Study protocol of a population-based cohort investigating Physical Activity, Sedentarism, lifestyles and Obesity in Spanish youth: the PASOS study.

Physical activity (PA) is essential to healthy mental and physical development in early life. However, the prevalence of physical inactivity, which is considered a key modifiable driver of childhood obesity, has reached alarming levels among European youth. There is a need to update the data for Spain, in order to establish if current measures are effective or new approaches are needed. We present the protocol for Physical Activity, Sedentarism, lifestyles and Obesity in Spanish youth (PASOS). This observational, nationally representative, multicentre study aims to determine the PA levels, sedentary behaviours and prevalence of physical inactivity (defined as The study was approved by the Ethics Committee of the Fundació Sant Joan de Déu, Barcelona, Spain. Main findings of the study will be disseminated to the scientific community and to general public by media conferences, social media and a website. ISRCTN34251612