title: Rationale and methods of a randomised cross-over cluster trial to assess the effectiveness of MOVI-KIDS on preventing obesity in pre-schoolers.
abstract: BACKGROUND
  Childhood obesity has become an alarming worldwide increasing public health problem. The earlier adiposity rebound occurs, the greater the risk of becoming obese during puberty and adolescence. It has been speculated about the potential influence of vigorous physical activity on modifying the age of onset of adiposity rebound. Moreover, studies aimed to evaluate the effectiveness of physical activity interventions programs on reducing adiposity and other cardiovascular risk factors in children younger than 6 years are scarce. This paper describes the rationale and methods of a study aimed to test the effectiveness of a two-years multidimensional pre-school intervention on preventing obesity and improving physical fitness during the adiposity rebound period.
  
  
  METHODS
  Twenty-one schools from the provinces of Cuenca and Ciudad Real, Spain, were randomised to an intervention and a control arm. In the first academic year, children in third grade of pre-school and first grade of primary school in the intervention group received the physical activity intervention (MOVI-KIDS). After an academic year schools were crossed over to the alternative arm. According to the socio-ecological model, the intervention included children, their parents and teachers, and the school environment where MOVI-KIDS was conducted. MOVI-KIDS consisted of: i) three-h/week sessions of recreational non-competitive physical activity in after-school time; ii) educational materials to parents and teachers about physical activity benefits and sedentary lifestyle risks; and iii) modifications in the playground to promote physical activity during recess. Baseline and post-intervention outcomes are going to be measured in both arms three times, at the beginning and at the end of first academic year, and at the end of the second academic year. Primary outcomes included body mass index, waist circumference, triceps skinfold thickness, percentage of both body fat and fat-free mass, and blood pressure. Secondary end points were physical activity, fitness, and carotid intima-media thickness.
  
  
  CONCLUSIONS
  This paper reports the design of a randomised cross-over cluster trial aimed at assessing the effectiveness of the multidimensional physical activity intervention (MOVI-KIDS) during two years in pre-school children.
  
  
  BACKGROUND
  Clinical trials.gov: NCT01971840 . (Date of registration: Initial Release: 10/07/2013; Record Verification: 23/10/2013).
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Vicente.Martinez@uclm.es.|Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago de Chile, Chile. Vicente.Martinez@uclm.es.
authors.forename: Vicente
authors.initials: V
authors.lastname: Martínez-Vizcaino
authors.affiliation: Research Centre in Physical Activity, Health and Leisure, Faculty of Sport, University of Porto, Porto, Portugal. jmota@fade.up.pt.
authors.forename: Jorge
authors.initials: J
authors.lastname: Mota
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Montserrat.Solera@uclm.es.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Solera-Martínez
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Blanca.Notario@uclm.es.
authors.forename: Blanca
authors.initials: B
authors.lastname: Notario-Pacheco
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Natalias.Arias@uclm.es.
authors.forename: Natalia
authors.initials: N
authors.lastname: Arias-Palencia
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Jorge.Canete@uclm.es.
authors.forename: Jorge Cañete
authors.initials: JC
authors.lastname: García-Prieto
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Alberto.Gonzalez@uclm.es.
authors.forename: Alberto
authors.initials: A
authors.lastname: González-García
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Celia.Alvarezbueno@uclm.es.
authors.forename: Celia
authors.initials: C
authors.lastname: Álvarez-Bueno
authors.affiliation: Health and Social Research Centre, Universidad de Castilla-La Mancha, Edificio Melchor Cano, C/ Teresa Jornet s/n 16071, Cuenca, Spain. Mairena.Sanchez@uclm.es.|Facultad of Education, Universidad of Castilla-La Mancha, Ciudad Real, Spain. Mairena.Sanchez@uclm.es.
authors.forename: Mairena
authors.initials: M
authors.lastname: Sánchez-López
mesh_terms: D001794:Blood Pressure; D015992:Body Mass Index; D001837:Body Weights and Measures; D002318:Cardiovascular Diseases / Q000517:prevention & control; D059168:Carotid Intima-Media Thickness; D002648:Child; D002675:Child, Preschool; D018592:Cross-Over Studies; D004777:Environment; D015444:Exercise; D005260:Female; D006293:Health Promotion / Q000458:organization & administration*; D006801:Humans; D008297:Male; D009765:Obesity / Q000517:prevention & control*; D010290:Parents / Q000193:education; D010809:Physical Fitness; D012307:Risk Factors; D012574:Schools / Q000458:organization & administration*; D057185:Sedentary Behavior; D013030:Spain / Q000453:epidemiology