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Body mass effects of a physical activity and healthy food intervention in middle schools
Leen Haerens1, Benedicte Deforche, Lea Maes
1Department of Movement and Sports Sciences, Ghent University, Belgium. Leen.Haerens@UGent.be
Objective:
To evaluate the effects of a 2-year middle school physical activity and healthy food intervention, including an environmental and computer-tailored component on BMI and BMI z-score in boys and girls.
Research Methods And Procedures:
A random sample of 15 schools with seventh and eighth graders was randomly assigned to three conditions: an intervention with parental support group, an intervention-alone group, and a control group. Weight and height were measured at the beginning and end of each school year to assess BMI and BMI z-score. A physical activity and healthy food program was implemented over 2 school years.
Results:
In girls, BMI and BMI z-score increased significantly less in the intervention with parental support group compared with the control group (p < 0.05) or the intervention-alone group (p = 0.05). In boys, no significant positive intervention effects were found.
Discussion:
This was the first study evaluating the effectiveness of an intervention combining environmental changes with personal computer-tailored feedback on BMI and BMI z-score in middle school children. After 2 school years, BMI and BMI z-score changed in a more positive direction in girls as a result of the intervention with parental support.
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