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SUMMARY: The objective of this research is to relate the performance in three vertical jump events with morphological variables of the foot and stature. A total of 177 practitioners of 12 sporting events aged 24.5 ±8.0 years, with 71.01 ±13.00 kg of body mass, 1.71±0.09 m height, and BMI of 24.29±3.24 kg·m-2 were evaluated with an anthropometer in terms of foot length (FL), forefoot width (FW), navicular height (NH), and hindfoot width (HW). These variables were normalized to the height of the subjects. From the footprint record the arch index (AI) was obtained, which indicates the morphology of the medial longitudinal foot arch (MLFA). Performance was evaluated in three vertical jump events: countermovement jump (CMJ), squat jump (SJ), and drop jump (DJ), recording the height reached. FL, FW and HW show a weak positive correlation (r<0.4; p<0.05) with the heights achieved in the three types of jump. The stature is strongly associated with FL, FW and HW (r=0.8; r=0.7 and r=0.6; respectively; p<0.05) and with the height in CMJ, SJ, and DJ (r=0.37; r=0.41 and r=0.32, respectively, p<0.05). The only normalized morphological foot variable that maintained consistency in the correlations analysis was the normalized foot length (NFL) with CMJ (r = 0.2, p<0,05). The subjects whose left foot length was equivalent to 14 % of the stature jumped 27.94 ±6.63 cm, those with 15 % jumped 30.96 ±7.4 cm, and those with 16 % jumped 31.03 ±7.8 cm. FL, FW, HW, and stature are moderately correlated with performance in vertical jump events. However, after discarding the stature of the subjects, only the foot length maintained its relation with performance in CMJ.

RESUMEN: El objetivo de esta investigación fue relacionar el rendimiento en salto vertical con variables morfológicas del pie y estatura. 177 practicantes de 12 disciplinas deportivas de 24,5 ±8,0 años; 71,01 ±13,00 kg; 1,71 ±0,09 m, e IMC de 24,29 ±3,24 kg•m-2 fueron evaluados con un antropómetro obteniendo longitud de pie (FL), ancho de antepié (FW), altura navicular (NH) y ancho de retropié (HW). Estas variables fueron normalizadas a la estatura. Se midió la huella plantar obteniendo el índice del arco (AI), el cual indica la morfología del arco plantar longitudinal medial (MLFA). El rendimiento fue evaluado en tres pruebas de salto: salto con contramovimiento (CMJ), sentadilla con salto (SJ) y salto desde caída (DJ), registrando la altura alcanzada. FL, FW y HW mostraron una débil correlación positiva (r<0,4; p<0,05) con la altura alcanzada en los tres saltos. La estatura se asocia con FL, FW y HW (r=0,8; r=0,7 y r=0,6; respectivamente; p<0,05) y con la altura en CMJ, SJ y DJ (r=0,37; r=0,41 y r=0,32, respectivamente, p<0,05). La única variable normalizada del pie que mantuvo consistencia en el análisis de correlaciones fue la longitud del pie normalizada (NFL) con CMJ (r=0,2; p<0,05). Los sujetos cuyo pie tiene una longitud equivalente al 14 % de la estatura saltaron 27,94 ±6,63 cm, los que equivalen al 15 % saltaron 30,96 ±7,4 cm y quienes tuvieron un pie equivalente a un 16 % de la estatura saltaron 31,03 ±7,8 cm. FL, FW, HW y la estatura se correlacionan moderadamente con el rendimiento en salto vertical. Sin embargo, después de descartar la estatura de los sujetos, solamente la longitud del pie mantiene su relación con el rendimiento en CMJ.

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The aim of the study was twofold: (a) to examine the association between health-related physical fitness and attention capacity in Latin American children and adolescents with overweight and obesity and (b) to test whether body composition outcomes are moderators of this association. A cross-sectional design was used to study 201 overweight/obese participants (12.1 ± 2.1 years of age; 34.3% girls) from Chile (Active-Start study) and Colombia (HEPAFIT study). Body composition, muscular fitness, speed-agility, and cardiorespiratory fitness were evaluated using two similar test batteries (ALPHA and FUPRECOL). Attention capacity was measured by the d2 Test. Linear regression and moderation analyses were conducted. Linear regression analysis revealed an association between muscular fitness (ß = 0.245, P = .015), speed-agility (ß = -0.16, P = .027), cardiorespiratory fitness (ß = 0.331, P < .001) and overall fitness score (ß = 0.210; P = .004) and attention capacity (all analyses were controlled for age, sex, peak height velocity, maternal education, and study setting). Moderation analysis using the Johnson-Neyman technique revealed that the effect of the relationship between muscular fitness score and speed-agility and attention capacity was stronger as fat mass and fat mass index increased. In conclusion, physical fitness components are associated with higher attention capacity in youth with overweight/obesity, but body composition seems to moderate these relationships. Randomized controlled trials in this population would help to better understand whether improvements in different components of physical fitness lead to better attention capacity, especially in youth with excess adiposity.

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The aim of the study was threefold: (a) to test a before-school physical activity intervention (Active-Start) on academic performance, selective attention, and concentration capacity; (b) to test the effect of the Active-Start intervention on anthropometry, body composition, and physical fitness parameters; and (c) whether the physical fitness components are moderators of the effect of the Active-Start program on academic performance, selective attention, and concentration capacity in Chilean children. The Active-Start intervention was a RCT which comprised 170 children (8-10 years old) from three public schools with low socioeconomic status from the city of Santiago (Chile). The exercise intervention was delivered daily, before starting the first school-class (8:00-8:30 am) for 8 weeks. Changes in academic performance, selective attention and concentration capacity, anthropometric, body composition, and physical fitness parameters were measured. The analyses used were mixed regression models for repeated measures over time. No statistically significant changes in attention and concentration capacity were found. However, significant changes were seen in language (0.63; 95% CI 0.49-0.77) and mathematics (0.49; 95% CI 0.32-0.66) performance (P < .001). Also, improvements were seen in fat mass, fat-free mass, muscular, and cardiorespiratory fitness (all P < .05). The Johnson-Neyman technique revealed a significant relationship between the effect of intervention and attention and concentration when change in cardiorespiratory fitness was above, but not below, 3.05 and 0.70 mL/kg/min, respectively. Implementing before-school physical activity programs such as the Active-Start to enhance the cardiorespiratory fitness may benefit attention capacity and academic success among schoolchildren.

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BACKGROUND/OBJECTIVE: To test the effectiveness of an 8-week before-school physical activity program to reduce bullying victimization among a group of socially disadvantaged children in the Active-Start study. METHOD: A non-blinded randomized controlled trial was conducted in three public schools classified as highly vulnerable and located in a deprived area of Santiago (Chile). A total of 5 classes participated, totaling 170 fourth grade children. The intervention was delivered before starting the first school-class (8:00-8:30 a.m.). The program lasted for 8 weeks. Primary outcome measurement on bullying victimization was assessed by the CUBE questionnaire at baseline and post-intervention. RESULTS: There was a statistically significant reduction in the probability of suffering physical bullying (OR= 0.18, 95% CI, 0.04-0.82; p= .027) and verbal bullying (OR=0.13, 95% CI, 0.02-0.97; p= .046) after the 8-week program. CONCLUSIONS: Participation in an 8-week before-school physical activity intervention implemented in schools located in a disadvantaged district in Santiago (Chile) resulted in lower levels of bullying victimization among study participants. The Active-Start program may be a feasible and potentially scalable intervention option to improve the climate and pro-sociality environment at schools.

ANTECEDENTES/OBJETIVO: Evaluar la efectividad de un programa de actividad física antes de la escuela de ocho semanas para reducir el bullying en niños en desventaja social del estudio Active-Start. MÉTODO: Se realizó un ensayo controlado aleatorio no ciego en tres escuelas públicas vulnerables y ubicadas en Santiago (Chile), con un total de cinco clases e incluyendo 170 niños de Cuarto Grado. La intervención de ocho semanas se realizó cinco veces por semana antes de comenzar la primera clase (8:00­8:30 a.m.). La medida de resultado primaria fue la victimización por bullying evaluado a través del cuestionario CUBE al inicio y después de la intervención. RESULTADOS: Hubo una reducción estadísticamente significativa en la probabilidad de sufrir bullying físico (OR= 0,18, IC 95%, 0,04-0,82; p= 0,027) y verbal (OR= 0,13, IC 95%, 0,02-0,97; p= 0,046) después del programa de ocho semanas. CONCLUSIONES: La participación en una intervención de actividad física antes de la escuela de ocho semanas implementada en escuelas ubicadas en una comuna desfavorecida en Santiago (Chile) dio lugar a niveles más bajos de victimización por bullying entre sus participantes. El programa Active-Start puede ser una opción de intervención viable y potencialmente escalable para mejorar el clima y el ambiente escolar.