About the project
The project was conducted by researchers at the Department of Nutrition, University of Oslo, and the Norwegian School of Sport Sciences.
The study was conducted at 37 schools in the Eastern part of Norway, starting in the fall 2007 with 6th graders who participated throughout the 7th grade in the spring 2009. Twelve schools received the intervention programme in additon to participating in the data collections, while the remaining 25 schools were controls who participated only in the data collections.
The study was funded by the Norwegian Research Council, and was approved by the Regional Committees for Medical Research Ethics and the Norwegian Social Science Data Service AS.
Objectives
To design, implement and evaluate a comprehensive school-based intervention program to promote healthy weight development among young adolescents (11-13 year olds).
The research hypotheses to be tested in the study were:
- A healthy weight promotion program can be designed and successfully implemented in collaboration with schools, local health care services, community youth organizations and parents.
- A successfully implemented healthy weight promotion program will lead to a more healthy diet and increase physical activity patterns among the children.
- A healthy diet and increased physical activity levels will lead to reduced rates of overweight and obesity among the children.
- The healthy weight promotion program will not contribute to increased rates of unwarranted dieting behaviour among the children, or to increased rates of eating disorders.
Background
Healthy dietary habits and physical activity reduces the risk of overweight and obesity as well as the risk of several non-communicable diseases. School-aged children are an important target group for primary prevention and health promoting activities; habits established in this period of life tend to persist into adulthood.
The intervention program was developed based on a planning model – Intervention Mapping (http://www.interventionmapping.com/), with focus on changing the following behaviours:
- Increase the intake of fruit and vegetables
- Reduce the intake of sugar-sweetened beverages
- Increase physical activity in weekends and on weekdays
- Reduce time spent on TV and PC
Further, it was assumed that these behaviours were influenced by the following potential determinants which the intervention program targeted:
- Awareness of own habits
- Accessibility of healthy foods and possibilities to be physically active
- Clear role models and rules
- Support and encouragement from family, friends and school
The intervention program consisted of:
- A curriculum on energy balance and dietary behaviour (5 lessons, 6th grade)
- Computer tailored personal advise (5 modules, 7th grade)
- Fruit/vegetable and physical activity breaks (one of each weekly)
- Posters (one per month)
- An environmental component including active transport campaigns (3 x 1 week), sports equipment for active recess, and suggestions for easy improvements of schoolyards
- Inspirational courses on physical activity for teachers (1 day per year)
- Fact sheets to parents (one per month)
The effect evaluation on weight development, behaviours and potential determinants was measured at data collections before (fall 2007), during (spring 2008) and after (spring 2009) the intervention among the pupils at both the intervention and control schools. The methods of data collection consisted of questionnaires, objective measures of anthropometrics and physical activity. The process evaluation, which measured the reach and satisfaction with the intervention, was measured with questionnaires to teachers, pupils and parents at the intervention schools in the springs of 2008 and 2009.
Sub-projects
1) Home environmental influences on adolescents’ energy balance related behaviours. The HEIA cohort study.
PhD-student Torunn Holm Totland (2009-)
Funding: Through the National Association of Public Health with aid of EXTRA by the Norwegian Extra Foundation for Health and Rehabilitation
2) Sedentary behaviors, physical activity and dietary behaviors: tracking, change, associated factors and longitudinal associations among Norwegians in the transition into adolescence.
PhD-student Mekdes K. Gebremariam (2010-)
Funding: Norwegian Research Council (grant no. 196931/V50)
Outcomes
Before the intervention (data from fall 2007):
- Prevalence of overweight (incl. obesity) was 15 % among the girls and 14 % among the boys, 30 % among the mothers and 59 % among the fathers. The highest prevalence of overweight – 18.8 % - was seen among children with parents with less than 12 years of education.
- Level of parents’ education (high), frequency of breakfast (high) and moderate to high physical activity were positively associated with being of normal weight, and watching TV was positively associated with being overweight among the adolescents.
- The overweight adolescents were less physically active than the normal weight adolescents. Higher degree of self-efficacy and perceived support from friends was associated with a higher level of physical activity, independent of weight status.
- Intake of soft drinks and squash with sugar was higher on weekends than during weekdays, and the fruit and vegetable intake was low. The higher the education of the parents, the higher the adolescents’ perceived availability of healthy foods (fruit/vegetables), and the lower the perceived availability of unhealthy foods (sugar-sweetened beverages).
During/after the intervention:
- After 8 months of intervention, time spent on TV/DVD and PC/games, and intake of sugar-sweetened beverages during weekends, were significantly lower among the girls in the intervention group compared to the control group.
- After 20 months the intervention did have a small effect on the general physical activity (p=0.05), with the largest effect among the girls, and among those who initially had low levels of physical activity.
- After 20 months beneficial effects on body mass index (BMI) and BMIz score was found among the girls, but not among the boys. While a beneficial effect was found for BMI among adolescents of parents with high education, a negative effect was found for waist-hip ratio among adolescents of parents with low education.
Funding
- Norwegian Research Council (175323/V50)
- Throne Holsts Nutrition Research Foundation, UiO
- Norwegian School of Sports Sciences
Collaboration
Start - slutt
01.06.2006 - 31.08.2012