Biological maturation, fat mass and cardiorespiratory fitness in prepubescent girls: A mediation analysis.

BACKGROUND: The association between indicators of maturation and measures of physical fitness are not well correlated and vary according to chronological age, sex, body size, and motor characteristics. It is known that chronological age, maturation, and fat mass are significant predictors of cardiorespiratory fitness in girls, however, the contributions of fat mass to the relationship between maturation and endurance performance are still unclear. OBJECTIVE: The current study aimed to examine whether the association between somatic maturation and running performance in the 20-m shuttle-run in girls is mediated by estimated fat mass. METHODS: The sample comprised 67 girls, aged 8.00-8.99 years. Stature, body mass, and skinfolds were measured. Estimates of body composition and predicted mature stature (PMS) were then calculated. Current stature was expressed as a percentage of PMS and somatic maturation was given by z-scores of the percentage of PMS. Mediation analysis was performed using the bias-corrected bootstrap approach with 5000 resamples in order to obtain estimates of total, direct, and indirect effects of z-scores of the percentage of PMS on 20-m shuttle-run performance mediated by fat mass. RESULTS: The results show that fat mass mediated the negative effect of biological maturation on 20-m shuttle-run performance in the observed sample of prepubescent girls (Indirect effect: ß = -0.177, 95%CI: -0.291 to -0.059). CONCLUSION: Although the participants were prepubescent girls, poorer aerobic running performance appeared to be partly due to increased levels of fat mass.

Biocultural correlates of gross motor coordination in prepubescent children: A cross-sectional study.

AIM: This study aimed to explore the association of gross motor coordination (GMC) with a matrix of biocultural factors in prepubescent children, taking into account weight status, somatic maturation, sociodemographic variables, and type of school. METHODS: One hundred twenty-nine prepubescent children, of both sexes, aged between 8.00 and 8.99, were assessed for GMC (Körperkoordinationstest Für Kinder - KTK), weight status, biological maturation (predicted mature stature), sex, mother's education level and type of school. Binary logistic regression was used to examine the relationship between higher values of KTK and associated biocultural factors. RESULTS: Normoponderal children are more likely to attain better total KTK scores than those with overweight or obesity (OR: 2.942; LC 95%: 1.189, 7.280). In addition, children who are more advanced in terms of biological maturation exhibited significantly lower odds of being in the high KTK category than their less advanced peers (OR: 0.670; LC 95%: 0.474,0.946). Sex, mother's education level and the type of school are not associated with higher performance on KTK. CONCLUSION: Weight status and biological maturation are associated with motor competence in prepubescent children. Future studies should consider additional correlates to better understand the complex interactions between biological, psychosocial and behavioral factors in the prediction of motor competence.

Age and Maturity Effects on Morphological and Physical Performance Measures of Adolescent Judo Athletes.

Studies assessing age and maturation effects on morphological and physical performance measures of young judokas are scarce. This study aimed to assess the independent and combined effects of chronological age and biological maturation on anthropometry and physical performance of 67 judokas aged 11-14. Participants' anthropometric profiles were assessed, and physical performance tests were completed. Multivariate analyses of variance revealed an independent effect of age (anthropometry: F = 1.871; p < 0.05; Pillai's trace = 0.545; η2 p = 0.272; physical performance: F = 2.876; p < 0.01; Pillai's trace = 0.509; η2 p = 0.254) and maturity (anthropometry: F = 10.085; p < 0.01; Pillai's trace = 0.669; η2 p = 0.669; physical performance: F = 11.700; p < 0.01; Pillai's trace = 0.581; η2 p = 0.581). There was no significant combined effect of age and maturity. The maturation effect remained significant when controlled for age (anthropometry: F = 4.097; p < 0.01; Pillai's trace = 0.481; η2 p = 0.481; physical performance: F = 3.859; p < 0.01; Pillai's trace = 0.0.318; η2 p = 0.318). Inadolescent judokas, the maturation effect on growth and physical performance seems to be more relevant than the age effect, leading to the need to control this effect in training routines and competitive events. As in studies with youth soccer players and other youth athletes, bio-banding can be a strategy for controlling maturation in combat sports.

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

Independent and Combined Effects of Biological Maturation and aerobic performance on the gross motor coordination in prepubertal girls

ABSTRACT The present study analyzed the effect of biological maturation on the performance in the test of gross motor coordination in girls, before and after having its effect controlled by body mass index (BMI) and aerobic performance. The sample was composed by 63 pre-pubertal girls (8.0-8.99 years). The girls who were less advanced in biological maturation presented lower body size and better physical performance in the tasks of walking backward on balance beams (t=2.706; p<0.01; d=0.70), moving sideways on boxes (t=2.128; p<0.05; d=0.48), hopping for height on one leg (t=2.076, p<0.05; d=0.54) and 20-m shuttle run (t=3.162; p <0.05; d=0.61). The maturation no longer influenced performance in the tasks of gross motor coordination when considering BMI and aerobic fitness.

RESUMO O presente estudo analisou o efeito da maturação biológica no desempenho em teste de coordenação motora grossa de meninas, antes e depois de ter seu efeito controlado pelo índice de massa corporal (IMC) e pelo desempenho aeróbio. Participaram 63 meninas pré-puberes de 8,0 a 8,99 anos. As meninas menos avançadas na maturação biológica apresentaram menores dimensões corporais e melhores desempenhos físicos nas tarefas de equilíbrio à retaguarda (t=2,706; p<0,01; d=0,70), transposição lateral (t=2,128; p<0,05; d=0,48), saltos monopedais (t=2,076; p<0,05; d=0,54) e 20-m shuttle run (t=3,162; p<0,05; d=0,61). A maturação deixou de influenciar o desempenho nas tarefas de coordenação motora grossa quando levou-se em consideração o IMC e a aptidão aeróbia.

RESUMEN El presente estudio analizó el efecto de la maduración biológica sobre el desempeño en prueba de coordinación motora gruesa de niñas, antes y después de tener su efecto controlado por el índice de masa corporal (IMC) y por el desempeño aeróbico. Participaron del estudio, 63 niñas pre-puberes de 8 años. Las niñas menos avanzadas en la maduración biológica presentaron menores dimensiones corporales y mejores desempeños físicos en las tareas de equilibrio a la retaguardia (t=2,706; p<0,01; d=0,70), transposición lateral (t=2,128; p<0,05; d=0,48), saltos monopedales (t=2,076; p<0,05; d=0,54) y 20-m shuttle run (t=3,162; p<0,05; d=0,61). La maduración dejó de influenciar el desempeño en las tareas de coordinación motora gruesa cuando se tuvo en cuenta el IMC y la aptitud aerobia.

Sleep, sedentary behavior and physical activity: changes on children's routine during the COVID-19 / Sono, comportamento sedentário e atividade física: mudanças na rotina de crianças durante a COVID-19

Social isolation was adopted as a strategy to reduce the transmission speed of the severe acute respiratory syndrome of coronavirus 2 (SARS-CoV-2) in several countries in the world, including Brazil. As a result, schools were closed and the routines of children altered, affecting sleep, sedentary behavior, and physical activity. The present study aims to compare the children's weekly routine and time spent on sleep, sedentary behavior and physical activity before and during the Coronavirus disease 2019 (COVID-19) pandemic. A cross-sectional study with a quantitative and qualitative approach was performed, with 120 parents, mothers or guardians of children from 5 to 10 years of age of both sexes enrolled in 5 full-time schools in Arapiraca, Alagoas, Brazil. To meet the research objective, two interviews were conducted between 27 May and 5 June, out addressing aspects of sleep, sedentary behavior, and physical activity before and during the COVID-19 pandemic. In the analysis of quantitative data, the paired sample t test was performed, while for qualitative data, discourse analysis was used. Significant differences (p < 0.05) were found in the routine and in sleep time (increase 10%) and screen time (increase 36%) before vs during the COVID-19 pandemic, on weekdays and weekends. There was also a reduction in the practice of physical activity (54%). Therefore, the findings indicate that behaviors during the COVID-19 pandemic could be harmful to children's health and that the school may be an important social environment to protect children from exposure to these behaviors

O isolamento social foi adotado como estratégia para reduzir a velocidade de transmissão da síndrome respiratória aguda grave de coronavírus 2 (SARS-CoV-2) em vários países do mundo, incluindo o Brasil. Como resultado, as escolas foram fechadas e as rotinas das crianças alteradas, afetando o sono, o comportamento sedentário e a atividade física. O presente estudo tem como objetivo comparar a rotina semanal das crianças e o tempo dispendido em sono, comportamento sedentário e atividade física antes e durante a pandemia da doença coronavírus 2019 (COVID-19). Estudo de caráter transversal e com abordagem quanti-qualitativa, com 120 pais, mães ou responsáveis de crianças de 5 a 10 anos de ambos os sexos, matriculadas em 5 escolas de tempo integral de Arapiraca, Alagoas, Brasil. Foram realizadas duas entrevistas, no período de 27 de Maio à 05 de Junho, abordando os aspectos do sono, comportamento sedentário e atividade física antes e durante a pandemia, a fim de atender o objetivo de pesquisa. Na análise dos dados quantitativos foi realizado o teste t de amostra emparelhada, já para os dados qualitativos foi utilizada a análise do discurso. Foram encontradas diferenças significativas (p < 0,05) na rotina e no tempo de sono (aumento de 10%), no tempo de tela (aumento de 36%) antes vs durante a pandemia de COVID-19, em dias de semana e finais de semana. Foi observada também uma redução na prática de atividade física (54%). Portanto, os achados indicam comportamentos durante a pandemia de COVID-19 que podem ser prejudiciais à saúde das crianças e a escola pode ser um ambiente social importante na proteção a exposição de tais condutas