Even school children as young as 11 can cut the levels of several known risk factors for cardiovascular disease if they undergo a daily exercise regimen.
Started four years ago in the German city of Leipzig, the study has already shown that kids assigned to daily exercise lessons reduced their overall prevalence of obesity, improved their exercise capacity, increased their levels of HDL-cholesterol, and reduced their systolic blood pressure.
"It's clear that children today have different lifestyles from the past. They're less active, and it was our hypothesis that an increase in their exercise activity would result in fewer risks of cardiovascular disease later in life," says researcher Dr. Claudia Walther, from the Heart Centre of the University of Leipzig.
The study, whose first-year results are reported at EuroPRevent 2009, randomised 188 school children with a mean age of 11.1 years from three different high schools to either an active exercise programme in their school routine, or to a conventional curriculum of just two sports lessons a week.
The exercise programme comprised daily-supervised exercise that included at least 15 minutes of endurance training.
"So it was well controlled," says Dr. Walther, "with the teachers making sure that the programme was followed."
The first results of the study show that, in just one year, the proportion of overweight and obese children decreased from 13 to 9 per cent, but increased in the control group from 11 to 13 per cent. The researchers also found exercise capacity to significantly improve in the exercise groups by 29 per cent.
Similarly, levels of HDL-cholesterol and of triglycerides, and systolic blood pressure all improved in the exercise group.
"Even from these first-year results we can say that regular physical activity has a significant beneficial effect on body composition, exercise capacity and cardiovascular risk markers in children," says Dr Walther, who adds that follow-up over the next 10-20 years will give some idea of how risk modification at this young age translates into benefit later in life.
According to the researcher, the "most surprising" result was the effect of daily exercise on body weight, an effect not found so marked or so soon in other studies.
"These are normal children, so we didn't expect such a significant reduction in the overall prevalence of obesity or excess weight," she said.
Such findings have also raised local interest in Germany, where the investigators hope to extend the study to other neighbouring towns, and eventually to a daily exercise programme incorporated into the basic school curriculum.
"It's so easy. All it needs is a little more time allocated to exercise lessons. The teachers are there, they supervise, and they all seem enthusiastic. If we can include daily exercise in the school curriculum, I'm sure we'll see an effect," says Dr. Walther.