title: Effects of the Youth Fit 4 Life physical activity/nutrition protocol on body mass index, fitness and targeted social cognitive theory variables in 9- to 12-year-olds during after-school care.
abstract: OBJECTIVE
  Childhood overweight and obesity is unacceptably high in industrialised nations. School-based interventions have largely been atheoretical and ineffective. This study aimed to test a new theory-based protocol for its effects on measures of fitness and body mass index (BMI), and its proposed psychosocial mediators, during elementary after-school (out-of-school hours) care.
  
  
  METHODS
  Nine- to 12-year-old participants of YMCA-based after-school care in the southeastern Unites States were randomised into either the experimental Youth Fit 4 Life (YF4L) treatment group (n = 86) or a typical care group (n = 55) for 45 min/day. YF4L is based on social cognitive theory, emphasising mastery over physical activities and the development of self-management/self-regulatory skills to support healthy behaviours. Physiological and psychosocial variables were assessed over a 9-month elementary school year.
  
  
  RESULTS
  Of the overall sample, 28% were overweight or obese at baseline. YF4L was associated with significantly greater improvements in BMI, and measures of self-regulation, mood, self-efficacy, cardiovascular endurance and strength over both 3 and 9 months. Changes in self-regulation, mood and self-efficacy significantly mediated the treatment type-BMI relationship over both 3 months (R2= 0.12, P = 0.002) and 9 months (R2= 0.13, P = 0.001), with change in self-regulation being a significant independent mediator. Changes in BMI and self-regulation reciprocally reinforced one another. Gender was not a significant moderator of those relationships.
  
  
  CONCLUSIONS
  The YF4L treatment mitigated rise in BMI in 9- to 12-year-old enrollees of after-school care. The treatment's basis in social cognitive theory was supported. Because of its positive effects and ability to utilise existing staff, large-scale application is warranted after sufficient replication.
authors.affiliation: Wellness Department, YMCA of Metro Atlanta, Atlanta, Georgia, United States.|Wellstar School of Nursing, Kennesaw State University, Kennesaw, Georgia, United States.
authors.forename: James J
authors.initials: JJ
authors.lastname: Annesi
authors.affiliation: Department of Surgery, Health Promotion and Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States.|Department of Child Wellness, Children's Healthcare of Atlanta, Atlanta, Georgia, United States.
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Walsh
authors.affiliation: Wellness Department, YMCA of Metro Atlanta, Atlanta, Georgia, United States.
authors.forename: Brittney L
authors.initials: BL
authors.lastname: Greenwood
authors.affiliation: Wellstar School of Nursing, Kennesaw State University, Kennesaw, Georgia, United States.
authors.forename: Nicole
authors.initials: N
authors.lastname: Mareno
authors.affiliation: Wellness Department, YMCA of Metro Atlanta, Atlanta, Georgia, United States.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Unruh-Rewkowski
mesh_terms: D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D015928:Cognitive Behavioral Therapy; D005260:Female; D006293:Health Promotion; D006801:Humans; D008297:Male; D010809:Physical Fitness / Q000502:physiology*; D015397:Program Evaluation; D015144:Southeastern United States
keywords: 
  BMI
  ; after-school care; elementary school; fitness; health behaviour change; out-of-school care