We found strong evidence to support beneficial effects of child obesity prevention programmes on BMI, particularly for programmes targeted to children aged six to 12 years. However, given the unexplained heterogeneity and the likelihood of small study bias, these findings must be interpreted cautiously. A broad range of programme components were used in these studies and whilst it is not possible to distinguish which of these components contributed most to the beneficial effects observed, our synthesis indicates the following to be promising policies and strategies:
·         school curriculum that includes healthy eating, physical activity and body image
·         increased sessions for physical activity and the development of fundamental movement skills throughout the school week
·         improvements in nutritional quality of the food supply in schools
·         environments and cultural practices that support children eating healthier foods and being active throughout each day
·         support for teachers and other staff to implement health promotion strategies and activities (e.g. professional development, capacity building activities)
·         parent support and home activities that encourage children to be more active, eat more nutritious foods and spend less time in screen based activities
However, study and evaluation designs need to be strengthened, and reporting extended to capture process and implementation factors, outcomes in relation to measures of equity, longer term outcomes, potential harms and costs.
Childhood obesity prevention research must now move towards identifying how effective intervention components can be embedded within health, education and care systems and achieve long term sustainable impacts.
Promoting healthy lifestyles among adolescent boys: the Fitness Improvement and Lifestyle Awareness Program RCT.
To assess the feasibility, acceptability, and potential efficacy of a school-based obesity prevention program among adolescent boys with sub-optimal cardiorespiratory fitness.
                In 2007, a 6-month, 2-arm parallel group, randomized controlled pilot trial was conducted in a single school setting (Sydney, Australia). Thirty-three 7th Grade boys (mean age=12.5+/-0.4 years) were randomly assigned to intervention (n=16) or active comparison group (n=17). The intervention consisted of one 60-minute curriculum session and two 20-minute lunchtime physical activity sessions per week. The active comparison group continued with their usual physical activity curriculum sessions (Friday afternoons 2-3 pm). The pilot trial's curriculum sessions were additional to Physical Education (PE) lessons. The primary outcome was BMI, and secondary outcomes included waist circumference, percentage body fat, cardiorespiratory fitness, objectively measured physical activity and small screen recreation time.
                Screening, recruitment and retention goals were exceeded. The majority of data were collected as planned. Implementation and attendance rates were acceptable. At follow-up, compared with boys in the active comparison group, boys in the intervention group displayed a smaller increase in BMI (adjust diff.=-0.2, 95% confidence interval [CI] -0.78, 0.39; Cohen's d=0.05); greater reductions in waist circumference (-1.65 cm [-4.67, 1.36]; d=0.15); percentage body fat (-1.69% [-4.98, 1.60]; d=0.22) and time spent in small screen recreation on weekends (-1.13 h [-5.06, 2.80]; d=0.19); and a greater increase in cardiorespiratory fitness (2.13 laps [6.22, 10.48]; d=0.16); and participation in total weekday physical activity (140.74 counts/min [-159.44, 440.92]; d=0.36).
                This study verified the feasibility, acceptability and potential efficacy of a multifaceted school-based intervention to prevent unhealthy weight gain among adolescent boys.