Writing in Swedish daily Dagens Nyheter, footballer Niclas Alexandersson, hurdler Susanna Kallur and ice hockey player Niklas Kronwall have suggested every school should introduce one hour a day of sports.

Ten years ago one in ten Swedish seven-year-olds was overweight or obese - now that figure is one in four. According to a study by the Karolinska Institute in Stockholm, obesity among seven year olds in the capital has increased from 8.5% to 21% over the last fifteen years. During that period, the amount of time given over to sport in Swedish schools has also fallen.

The article, co-written by a number of researchers, doctors and teachers, states that, when it comes to school hours dedicated to sport, Sweden is the fourth worst country in Europe.

Those behind the article argue that exercise and health are becoming class issues, with health problems more common among children from lower social classes.

Schools must take more responsibility, the authors argue, as that is the only place where all children can be reached.

They challenged Schools Minister Jan Björklund to take this into account when he publishes the new curriculum.