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The relationship between body weight gain and the onset of obesity is linked to environmental and behavioral factors, and may be dependent on biological predisposing. Artificial neural networks are useful predictive tools in the field of artificial intelligence, and can be used to identify risk factors related to obesity. The aim of this study is to establish, based on artificial neural networks, a predictive model for overweight/obesity in children based on the recognition and selection of patterns associated with birth weight, gestational age, height deficit, food consumption, and the physical activity level, TV time and family context. Sample consisted of 149 children (72 = eutrophic and 77 = overweight/obese). Collected data consisted of anthropometry and demographic characteristics, gestational age, birth weight, food consumption, physical activity level, TV time and family context. The gestational age, daily caloric intake and birth weight were the main determinants of the later appearance of overweight and obesity. In addition, the family context linked to socioeconomic factors, such as the number of residents in the household, had a great impact on excess weight. The physical activity level was the least important variable. Modifiable risk factors, such as the inadequate food consumption, and non-modifiable factors such as gestational age were the main determinants for overweight/obesity in children. Our data indicate that, combating excess weight should also be carried out from a social and preventive perspective during critical periods of development, such as pregnancy, lactation and early childhood, to reach a more effective strategy to combat obesity and its complications in childhood and adult life.

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There is only limited evidence to suggest that training during childhood produces greater adaptations than at other ages. The aim of this study was to examine the effects of plyometric training (12 weeks, twice/week, 20 min/day) on physical fitness (PF) and gross motor coordination (GMC) in schoolboys aged 7-9 years. A total of 116 boys were assigned to two groups: plyometric training group (PT,n = 73) and control group (CG,n = 43). The CG maintained their normal daily activities. The PT consisted of twice-weekly exercises on nonconsecutive days for twelve weeks under monitored and controlled conditions. PF (handgrip strength, standing long jump (SLJ), curl-ups, sit and reach, square-test, running speed, and 1 mile run test), GMC, Korper-koordinations-test fur Kinder (KTK), and body mass index (BMI) were assessed. The main results through a 2 × 2 (time × groups) repeated measures analysis variance demonstrated a significant time effect that improves PF and GMC according to the direction of the measure. A group effect was observed only in the abdominal strength test (CG = 12.06% and PT = 17.04%) and moving sideways (CG = 11.1% and PT = 12.4%) showing that independent of the group there was an improvement. A significant interaction effect (time × groups) was observed in the flexibility test (CG = -2.7% and PT = 3.5%) and STJ (CG = 3.1% and PT = 18.5%), as well as jumping sideways (CG = 16.3% and PT = 17.4%) and overall GMC score (CG = 9.8% and PT = 15.9%), showing that gains in these variables were greater in the PT group. The results suggest that 12 weeks of PT improve components of gross motor coordination and health-related physical fitness in children.

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Youth swimming performance may be influenced by anthropometric and body composition factors during growth. Propulsive force of the arm (PFA) is highly related to swimming performance as 85-90% of the propulsive power comes from the arms. The current study analyzed the mediating effect of biological maturation on the relationship between anthropometric variables and body composition with PFA in young swimmers. A total of 128 swimmers [boys: n = 53, age = 13.6 (1.8) y; girls: n = 75, age = 12.5 (1.8) y] were evaluated. Propulsive force of the arm was estimated by the tethered swimming test. Anthropometric characteristics (body mass, stature, sitting height, arm span, arm muscle area, %body fat, and fat-free mass) were evaluated. Biological maturation was estimated by the age of peak height velocity. Mediation analyses were performed using the Preacher and Hayes bootstrapping method, adjusted for chronological age and sex. All anthropometric and body composition variables, except %body fat, were positively associated with PFA, being mediated by biological maturation. Indirect effects and 95% confidence intervals were: body mass [.20 (.09-.34)], stature [.22 (.11-.43)], arm span [0.17 (.05-.31)], arm muscle area [.74 (.38-1.19)] and fat free-mass [.17 (.05-.34)]. In conclusion, biological maturation mediated the positive associations between body size and composition and PFA in young swimmers.

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BACKGROUND: Birthweight (BW) has been associated with anthropometry, body composition and physical fitness during growth and development of children. However, less is known about the mediation effect of those variables on the relationship between BW and basal metabolic rate (BMR) in children. OBJECTIVE: To analyse the mediation effect of anthropometry, body composition and physical fitness on the association between BW and BMR in children. METHODS: In total, 499 children (254 boys, 245 girls) aged 7-10 years were included. Anthropometry (weight, height, head, waist and hip circumferences), body composition (skinfolds thickness, body fat percentage), physical fitness (handgrip strength, flexibility, muscular endurance, muscular explosive power, agility, running speed) and BMR were evaluated. The analyses were conducted by: single-mediator analysis (SMA) and multi-mediator analysis (MMA). RESULTS: The SMA indicates height, head, waist and hip circumferences and handgrip strength as significant mediators of BW on BMR for boys and height, hip circumference and handgrip strength as significant mediators of BW on BMR for girls. In MMA for girls, there were significant indirect effects for height, hip circumference and handgrip strength, with 79.08% of percent mediation. For boys, the head and waist circumferences mediation had a significant indirect effect, with 83.37% of percent mediation. CONCLUSION: The anthropometric variables associated with BW were body height, head, hip and waist circumferences for boys and body height and hip circumference for girls. The current study provides new evidence that height and handgrip strength during childhood mediated the relationship between BW and BMR.

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OBJECTIVES: The increase in the prevalence of overweight/obesity in youth is a public health problem worldwide; however, few studies have investigated its prevalence and correlates in children from the Brazilian Northeast region rural zone. The purpose of this study was (1) to estimate the prevalence of children's weight status according to sex, age, and birth weight categories; and (2) to investigate the links between biological and behavioral factors and weight categories. METHODS: The sample comprises 501 children (248 girls), aged 7-10 years, classified as low weight, normal weight, overweight, and obese using body mass index cut-points. Predicted variables included birth weight, percentage of body fat (%BF), fat free mass (FFM), physical fitness, and gross motor coordination. RESULTS: Data showed differences among weight groups for the predictor variables. Results of the logistic regression revealed that sex, age, %BF, FFM, physical fitness, and motor coordination seem to be relevant predictors of children's weight status, while no significant effect was observed for birth weight. CONCLUSION: Children with lower physical fitness levels as well as those with lower motor coordination quotient are more likely to be overweight and/or obese. No significant relationship was observed between birth weight and weight status in childhood. Strategies to reduce childhood obesity should consider biological, behavioral, and also environmental predictors.

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AIM: The aim of this study was to analyse the influence of birthweight on motor performance and body composition in children. Further, we investigated whether associations between birthweight and motor performance changed after adjustment for current height, body mass index (BMI), fat-free mass (FFM), and % body fat. METHOD: A total of 483 children (251 males and 232 females) aged 7 to 10 years (mean 8.78, SD 1.0y) born in Vitória Santo Antão (northeast Brazil) were sampled. Motor performance was operationalized using different physical fitness components and gross motor coordination. Physical fitness was measured by handgrip strength, muscle endurance, explosive power, flexibility, agility, running speed, and maximal oxygen consumption (VO2max). Gross motor coordination was evaluated by means of the Körper Koordination Test für Kinder (KTK). RESULTS: Positive correlations between birthweight and height, BMI, and FFM were found. Birthweight was positively correlated with handgrip strength and negatively correlated with 20-meter sprint time, even after controlling for age, height, BMI, FFM, and % body fat. Birthweight was negatively associated with relative VO2max (mL/kg/min); however, the association was no longer significant after inclusion of BMI or FFM in the model. INTERPRETATION: Birthweight significantly predicted height, BMI, FFM, and performance in strength and velocity tests, but did not influence gross motor coordination.

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