The study, which was published in the February 2018 issue of the recognised British Journal of Sports Medicine, examined bone and muscle health in 295 schoolchildren from Frederikssund and Copenhagen over a whole school year where the children participated in the 'FIT FIRST' training concept, looking into the effects of various types of intense interval training at school.
This programme was initiated at University of Copenhagen by researchers Professor Peter Krustrup and Assistant Professor Malte Nejst Larsen, now at the University of Southern Denmark, and run in collaboration between sports coaches and schoolteachers.
In the study, the researchers compared the effects on children who took the normal school PE classes with children who had intense exercise on the timetable for two hours a week in the form of ball games on small pitches or 'circuit training' consisting of gymnastic and strength exercises using their own body weight.
"Our research shows that intense exercise at school has clear positive effects on bone density, muscular strength and balance in 8-10-year-old children," says the project leader Peter Krustrup, Professor of Sport and Health Sciences at the University of Southern Denmark.
"In the children in third grade who played ball games three against three or participated in circuit training for 3 x 40 minutes a week, muscular strength increased by 10% and balance improved by 15%, while the children's bone density increased by a whole 45% compared to the control group. These types of sports are great ways for children to "put bone in the bank".
Malte Nejst Larsen, Assistant Professor at the University of Southern Denmark, adds: "The study shows that bone density in the ball-game group rose by 7% in the legs and by 3% in the body as a whole, giving a real boost to bone health. Exercise in school for children aged 8-10 which improves bone density, muscular strength and balance is the first big step towards preventing osteoporosis later in life," he says.