION: The current results reinforce the importance of preschool settings for promoting preschoolers' PA and provide particularly important and useful information for tailoring preschool-based interventions focused on those who need it most. Strategies to increase children's MVPA should be prioritized during free-play time.

Effects of a physical education intervention on children's physical activity and fitness: the PROFIT pilot study.

BACKGROUND: Physical education classes are widely accepted as one of the most effective settings for promoting physical activity and health and have often been used to implement physical activity interventions. The aim of this pilot study was to test a physical education intervention program on physical activity levels and physical fitness in a sample of school-age children. METHODS: Participants were a convenience sample of 50 children (34 experimental group and 16 in the comparative group) aged between 6 and 11 years old (Mean = 8.28 years). A 21-week intervention was implemented, consisting of high-intensity and physical fitness-focused exercises, in addition to a once-a-month extra class nutritional education. The following variables were evaluated before and post-intervention: physical fitness, sedentary behavior (SB), light physical activity (LPA), moderate physical activity (MVA), and vigorous physical activity (VPA). Propensity score analyses calculated the average treatment effect on the treated (ATET) within a quasi-experimental framework. RESULTS: Physical fitness variables showed improvements after the intervention, specifically for agility (ATET = -0.67 s; p < 0.001), cardiorespiratory fitness (ATET = 89.27 m; p = 0.045), lower limbs power (ATET = 4.47 centimeters; p = 0.025), and speed (ATET = -1.06 s; p < 0.001). For physical activity and SB levels, there were no improvements after intervention implementation. CONCLUSION: The intervention program showed preliminary effectiveness to improve physical fitness of children, but not SB nor physical activity.

Are there associations between sedentary time inside and outside preschools with preschoolers' executive function?

Preschool children spend a large part of their day at school, and a large part of that time they spend in sedentary time. Although sedentary time negatively affects regions of the brain responsible for cognition, it is believed that the type of sedentary time performed can favor executive functions' performance. The present study explored the associations between sedentary time inside and outside preschools with executive function (EF) tasks in preschoolers. Seventy-three preschool children (60% girls; 55.0 ± 9.1 months of age) were objectively assessed for sedentary time and physical activity (PA) using accelerometers (wGT3X). EF was evaluated using the Go/No-Go paradigm through the Early Years Toolbox - YET. Go's inverse efficiency (IE) and the No-Go accuracy were analyzed. To establish possible associations between EF and sedentary time, a structural equation model was conducted after adjustments for sex, age, body mass index, and moderate-to-vigorous PA. A significant and positive association between sedentary time on weekend days and IE (b = 0.61; p < .001) was observed. The general model explained 52% of the variation in IE and 2.1% in the accuracy of No-Go. The sedentary time on weekend days seems to be related to worse EI. This result emphasizes a context-dependent association between time being sedentary and preschoolers' EF. Further investigations should focus on exploring the type of sedentary behavior children are engaged in different contexts.

Compliance with the 24-h movement behaviors guidelines among urban and rural Brazilian preschoolers.

BACKGROUND: The importance of movement behaviors for health is well-known, although few studies have examined the compliance with movement guidelines in preschoolers from different living contexts. This study reported the compliance with the 24-h movement behaviors guidelines among low-income Brazilian preschoolers from rural and urban areas, according to age. METHODS: A total of 453 preschoolers (n = 222 urban), aged between 3 and 5 years, provided physical activity (PA) data (Actigraph wGT3X). Sleep duration, and screen time were parent-reported. Preschoolers were classified as compliant/non- compliant with the 24-h movement guidelines, according to age. The association between prevalence of compliance with the recommendations and the children's living setting were estimated (SPSS; 27.0). RESULTS: Preschoolers were active (mean = 299.19 ± 76.42; and 369.76 ± 95.56 min/day in urban and rural areas, respectively), though moderate-to-vigorous physical activity (MVPA) time was below the 60 daily minutes recommended in both urban and rural settings (mean = 38.39 ± 21.36; and 47.32 ± 24.28, respectively). None of the urban children complied with the three recommendations simultaneously, while in the rural area, only 2.6% were compliant. Single movement behaviors compliances in the urban setting were 6.8%, 28.8% and 5.4% for PA, sleep, and screen time, respectively; while for rural settings were 16.5%, 21.2%, and 7.4%. Living in the rural area was related to the compliance with PA recommendation for the 5-year-old preschoolers. CONCLUSION: In both urban and rural Brazilian areas, very few preschoolers are compliant with the guidelines, and more than one third of the children do not comply with any of the recommendations. Strategies and programs to promote compliance with movement behaviors guidelines should consider children's living setting and their age groups.

Motor Competence and Body Mass Index in the Preschool Years: A Pooled Cross-Sectional Analysis of 5545 Children from Eight Countries.

BACKGROUND AND OBJECTIVE: One in five preschool children are overweight/obese, and increased weight status over time increases the risks of poorer future health. Motor skill competence may be a protective factor, giving children the ability to participate in health-enhancing physical activity. Yet, we do not know when the relationship between motor competence and weight status first emerges or whether it is evident across the body mass index (BMI) spectrum. This study examined the association between motor skill competence and BMI in a multi-country sample of 5545 preschoolers (54.36 ± 9.15 months of age; 50.5% boys) from eight countries. METHODS: Quantile regression analyses were used to explore the associations between motor skill competence (assessed using the Test of Gross Motor Development, Second/Third Edition) and quantiles of BMI (15th; 50th; 85th; and 97th percentiles), adjusted for sex, age in months, and country. RESULTS: Negative associations of locomotor skills, ball skills, and overall motor skill competence with BMI percentiles (p < 0.005) were seen, which became stronger at the higher end of the BMI distribution (97th percentile). Regardless of sex, for each raw score point increase in locomotor skills, ball skills, and overall motor skill competence scores, BMI is reduced by 8.9%, 6.8%, and 5.1%, respectively, for those preschoolers at the 97th BMI percentile onwards. CONCLUSIONS: Public health policies should position motor skill competence as critical for children's obesity prevention from early childhood onwards. Robust longitudinal and experimental designs are encouraged to explore a possible causal pathway between motor skill competence and BMI from early childhood.

Replacing screen time, with physical activity and sleep time: influence on cardiovascular indicators and inflammatory markers in Brazilian children.

OBJECTIVE: To examine if the substitution of different screen time intervals with light physical activity (LPA), moderate to vigorous physical activity (MVPA) and sleep is associated with cardiovascular indicators and inflammatory markers in children. METHODS: This is a cross-sectional study developed with 186 children aged between six and 11 years old from public schools in southern Brazil. CRF was measured with the 6-minute running and walking test, following the Brazil Sports Project procedures. The percentage of fat was evaluated through DXA. LPA and MVPA were measured using accelerometers. Sleep and screen time were assessed by questionnaires answered by parents. Leptin and C-reactive protein were measured by fasting blood collection. Systolic and diastolic blood pressure were determined through a digital sphygmomanometer. Isotemporal substitution models were used for statistical analysis. RESULTS: Replacing 1 h of screen time with MVPA was associated with lower BMI, systolic and diastolic blood pressure, fat percentage, leptin, and C-reactive protein. When screen time was substituted for sleep time, lower waist circumference was observed. Regarding the substitution of 1 h of screen time with LPA, significant values were found only for leptin. CONCLUSION: The replacement of screen time with physical activities of different intensities and sleep time was associated with benefits in cardiovascular indicators and inflammatory markers in childhood.

Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week: An analysis with 707,616 adolescents.

BACKGROUND: Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity (MVPA). However, using only this cut-off could hide important information. For instance, from a population-level point of view, increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate levels. Also, including a more sensitive cut-point of ≥1 day per week could be an additional strategy for identifying those with low access/opportunities for physical activity practice. Thus, the current study aims to estimate the prevalence of ≥60 min of MVPA ≥1 days per week among adolescents globally, and to describe any relevant gender inequalities. METHODS: We used representative datasets from 146 countries/territories collected between 2003 and 2019. MVPA was self-reported. Participants were grouped into younger (≤14 years old) and older (>14 years old) adolescents. Crude Poisson regression models were used to identify the relative differences in ≥60 min of MVPA ≥1 days per week between boys and girls, and random-effects meta-analysis models were used to identify the pooled estimates. Analyses were stratified by country and region. RESULTS: Approximately 80% of both younger and older adolescents reported ≥60 min of MVPA ≥1 days per week. This prevalence was ≥94% in Europe and Central Asia and North America, while the estimates for the other regions were <77%. The prevalence of ≥60 min of MVPA ≥1 days per week was higher among boys than girls, with the largest differences occurring among the oldest adolescents (PR≤14y: 1.04 (95% confidence interval (95%CI): 1.03‒1.04) vs. PR>14y: 1.09 (95%CI: 1.08‒1.10)). CONCLUSION: Approximately 8 out of 10 adolescents reported accumulating ≥60 min of MVPA ≥1 day per week, with notable differences between regions. Gender differences were observed in several countries, especially among the oldest adolescents. Priorities for physical activity promotion among adolescents should include increasing access/opportunities for physical activity among those who do not achieve ≥60 min of MVPA ≥1 days per week and reducing gender inequalities.

Paths towards a healthier BMI among short and adequate sleepers: A pathway network analysis considering movement behaviors in low-income preschoolers.

INTRODUCTION: Short sleep duration has been seen as a predictor of higher body mass index (BMI) in youth. Sleep duration varies substantially along early childhood, and the paths towards a healthier BMI, considering the other movement behaviors (physical activity-PA and screen time) are unexplored in preschoolers. AIM: To construct a sleep-BMI model to capture the direct and indirect paths to intervening towards a healthier BMI, according to low-income preschoolers' compliance with the other movement behaviors. METHODS: Two hundred and seventy two preschoolers (4.5 ± 0.0; 138 boys) participated in the study. Sleep and screen time (ST) were assessed in a face-to-face interview with primary caregivers. PA was assessed using accelerometer (wGT3X-BT). Preschoolers were categorized as compliant or not with sleep, screen time, total and moderate to vigorous PA recommendations. BMIz-score was calculated according to preschoolers' sex and age. All the assessed variables, besides sex and age were included in a Network Pathway Analysis (NPA) according to age as nodes. RESULTS: At 3 years old, a direct and negative path between sleep-BMIz score was observed. At four and 5 years old, this relationship became positive. Further, girls were more compliant with sleep, ST and total PA recommendations. Total PA (TPA) showed the highest expected influence value in the general, 3 and 4 years old NPA. CONCLUSION: The NPA analysis showed different directions for the relationship between sleep and BMIz score, according to age. Intervention strategies to a healthier BMI among preschoolers compliant or not with sleep recommendations should focus in increasing TPA.

A Novel Exploratory Graph-Based Analytical Tool for Functional Near-Infrared Spectroscopy in Naturalistic Experiments: An Illustrative Application in Typically Developing Children.

Naturalistic paradigms are being increasingly applied to investigate human brain function. Compared with resting-state and task-based paradigms in neuroimaging, naturalistic stimuli and situations can be potentially more readily translated to daily-life applications. Among neuroimaging modalities, functional near-infrared spectroscopy (fNIRS) is particularly suitable for naturalistic investigations and applications. However, specific and tailored statistical analysis to interrogate brain function using naturalistic fNIRS is warranted. Here, we describe an exploratory graph-centrality-based approach to investigating participants' spatiotemporal similarities from the fNIRS signal. We illustrate the usefulness of our approach in a sample of typically developing children (10 males and 9 females; mean age of 5.2 years old; sd = 0.78) while they watch the Inscapes movie designed for neuroimaging acquisition. A node in the left dorsal prefrontal cortex presented similar responses across children, and those fNIRS responses were in line with scene transitions in the movie stimulus. Our results suggest the feasibility of applying centrality graph-based measures to investigate brain function in naturalistic fNIRS during development.

Crucial workload variables in female-male elite Brazilian Beach Handball: An exploratory factor analysis.

This study aimed to identify the most important variables of male and female beach handball workload demands and compare them by sex. A total of 92 elite Brazilian beach handball players (54 male: age 22.1 ± 2.6 years, height 1.8 ± 0.5 m, weight 77.6 ± 13.4 kg; and 38 female: age 24.4 ± 5.5 years, height 1.7 ± 0.5 m, weight 67.5 ± 6.5 kg) were analyzed in 24 official matches during a four-day congested tournament. From 250 variables measured by the inertial measurement unit, fourteen were extracted for analysis using Principal Component Analysis as selection criteria. Five Principal Components (PC) were extracted that explained 81.2-82.8% of total variance (overview of workload demands during beach handball). Specifically, 36.2-39.3% was explained by PC1 (DistanceExpl, Distance, Distance4-7 km/h, and Acc), 15-18% by PC2 (AccMax, Acc3-4 m/s, Dec4-3 m/s), 10.7-12.9% by PC3 (JumpsAvg Take-Off, JumpsAvg Landing and PLRT), 8-9.4% by PC4 (Distance> 18.1 km/h, SpeedMax), and 6.7-7.7% by PC5 (HRAvg and Step Balance). Sex-related differences were found in the PC distribution of variables, as well as in selected variables (HRAvg, Dec4-3 m/s, Acc3-4 m/s, JumpsAvg Take-Off, JumpsAvg Landing, AccMax, Distance, Distance4-7 km/h, Acc, SpeedMax) with higher values in male players (p < .05). In conclusion, the sex-related PC distribution and workload demands in beach handball should consider for training design and injury prevention programs.

The relative age effect on fundamental movement skillsl in Chinese children aged 3-5 years.

BACKGROUND: The cut-off date in the education system causes a relative age difference, with developmental advantages for children who are born on the "early side" of the cut-off date and disadvantages for those born later, which is known as the relative age effect (RAE). Very few studies have examined whether there is a RAE on the development of fundamental movement skills (FMSs) in preschool children, and no studies have been conducted in China. The purpose of this study is to identify whether a RAE exists on FMS in Chinese preschool children, comparing RAEs according to gender and age. METHODS: From a total of 378 invited preschool children regularly registered at one Chinese kindergarten, a total of 288 healthy and typically developing preschoolers (4.33 ± 0.84 years-old; 56.6% boys) were included in this study. All children were required to take part in anthropometry and FMS assessments. Analysis of covariance (ANCOVA) was applied to examine the difference in each of the FMS items across quarter categories, year and gender groups, controlling for body mass index (BMI). RESULTS: For the overall sample, the data show the significant main effects on the quarter of birth factor in locomotor skills (LC; F (3, 265) = 2.811, p = 0.04, ηp2 = 0.031), object control skills (OB; F (3, 265) = 6.319, p = 0.04, ηp2 = 0.031), and total test score (TTS; F (3, 265) = 5.988, p = 0.001, ηp2 = 0.063). There were also significant differences in the age effect on all the domains of FMS (FLC (2, 265) = 100.654, p < 0.001, ηp2 = 0.432; FOB (2, 265) = 108.430, p < 0.001, ηp2 = 0.450; FTTS (2, 265) = 147.234, p < 0.001, ηp2 = 0.526) but a gender effect only in LC (F (1, 265) = 20.858; p < 0.001; ηp2 = 0.073). For gender and quarter of birth groups, RAEs in LC only exists in girls. Moreover, regarding age and quarter of birth factors, RAEs are only found at younger ages. CONCLUSIONS: This study suggests the existence of RAEs in the FMS of Chinese preschool children. Teachers need to be aware of the effect of RAEs on the FMS when approaching development, evaluation, and teaching approaches in preschools.

Prevalence and Sociodemographic Correlates of Meeting the 24-Hour Movement Guidelines Among Low-Income Brazilian Older Adults With Chronic Diseases.

This study examined the prevalence and sociodemographic correlates of meeting individual behavior and 24-hr movement behavior guidelines among Brazilian older adults with chronic diseases. The sample comprised 273 older adults aged ≥60 years (80.2% women) with chronic diseases from Recife, Pernambuco, Brazil. Sociodemographic variables were self-reported, while 24-hr movement behaviors were assessed by accelerometry. Participants were classified as meeting (or not meeting) individual and integrated recommendations for moderate-to-vigorous physical activity (MVPA), sedentary behavior, and sleep duration. No participant met the 24-hr movement behavior guidelines, while only 8.4% met integrated MVPA/sleep recommendations. The prevalence of meeting recommendations of MVPA, sedentary behavior, and sleep was 28.9%, 0.4%, and 32.6%, respectively. Discrepancies according to sociodemographic variables on meeting MVPA recommendations existed. The findings show the need for dissemination and implementation strategies to foster adoption of the 24-hr movement behavior guidelines among Brazilian older adults with chronic diseases.

Association between the physical activity environment in schools and childhood obesity: a view under the light of complex systems

Objective: to analyse the relationship between physical activity (PA) environment at schools and obesity in children, the light of complex systems. Methods: this is a cross sectional study involved 1.200 children (8.1 ± 1.0 years old and 50% boys) from eight public schools from socially vulnerable neighbourhoods of Petrolina, Brazil. Weight and height measurements were assessed to calculate the Body Mass Index (BMI) and classified as normal weight and overweight. To assess the PA environment at the school, a questionnaire about the structural and organizational environment of the school was applied through a face-to-face interview with the school´s manager was conducted. The association between the PA environment at school and obesity was tested using a Machine Learning technique (Network Analysis) performed on the Jasp software. Results: positive associations between BMI and Physical Education classes (0.847), physical education teacher (0.349), break duration (0.564) and indoor sports court (0.662) were observed. Negative associations were seen with sex (-0.212) age (- 0.387), extracurricular PA (-0.492) and playground (-0.557). Additionally, the centrality indicators highlighted extracurricular PA (1.789) as the variables with the highest betweenness values, and BMI with the highest closeness (2.239) and strength (1.230) values. Conclusion: Extracurricular PA and the presence of playgrounds at school´s environment are associated with a healthier weight status low-income children.

Fatores associados aos comportamentos ativo e sedentário em adolescentes brasileiros: uma análise de redes / Factors associated with active and sedentary behaviors in Brazilian adolescents: a network analysis

O presente estudo verificou a associação entre variáveis sociodemográficas, características da esco-la, nível de atividade física (AF) e comportamento sedentário (CS) em adolescentes brasileiros. A amostra foi composta por 71.903 adolescentes entre 13 e 16 anos (52,8% meninas), matriculados no último ano do ensino fundamental, em escolas públicas e privadas do Brasil, participantes da terceira edição da Pesquisa Nacional da Saúde do Escolar (PeNSE). As informações foram recolhidas através de questionário. O tempo de AF na aula de Educação Física e extra aula de Educação Física, o tempo em deslocamento ativo e o tempo em CS foram associados às variáveis sociodemográficas (tipo de município, local da escola, escolaridade da mãe, percepção de insegurança, idade e sexo) e características da escola (tipo de escola e quadra disponível para uso). Utilizou-se a análise de rede. Quanto ao comportamento ativo, a topologia de rede mostrou que os meninos são mais ativos do que as meninas, principalmente na AF extra aula de Educação Física. Além disso, os resultados revelaram um maior tempo de AF na aula de Educação Física para os meninos, estudantes cujas mães apresentavam maior escolaridade, matriculados em escolas privadas e com quadra disponível para uso. Os estudantes matriculados em escolas públicas apresentaram maior tempo de AF em deslocamento ativo. Quanto ao CS, jovens do contexto urbano apresentaram maior exposição quando comparados aos pares do contexto rural. Conclui-se que as características sociodemográficas e da escola estão relacionadas com os comportamentos dos adolescentes brasileiros em todos os domínios da AF e no CS

The present study aimed to verify the association of sociodemographic correlates and school characteristics with levels of physical activity (PA) and sedentary behavior (SB) of Brazilian adolescents. The sample consisted of 71,903 adolescents between 13 and 16 years old (52.8% girls), enrolled in the last year in public and pri-vate elementary schools of Brazil, participants of the third edition of the National Survey of School Health (PeNSE). The time of PA in Physical Education class and extra Physical Education class, time in active commuting and time in SB were related to sociodemographic variables (type of municipality, place where the school is located, mother's schooling, perception of insecurity, age and gender) and school characteristics (type of school, block available for use). Data were analyzed using network analysis. The network topology showed that boys are more active than girls, especially in extra Physical Education`s PA. In addition, boys, students whose mothers have higher education, enrolled in private schools, which have a court available for use, have a positive association with longer time spent in PA in physical education classes. Students enrolled in public schools had a positive association with time spent in active commuting PA. As for SB, young people from the urban context are more exposed to SB than rural context. It was concluded that sociodemographic correlates and characteristics of the school were associated with all domains of the physical activity and sedentary behavior

Investigating the Construct Validity and Reliability of the Test of Motor Competence Across Iranians' Lifespan.

Motor competence (MC) has been extensively examined in children and adolescents, but has not been studied among adults nor across the lifespan. The Test of Motor Competence (TMC) assesses MC in people aged 5-85 years. Among Iranians, aged 5-85 years, we aimed to determine the construct validity and reliability of the TMC and to examine associations between TMC test items and the participants' age, sex, and body mass index (BMI). We conducted confirmatory factor analysis (CFA) to evaluate the TMC's factorial structure by age group and for the whole sample. We explored associations between the TMC test items and participant age, sex, and BMI using a network analysis machine learning technique (Rstudio and qgraph). CFA supported the construct validity of a unidimensional model for motor competence for the whole sample (RMSEA = 0.003; CFI = 0.998; TLI = 0.993) and for three age groups (RMSEA <0.08; CFI and TLI >0.95). Network analyses showed fine motor skills to be the most critical centrality skills, reinforcing the importance of fine motor skills for performing and participating in many daily activities across the lifespan. We found the TMC to be a valid and reliable test to measure MC across Iranians' lifespan. We also demonstrated the advantages of using a machine learning approach via network analysis to evaluate associations between skills in a complex system.

Does parents' perception of the environment associates with outdoor physical activity duration in low-income preschoolers?

Parents' perception of the environment may influence the time spent in outdoor physical activities in pre-school children. This study aimed to analyze the association between parents' perception of the environment and outdoor physical activities outside the school in low-income preschoolers. In total, 129 preschoolers aged 3 to 5 years (4.4 years ± 0.7 years, 50% boys) and their parents participated in the study. An adapted version of the Neighborhood Environmental Walkability Scale was used to obtain parents' environmental perceptions. Outdoor physical activities was measured based on two questions considering the usual time spent in these activities during week and weekend days. Information on sociodemographic was collected by interview. Logistic regression was used to analyze the associations. Statistical analyses were conducted using SPSS, version 21.0. Most preschoolers (76.9%) had ≤ 2 hours/day in outdoor physical activities during the week while at the weekend, 65.9% reached > 2 hours. Parents' perception of unsafe traffic (OR = 0.39; p = 0.03) was associated with higher chances for a shorter time in outdoor physical activities both during the week and at the weekend (OR = 0.46; p = 0.04). Moreover, preschoolers' whose parents perceive a lack of places to walk (OR = 0.33; p = 0.02) and unsafe night time (OR = 0.36; p = 0.04) are more likely to spend less time in outdoor physical activities during the week. After adjustments for sociodemographic confounders, the perception of unsafe traffic (OR = 0.26; p = 0.01) and places to walk (OR = 0.15; p = 0.01) were predictors of preschooler's shorter time in outdoor physical activities during the week. Parents' perception of unsafe traffic and places to walk were associated with less time in outdoor physical activities in low-income preschoolers.