Olympic star Mo Farah and London mayor Boris Johnson have launched a new campaign aimed at getting more children to be active.
The Move It report, written by the Young Foundation, found that while London 2012 provided a fantastic showcase for elite British sport, fewer people are taking part in physical activity.
Move It says that just 5 per cent, or one in 20, of adults are exercising at the government-recommended level of two and a half hours a week.
The London Mayor spoke of the importance of encouraging elite sports which give young people role models to aspire to and encourage it at grassroots levels.
A separate study, Designed To Move, found that today’s children are the first generation to have a life expectancy shorter than their parents and that a nine-year-old today in the UK will be 50 per cent less active by the time they turn 15.
Mo Farah said: “If you don’t do a certain amount of exercise you could have five years less of your life. It important to think about that as a parent.”