Estudio de los factores ambientales que afectan a la conducta de actividad física en niños y niñas en edad preescolar
Introduction: Physical activity is a health behaviour that brings multiple benefits for the population. In preschool children, physical activity is associated with improvements in body adiposity, bone health, motor skills development, psychosocial health, cognitive development, and cardiometabolic health aspects. Performing such behaviour will depend on several factors, including environmental factors, as well as the time that children spend at the school. General purpose: To know and analyse the factors, mainly environmental ones, that influences physical activity behaviour in preschool-aged children. Development: This doctoral thesis consists of three studies. The first of them is a systematic review which purpose was to come to understand the influence of physical environment on physical activity behaviour, differentiating four domains in which physical activity could be performed (i.e. transport, school, recreation and home). Forty-four articles were finally included in the review and a quality assessment was also performed. In the second and third study, data from 96 preschoolers from four Early Childhood Education institutions in Valencia (Spain) were collected between September 2015 and June 2016. In the second study, with the purpose of understanding the modes of transport to school in this specific population, an analysis of active commuting behaviour and parents’ perceived barriers to active commuting was performed. With that aim, a cross-sectional study was carried out. On the one hand, focus groups with parents were performed to find out which were the modes of transport in this age group and, on the other hand, and adaptation of the BATACE scale was used to identify the parental perceived barriers. This bi-factorial scale measures the perception of environmental/safety and planning/psychosocial barriers to active transport to educational centers. Distance to school was also calculated. Finally, in the third study, the school recess (as an opportunity to be physically active) was analysed. In this study both objective measurements (accelerometers) and direct observations (OSRAC-P) of physical activity were used. Body height and weight were taken and body mass index (BMI; kg/m2) was calculated. BMI percentiles were used to classify children’s weight status. Playground area and density were also measured. Conclusions: The main physical environmental variables that influence physical activity behaviour in preschool-aged children were identified. The most frequently analyzed physical activity domain was the school, followed by recreation, home and transport. In the school, the availability and presence of portable equipment, the presence of certain fixed equipment, and open spaces were identified as health-promoting physical activity factors. No study was found in the Spanish context, what indicates the relevance to conduct studies in any of the domains. In relation to active transport to school, psychosocial and planning barriers were significantly and negatively associated with physical activity, as well as the distance to school. Furthermore, during school recess, children in preschool age showed very little moderate-to-vigorous physical activity and high levels of sedentary behaviour. Positive predictors of moderate-to-vigorous physical activity were: being boy, being a younger preschooler and social interaction during the school recess. Regarding the use of OSRAC-P was found to be a valid system to characterize physical activity patterns in preschool-aged children.