Obesidad, actividad física y rendimiento académico en escolares

Resumen

Cognition is a term that includes a high number of underlying mental processes related with acquiring knowledge and understanding through life-long experience; including attention, memory, working memory, judgment and evaluation, reasoning, problem solving, decision making, comprehension and production of language. It could also include academic achievement and classroom behaviours. In the recent years, understanding cognition and its development has become an important health goal. Life expectancy has been increased during last years and this could have a negative effect on individuals’ cognition due to the accumulative effect of diseases and biological changes. This cognitive decline could be partially determined by the early childhood development, in such a way that this status tracks from infancy through adolescence to adulthood. Moreover, the optimal development and acquisition of cognition have been related with proper physical and mental health during childhood. This is why recent research has been focused on how to improve and boost cognitive development since childhood. Physical activity is included among the modifiable environmental factors that could influence the development of children’s cognition, and school-based physical activity programs have been the most worldwide accepted interventions, understanding that school is the ideal place to promote children’s health behaviours and to try to make of them “healthier adults”. Additionally, other factors related to mothers’ and children’s behaviours and characteristics such as pre-pregnancy overweight/obesity, sedentary behaviour during pregnancy, birth weight and children’s cardiorespiratory fitness, have been related with children’s cognition development. Several questions in this regard remain unclear: i) which cognition areas are the most benefited from school-based physical activity programs; ii) which are the physical activity characteristics most closely related to success on promoting cognitive skills development; iii) is there any association between pre-pregnancy weight status or physical activity during pregnancy with offspring’s cognition; iv) are birth weight and cardiorespiratory fitness associated with cognition development in preschool children; and v) is there any mediation role of fitness in the relationship between birth weight and cognition. The objective of this doctoral dissertation is to provide scientific evidence aimed to clarify these important questions, due to the importance of brain development during pregnancy and childhood period. With this aim, several systematic reviews and meta-analysis have been conducted, as well as some analyses of empirical data coming from the MOVI-KIDS project, a cluster randomized trial involving 21 schools from the provinces of Cuenca and Ciudad Real. As result of these research works, this doctoral dissertation allows us to conclude that: i) some cognitive skills, including classroom behaviours and academic achievement, are sensitive to school-based physical activity interventions; ii) the most effective physical activity interventions are those aimed at increase the time of daily exercise, those integrating physical activity during classroom lectures and those aimed at being cognitively demanding; iii) pre-gestational obesity weight status seems to negatively influence on offspring’s neurocognitive development, but a small negative effect on general intelligence. Also, children from active mothers during pregnancy scored better on general intelligence and cognitive skills; and iv) low birth weight and low cardiorespiratory fitness are negatively related with cognition in preschool children, and this relationship is fully and/or partially mediated by children’s birth weight. The research was designed by Vicente Martínez Vizcaíno and Celia Álvarez Bueno, researchers of the Health and Social Research Center (Centro de Estudios Sociosanitarios –CESS-), from Cuenca, Spain. The analysis of the results was coordinated by Caterina Pesce, from the University of “Foro Italico”, Rome, and Celia Álvarez Bueno. Celia Álvarez Bueno has been awarded a scholarship for the completion of this dissertation by the Spanish Ministry of Education, Culture, and Sport (FPU13/03137).