title: Gender differences on effectiveness of a school-based physical activity intervention for reducing cardiometabolic risk: a cluster randomized trial.
abstract: BACKGROUND
  Studies that have examined the impact of a physical activity intervention on cardiometabolic risk factors have yielded conflicting results. The objective of this study was to assess the impact of a standardized physical activity program on adiposity and cardiometabolic risk factors in schoolchildren.
  
  
  METHODS
  Cluster randomized trial study of 712 schoolchildren, 8-10 years, from 20 public schools in the Province of Cuenca, Spain. The intervention (MOVI-2) consisted of play-based and non-competitive activities. MOVI-2 was conducted during two 90-minute sessions on weekdays and one 150-minute session on Saturday mornings every week between September 2010 and May 2011. We measured changes in adiposity (overweight/obesity prevalence, body mass index [BMI], triceps skinfold thickness [TST], body fat %, fat-free mass, waist circumference) and other cardiometabolic risk factors (LDL-cholesterol, triglycerides/HDL-cholesterol ratio, insulin, C-reactive protein and blood pressure). The analyses used mixed regression models to adjust for baseline covariates under cluster randomization.
  
  
  RESULTS
  Among girls, we found a reduction of adiposity in intervention versus control schools, with a decrease in TST (-1.1 mm; 95% confidence interval [CI] -2.3 to -0.7), body fat % (-0.9%; 95% CI -1.3 to -0.4), waist circumference (-2.7 cm; 95% CI -4.5 to -0.9), and an increase in fat-free mass (0.3 kg; 95% CI 0.01 to 0.6). The intervention also led to lower serum LDL-cholesterol and insulin levels. Among boys, a reduction in waist circumference (-1.4 cm; 95% CI -2.6 to -0.1; P = 0.03), and an increase in fat-free mass (0.5 kg; 95% CI 0.2 to 0.9; P = 0.003) was associated with the intervention versus control schools. The prevalence of overweight/obesity or underweight, BMI, and other cardiometabolic risk factors was not modified by the intervention. No important adverse events were registered.
  
  
  CONCLUSIONS
  An extracurricular intervention of non-competitive physical activity during an academic year, targeting all schoolchildren regardless of body weight, is a safe and effective measure to reduce adiposity in both genders and to improve cardiometabolic risk profile in girls.
  
  
  BACKGROUND
  Clinical trials NCT01277224.
authors.affiliation: Social and Health Care Research Center, Universidad de Castilla-La Mancha, Cuenca, Spain. vicente.martinez@uclm.es.|Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, ᅟ, Chile. vicente.martinez@uclm.es.
authors.forename: Vicente
authors.initials: V
authors.lastname: Martínez-Vizcaíno
authors.affiliation: Social and Health Care Research Center, Universidad de Castilla-La Mancha, Cuenca, Spain. mairena.sanchez@uclm.es.|School of Education, Universidad de Castilla-La Mancha, Ciudad Real, Spain. mairena.sanchez@uclm.es.
authors.forename: Mairena
authors.initials: M
authors.lastname: Sánchez-López
authors.affiliation: Social and Health Care Research Center, Universidad de Castilla-La Mancha, Cuenca, Spain. blanca.notario@uclm.es.
authors.forename: Blanca
authors.initials: B
authors.lastname: Notario-Pacheco
authors.affiliation: Cuenca I Primary Care Center, Cuenca, Spain. fsalcedo@sescam.org.
authors.forename: Fernando
authors.initials: F
authors.lastname: Salcedo-Aguilar
authors.affiliation: Social and Health Care Research Center, Universidad de Castilla-La Mancha, Cuenca, Spain. montserrat.solera@uclm.es.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Solera-Martínez
authors.affiliation: Hospital Virgen de la Luz, Cuenca, Spain. pfranquelo@yahoo.es.
authors.forename: Pablo
authors.initials: P
authors.lastname: Franquelo-Morales
authors.affiliation: Hospital Virgen de la Luz, Cuenca, Spain. saralopez@yahoo.es.
authors.forename: Sara
authors.initials: S
authors.lastname: López-Martínez
authors.affiliation: Social and Health Care Research Center, Universidad de Castilla-La Mancha, Cuenca, Spain. Jorge.Canete@uclm.es.
authors.forename: Jorge C
authors.initials: JC
authors.lastname: García-Prieto
authors.affiliation: Social and Health Care Research Center, Universidad de Castilla-La Mancha, Cuenca, Spain. Natalia.Arias@uclm.es.
authors.forename: Natalia
authors.initials: N
authors.lastname: Arias-Palencia
authors.affiliation: Social and Health Care Research Center, Universidad de Castilla-La Mancha, Cuenca, Spain. coraltn88@hotmail.com.
authors.forename: Coral
authors.initials: C
authors.lastname: Torrijos-Niño
authors.affiliation: Exercise Physiology Laboratory, Universidad de Castilla-La Mancha, Toledo, Spain. Ricardo.Mora@uclm.es.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Mora-Rodríguez
authors.affiliation: Department of Preventive Medicine and Public Health, School of Medicine, Universidad Autónoma de Madrid, Madrid, Spain. Fernando.artalejo@uam.es.
authors.forename: Fernando
authors.initials: F
authors.lastname: Rodríguez-Artalejo
mesh_terms: D000273:Adipose Tissue; D050154:Adiposity; D001794:Blood Pressure; D015992:Body Mass Index; D001835:Body Weight; D002097:C-Reactive Protein; D002318:Cardiovascular Diseases / Q000517:prevention & control*; D002648:Child; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D016000:Cluster Analysis; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D024821:Metabolic Syndrome / Q000517:prevention & control*; D009043:Motor Activity; D009765:Obesity / Q000517:prevention & control; D010349:Patient Compliance; D012307:Risk Factors; D040242:Risk Reduction Behavior; D012574:Schools; D012737:Sex Factors; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood; D055105:Waist Circumference
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007328:Insulin; D014280:Triglycerides; D002097:C-Reactive Protein