The purpose of this study is to evaluate the effectiveness of a recreational physical activity intervention (RPAI) for reducing the prevalence of overweight/obesity and other cardiovascular risk factors

The prevalence of overweight in Spanish children in the puberty age is among the highest in the world and increasing quickly. The investigators recently evaluated an after-school program of recreational physical activity to control obesity and other cardiovascular risk factors in primary school children in Cuenca. This program, known as the Movi program, reduced adiposity, increased serum apolipoprotein (apo) A-I concentration and reduced apo B concentration over one-year period.

Though the intervention MOVI had great acceptance between the children and his families, and it demonstrated to be effective opposite to the obesity, his results were relatively modest. For it, our hypothesis of work, which justifies this new project, is that a major intensity of the intervention, and a major weekly duration extending this one to the weekend, it might improve the efficiency on the obesity.

The Boards of Governors (community participatory organ in each school) and the children's parents will inform of the study's aims and methods, and give their written consent to the children's participation. Similarly, the study will present classroom-by-classroom to the children, and their oral consent will obtain. Participant children will be free of serious learning difficulties, or physical or mental disorders, that could impede participation in the scheduled physical activities.