New research from the University of Alberta in Canada show that children need just seven minutes of vigorous exercise a day to stay fit. However, most children are failing to achieve this.

More than 600 children between the ages of nine and 17 wore monitors for seven days, which tracked their activity levels. They also had their weight, waist circumference and blood pressure regularly monitored.

Shockingly, almost 70 per cent of their time was spent on sedentary activities, nearly 23 per cent on light physical activity, 7 per cent on moderate physical activity and 0.6 per cent on vigorous activity.

“The research tells us that a brisk walk isn’t good enough,” says co-principal investigator, Richard Lewanczuk. “Kids have to get out and do a high-intensity activity in addition to maintaining a background of mild to moderate activity. There’s a strong correlation between obesity, fitness and activity.”

Overall boys were more active than girls and overweight children showed improved fitness levels, and shrinking waistlines, when they upped their activity.

Lewanczuk emphasises the importance of getting young children active, as activity levels drop sharply in teenage years.

Children are less active at home than at school. “Quite often the activity levels on evenings or weekends would be almost flat. We made the presumption that kids were just sitting in front of a screen the whole time,” he says.

Lewanczuk hopes the research findings will help schools decide on what type of mandatory physical activity is needed.