Chloe Harris prefers reading to sport and would rather travel to school by car than walk. Sean Bowden does at least 13 hours of exercise a week, including basketball, football, swimming and PE, and would take on more if his parents let him. Yet analysis indicates that Sean does just one minute more moderate or vigorous physical activity a week than Chloe.
For the past seven years the EarlyBird Diabetes Study, based at Derriford Hospital, Plymouth, has monitored the children’s activity levels and health in an attempt to track the childhood roots of diabetes. It has found, to almost universal astonishment, that children’s activity levels are governed not by the number of PE lessons in the school time-table, or even by the sport they do in their own time, but by an internal mechanism that may be preset before birth. In other words, how much energy children expend may be determined by their genes.