The research literature on the effects of physical activity promotion is sparse. One of the few intervention studies on physical activity with school children to report increased endurance fitness and reduced body fat associated with an intensive daily physical program is the Australian Health and Fitness Study. This randomized, controlled trial was designed to compare the effects of integrated physical activity and health education programs on body fat, blood pressure, and endurance fitness in 10-year-old school children in primary schools located in Adelaide. The Oslo Youth Study was successful in designing and implementing within the school system a comprehensive health educational program involving grades 5-7. Positive results were obtained in the intervention group relative to the reference group with reductions in smoking onset, improved eating habits, and increased physical activity over a two-year period.