The relative age effect on physical fitness in preschool children

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ ¿ = 0.383; F10, 5996 = 369.64; p < 0.001, ¿p 2 = 0.381) and of quarter (Wilks’ ¿ = 0.874; F15, 8276.6 = 27.67; p < 0.001; ¿p 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers

The relative age effect on physical fitness in preschool children

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F10,5996 = 369.64; p < 0.001, ηp 2 = 0.381) and of quarter (Wilks’ λ = 0.874; F15,8276.6 = 27.67; p < 0.001; ηp 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers

Prenatal predictors and physical fitness in Spanish Youth: the UP&DOWN study

BACKGROUND: Physical fitness outcomes are considered major health biomarkers to assess and monitor exercise-based interventions across the lifespan. Recent studies provide evidence that many adult and childhood chronic diseases should have their origins in gestational or fetal life. To date, a few pioneering studies have showed associations between prenatal predictors and selected physical fitness tests (strength and cardiorespiratory). Nevertheless, there is a lack of knowledge about the influence of prenatal factors on childhood performance on a comprehensive fitness test battery including speed and coordination. The innovative purpose of the current study is to analyse the relative weight of prenatal predictors on schoolchildren's physical fitness outcomes. METHODS: We obtain data from1188 children (571 girls) aged 6-11 years and 1020 adolescents (495 girls) aged 12-17 years. Prenatal predictors (gestational anemia, gestational diabetes and length of gestation) were self-reported from offspring's mothers. The ALPHA fitness test battery for youth was used to assess offsprinǵs physical fitness (muscular strength, motor fitness and cardiorespiratory fitness). Regression analysis were performed to predict the different physical fitness outcomes. RESULTS: The main findings of the present study indicate that the presence of gestational anemia significantly predicted lower scores of lower-body explosive muscular strength (standing long jump) and motor fitness (4x10-m shuttle run) and predicted moderately lower scores of upper-body isometric muscular strength (handgrip strength test). (p>.005; p>.008; p>.075 respectively). Moreover, gestational anemia better predicted lower scores of muscular strength and motor fitness in children than in adolescents (standing long jump, handgrip strength test, 4x10-m shuttle run) (p>.001; p>.051; p > 0.18, respectively). While gestational age and length of gestation (>34- ?42 weeks) predict better cardiorespiratory fitness (20 m shuttle-run test) (p>.023; p>.023 respectively) and motor fitness (4x10 m shuttle; moderately for length of gestation). (p>.020; p > 0.55 respectively). CONCLUSION: This evidence suggests that preventive strategies by health-care institutions, policy makers and technicians must be two-fold: a) to effectively reduce gestational anemia in order to prevent offsprinǵs predisposition to low levels of physical fitness, and b) to intervene with toddlers and children at risk to provide tailored physical activity programs and regular physical fitness evaluation

A longitudinal gender perspective of well-being and health in spanish youth: the UP&DOWN study

Previous studies have observed a link between gender and well-being and health in young populations. The purpose of this research was twofold: (1) to analyse the cross-sectional relationship between gender status with well-being indicators and self-perceived health in adolescents at baseline and at 2-year follow-up and (2) to evaluate the prospective associations between gender at baseline and well-being indicators/self-perceived health assessed at 2-year follow-up. Well-being was measured using the KIDSCREEN-10 questionnaire (as a measure of health-related quality of life (HR-QoL)), the Children's Hope Scale and the Positive and Negative Affect Schedule. Health status of the adolescents was assessed using self-perceived health. Multilevel mixed-effects linear/logistic regression models were carried out to assess the associations between gender status and well-being and health of a sample of 1590 Spanish adolescents. Adolescent girls were shown to have lower HR-QoL scores and higher negative affect scores, and had a higher risk of reporting poor health than boys, in both cross-sectional and longitudinal analyses. Adolescent girls seem to be more vulnerable to poorer well-being and self-reported health than boys. When looking at hedonic and eudemonic well-being separately, longitudinal differential evolution of boys and girls seems to indicate greater deterioration of hedonic well-being among girls as compared to boys. Overall, gender may have a relevant impact on mental and physical health during adolescence.Ministerio de Ciencia e Innovación (DEP 2010-21662-C04-00)7.521 Q1 JCR 20211.698 Q1 SJR 2021No data IDR 2021UE

Independent and combined influence of neonatal and current body composition on academic performance in youth: The UP & DOWN Study

The objective of this study was to examine the independent and combined associations between neonatal and current body composition with academic performance among youth. This cross-sectional study was conducted with a total of 1557 youth (745 girls) aged 10.4 ± 3.4 years. Birth weight and length at birth were self-reported. Current body composition was assessed by body mass index (BMI), waist circumference (WC) and percentage of body fat (BF%). Academic performance was assessed through schools records. Birth weight was related to all academic variables in boys, independent of potential confounders, including BMI; whereas WC, BMI and BF% were related to all academic performance indicators in both boys and girls, independent of potential confounders, including birth weight (all P < 0.05). In addition, the combined adverse effects of low birth weight and current overweight on academic performance were observed in both boys and girls for grade point average (GPA) indicator. Boys in the group with none adverse effect had significantly higher scores in GPA (score +0.535; 95% confidence interval, 0.082–0.989) than boys in the group of both adverse effects (P < 0.007); among girls, GPA score was higher in the group with none adverse effect than in the groups with one or two adverse effects (P for trend = 0.029). Neonatal and current body composition, both independently and combined, may influence academic performance in youth.Sin financiación3.689 JCR (2015) Q1, 8/120 PediatricsUE

Objectively measured physical activity has a negative but weak association with academic performance in children and adolescents

AIM: There is an emerging body of evidence on the potential effects of regular physical activity on academic performance. The aim of this study was to add to the debate, by examining the association between objectively measured physical activity and academic performance in a relatively large sample of children and adolescents. METHODS: The Spanish UP & DOWN study is a 3-year longitudinal study designed to assess the impact, overtime, of physical activity and sedentary behaviours on health indicators. This present analysis was conducted with 1778 children and adolescents aged 6-18 years. Physical activity was objectively measured by accelerometry. Academic performance was assessed using school grades. RESULTS: Physical activity was inversely associated with all academic performance indicators after adjustment for potential confounders, including neonatal variables, fatness and fitness (all p < 0.05). This association became nonsignificant among quartiles of physical activity. There were only slight differences in academic performance between the lowest and the second quartile of physical activity, compared to the highest quartile, with very small effect size (d < 0.20). CONCLUSION: Objectively measured physical activity may influence academic performance during both childhood and adolescence, but this association was negative and very weak. Longitudinal and intervention studies are necessary to further our understanding.Plan Nacionla ed I+D: DEP 2010-21662-C04-00 (DEP 2010-21662-C04-01, DEP 2010-21662-C04-02, DEP 2010-21662-C04-03, DEP 2010-21662-C04-04)1.674 JCR (2014) Q2, 52/120 PediatricsUE

Objectively measured and self-reported leisure-time sedentary behavior and academic performance in youth: The UP&DOWN Study

The objective of this study was to examine the associations of objectively measured and self-reported sedentary behavior during leisure time with academic performance and patterns of sedentary behavior with academic performance. This study was conducted with 1146 youth aged 12.5 ± 2.5 years in Spain during 2011–2012. Leisure-time sedentary behavior during out-of-school hours was assessed by accelerometry and self-report. Academic performance was assessed through school grades.Evaluación de la interacción entre genética y actividad física en el estado físico y la salud en escolares y adolescentes con Síndrome de Down: estudio de seguimiento a tres años Plan Nacional de I+D+i. Ministerio de Ciencia e Innovación (Ref. DEP2010-21662-C04-02).2.893 JCR (2015) Q1, 24/151 Medicine, general & internal, 34/172 Public, environmental & occupational healthUE

Perceived environment in relation to objective and self-reported physical activity in Spanish youth. The UP&DOWN study

The aims of the present study were to assess the association of environmental perception with objective and self-reported physical activity (PA) and the relation between environmental perception and meeting PA recommendations on children and adolescents. A sample of 1520 youth (770 boys) aged 8-18 years (12.1 ± 2.5 years) from the UP&DOWN study were included in the data analyses. Environmental perception was assessed with the short adapted version of the ALPHA environmental questionnaire. PA was objectively (accelerometers) and self-reported measured (PA Questionnaire for Children, Patient-centered Assessment and Counseling for Exercise Questionnaire and Finnish PA Index). Linear regression models were used to assess the association of environmental perception with PA. Bivariate logistic regression models were used to assess differences between environmental perception and meeting PA recommendations. Environmental perception was positively associated with both objective and self-reported PA. Some differences were found in the association of environmental perception and PA between sex-and age-specific groups. Youth who perceived a more favourable environment were more likely to meet PA recommendations (at least 60 min · day− 1 of moderate to vigorous PA (MVPA)). Results suggest that environmental perceptions of children and adolescents may play an important role in achieving higher levels of PA.Plan Nacional de I+D+I MICINN (DEP 2010-21662-C04- 00)2.539 JCR (2016) Q2, 17/81 Sport Sciences1.280 SJR (2016) Q1, 31/280 Orthopedics and Sports Medicine, 18/195 Physical Therapy, Sports Therapy and Rehabilitation, 29/127 Sports ScienceNo data IDR 2016UE

Independent and combined associations of physical fitness components with inflammatory biomarkers in children and adolescents

[Background]: We aimed to examine the independent and combined associations of cardiorespiratory fitness, muscular fitness, and motor ability with single and clustered inflammatory biomarkers in children and adolescents.[Methods]: This study included 503 children and adolescents. Cardiorespiratory fitness, upper- and lower-muscular fitness, and motor ability were assessed using field-based tests. Fasting blood samples were obtained to determine the levels of a set of inflammatory biomarkers. Global physical fitness and clustered inflammatory biomarker scores were computed. Associations between physical fitness and inflammatory biomarkers were analyzed through linear regression. Differences in inflammatory biomarker levels between physical fitness tertiles were tested.[Results]: Global physical fitness was inversely associated with single and clustered inflammatory biomarkers in children (p < 0.05); and with C-reactive protein, complement factor C4, leptin, and clustered inflammatory biomarkers in adolescents (p < 0.025). Cardiorespiratory fitness and upper-muscular fitness were negatively and independently associated with several single and clustered inflammatory biomarkers in children and adolescents (p < 0.05). Differences were found between the lowest and the highest tertiles of global physical fitness in clustered inflammatory biomarker levels (p < 0.010).[Conclusion]: Physical fitness was negatively associated with single and clustered inflammatory biomarkers, independently of body mass index. Increasing physical fitness levels in youth might contribute to reduce the cardiovascular risk.This work was supported by the National Plan for Research, Development, and Innovation (R + D + i) from the Spanish Ministry of Science and Innovation [DEP 2010-21662-C04-00 (DEP 2010-21662-C04-01: DEP 2010-21662-C04-02: DEP 2010-21662-C04-03: DEP 2010-21662-C04-04)]; and by the Spanish Ministry of Education [FPU15/05337].Peer reviewe

Cardiorespiratory fitness cutoff points for early detection of present and future cardiovascular risk in children: A 2-year follow-up study

On behalf of the UP&DOWN Study Group.[Objective]: To examine the association between cardiorespiratory fitness (CRF) at baseline and cardiovascular disease (CVD) risk in 6- to 10-year-olds (cross-sectional) and 2 years later (8- to 12-year-olds [longitudinal]) and whether changes with age in CRF are associated with CVD risk in children aged 8 to 12 years. [Patients and Methods]: Spanish primary schoolchildren (n=236) aged 6 to 10 years participated at baseline. Of the 23 participating primary schools, 22% (n=5) were private schools and 78% (n=18) were public schools. The dropout rate at 2-year follow-up was 9.7% (n=23). The 20-m shuttle run test was used to estimate CRF. The CVD risk score was computed as the mean of 5 CVD risk factor standardized scores: sum of 2 skinfolds, systolic blood pressure, insulin/glucose, triglycerides, and total cholesterol/high-density lipoprotein cholesterol. [Results]: At baseline, CRF was inversely associated with single CVD risk factors (all P0.85; P<.001) and to predict CVD risk 2 years later (P=.004). Persistent low CRF or the decline of CRF from 6-10 to 8-12 years of age is associated with increased CVD risk at age 8 to 12 years (P<.001). [Conclusion]: During childhood, CRF is a strong predictor of CVD risk and should be monitored to identify children with potential CVD risk.This work was supported by grant DEP 2010-21662-C04-00 (DEP 2010-21662-C04-01: DEP 2010-21662-C04-02: DEP 2010-21662-C04-03: DEP 2010-21662-C04-04) from the National Plan for Research: Development and Innovation (R+D+i) MICINN and by grant FPU15/05337 from the Spanish Ministry of Education.Peer Reviewe