The first aim was to compare differences between school vulnerability groups, fitness levels, and their combination in adolescent cognitive performance. The second aim was to determine the mediation role of fitness in the association between school vulnerability and cognitive performance. A total of 912 Chilean adolescents aged 10–14 years participated in this study. The school vulnerability index (SVI) assigned by the Chilean Government was categorized into high-, mid-, or low-SVI. Adolescents were classified as fit or unfit according to their global fitness z-score computed from their cardiorespiratory (CRF), muscular (MF), and speed/agility fitness (SAF) adjusted for age and sex. A global cognitive score was estimated through eight tasks based on a neurocognitive battery. Covariance and mediation analyses were performed, adjusted for sex, schools, body mass index, and peak high velocity. Independent analyses showed that the higher SVI, the lower the cognitive performance (F(6,905) = 18.5; p < 0.001). Conversely, fit adolescents presented a higher cognitive performance than their unfit peers (F(5,906) = 8.93; p < 0.001). The combined analysis found cognitive differences between fit and unfit adolescents in both the high- and mid-SVI levels (Cohen’s d = 0.32). No differences were found between fit participants belonging to higher SVI groups and unfit participants belonging to lower SVI groups. Mediation percentages of 9.0%, 5.6%, 7.1%, and 2.8% were observed for the global fitness score, CRF, MF, and SAF, respectively. The mediation effect was significant between low- with mid-high-SVI levels but not between mid- and high-SVI levels. These findings suggest that an adequate physical fitness level should be deemed a protective social factor associated with bridging the cognitive gap linked to school vulnerability in adolescents. This favourable influence seems to be most significant in adolescents belonging to a more adverse social background.

Objetivo: Analizar si el tiempo de pantalla se relaciona con un menor rendimiento académico en escolares de segundo ciclo y determinar diferencias por sexo.Sujetos y Método: Investigación analítica, retrospectiva y transversal en 733 escolares de 5to a 8vo año básico de establecimientos educacionales públicos pertenecientes al estudio “Encuesta de salud y rendimiento escolar de la provincia del Biobío 2018” fueron reclutados. El uso de pantalla fue auto-reportado a través de horas diarias frente a televisión, videojuegos e internet. El rendimiento escolar fue medido con las calificaciones en las asignaturas de lenguaje, matemáticas, educación física, promedio general y a través de conductas asociadas a la cognición en el contexto escolar. Para determinar la relación entre tiempo de pantalla y rendimiento escolar se determinó el coeficiente de correlación de Pearson y para medir la influencia del sexo y las horas de pantalla en las notas se realizó un ANOVA de dos vías.Resultados: Los escolares pasan 6,1 ± 5,3 h frente a una pantalla diariamente. Los niños pasan más tiempo jugando videojuegos y las niñas más navegando por internet. Tanto niños como niñas que pasan mayor cantidad de horas frente a una pantalla, principalmente jugando videojuegos y navegando por internet presentaron notas más bajas en matemáticas, lenguaje, educación física, promedio general y se perciben con menos memoria, más lentos para resolver problemas matemáticos, con más dificultades para mantener la atención en clases o para resolver tareas complejas.Conclusión: El uso de pantallas se asocia negativamente con el rendimiento académico, así como en las conductas asociadas a la cognición en escolares de ambos sexos.

ObjectiveThe aim of this study was to compare academic achievement, cognitive performance, playtime, bullying, and discrimination in adolescents according to traditional uniforms (TUs) and sports uniforms (SUs) worn at school, while simultaneously exploring the influence of the school vulnerability index.MethodsA total of 988 Chilean adolescents (52.6% boys) aged 10–14 years participated in this cross-sectional study. Academic achievement was evaluated by the average grade in maths, language, and science grades, while cognitive performance was assessed through eight cognitive tasks. TUs affecting physical activity, playtime, bullying, and discrimination were queried. Mixed model analyses were performed.ResultsNo differences were observed in academic achievement (TU: 5.4 ± 0.1 vs. SU: 5.5 ± 0.2, p = 0.785) or in cognitive performance (TU: 99.6 ± 0.8 vs. SU: 98.9 ± 1.8, p= 0.754) according to the school uniformtype. Moreover, 64.1 % of participants declared that wearing TU affects their physical activity (traditional uniforms: + 8 min and sports uniforms: + 20 min), and those who believed so spent more time playing than those who answered negatively (14.5 min, p = 0.012). Finally, adolescents wearing SU displayed a lower feeling of bullying and discrimination; this finding depended mainly on the school's vulnerability.ConclusionIt is concluded that wearing TU does not show an educational advantage at an academic and cognitive level that justifies its obligation. In addition, it could be suggested that schools consider adolescents' opinions in adopting a more comfortable uniform, such as the SU. This feasible and low-cost measure would help to increase adolescents' physical activity during the school day, and, contrary to belief, it would not be related to increased feelings of bullying and discrimination.

Objective: To analyze the relationship between anxiety, self-esteem, happiness index and primary school students’ academic performance in Chilean adolescents from the Biobío province. Methodology: 733 (46.1% girls; 12 (1.3 years)) public primary school students that completed the 2018 Health and School Performance Survey carried out in the Biobío province were included in this cross-sectional analysis. The BECK Anxiety Inventory (BAI) was used to measure anxiety while happiness index and self-esteem were measured using the subjective happiness scale and the Rosenberg self-esteem scale, respectively. School performance was measured by grade point average (GPA) of language, math, physical education and cumulative GPA, and behavior associated with cognition in the school context was also considered. The relationship between mental health indicators and school performance was investigated using a one-way ANOVA and Pearson correlation. Results: In comparison to students with low anxiety levels and high self-esteem and happiness levels, students with higher anxiety levels, lower self-esteem and happiness levels perceived themselves as having memory problems. They were also slower to solve math problems, had a shorter attention span in class and presented more difficulties in solving complex tasks, as well as being more nervous during testing. These students also got the lowest grade point average in math, language and physical education. Conclusions: High anxiety levels, low self-esteem and low happiness levels were associated with lower school performance and weaker behavior associated with cognition in Chilean adolescents. Implementing plans of emotional education and mental health could improve academic achievement.

Un estilo de vida saludable conlleva grandes beneficios y es un agente protector frente a enfermedades crónicas. El objetivo fue analizar los hábitos de vida saludable de actividad física, alimentación, sueño y consumo de tabaco y alcohol, en escolares adolescentes chilenos. Este estudio transversal y descriptivo, contó con una muestra aleatoria de 2116 adolescentes chilenos (830 hombres de 15,94 años ±1,20 y 1286 mujeres de 16,09 años ±1,29). Se aplicó el IPAQ corto y un cuestionario sociodemográfico en 19 centros de 5 regiones del país. Se desarrolló un análisis descriptivo empleando tablas de contingencia con prueba de Chi – cuadrado. Resultados: se obtiene un 20,8% de la muestra tiene un nivel de actividad física alto y un 19,5% bajo, siendo mayor en los hombres (χ²= 109.260 p-0,000). Los estudiantes pasan un promedio de 7 horas/día sentados y únicamente el 13.5% accede a la escuela caminando o en bicicleta. Un 18,7% afirma fumar, relacionándose significativamente con las mujeres con nivel de actividad física bajo (χ² 9,343 p-0,009). El 43.5% duerme menos de 8 horas y el 26.4% consume alcohol. Un 41% no desayuna y al analizar por nivel de actividad física y género, observamos diferencias significativas en los hombres (χ² 13,684 p-0,001), donde el hábito de desayunar se asocia a un mayor nivel de actividad física alto. En conclusión, las características evidencian un estilo de vida inadecuado para la edad de la población.