YOU SEE, you've forgotten about the Olympics already, haven't you? All those medal ceremonies and parades of victorious Brits such as Christine Ohuruogu have faded and we're already thinking of getting the kids' uniform sorted out and your football team facing yet another relegation fight.

Will Team GB's achievement in Beijing have a lasting effect on the nation's health? Will it spur an upsurge of physical activity? This week, the prospect that it would was raised with news that because of the Olympics sales of sports equipment has doubled, bike sales have gone up by 130 per cent, swimsuits and goggles by 135 per cent, and sports bras by 26 per cent.

Sadly, such stories have to be met with some cynicism. We Brits have always been keener on kit than the hard work that should go with it, imagining that a pair of snazzy Speedos will in itself turn us into a Michael Phelps. We've all had the new year fitness splurge that lasts mere days.

The example of Australia, which held the Olympics in 2000, is far from encouraging. Having excelled with 58 medals in Sydney eight years ago, Australia has soared to the top of the world obesity charts, with 60 per cent of the adult population now overweight.

Australian obesity experts have commented that although their Olympics were inspiring for many children, the hard thing was to keep that inspiration going. The Australian effect shows that getting people off their sofas involves far more than parading admirable role models. But they help.

Alarmingly little research has been carried out into what motivates people to exercise.

But what there is indicates that, for adults, the main factors are encouragement, facilities and support close to home. The turn-offs are anxiety about your physique and unrealistic expectations, which, let's face it, may be a genuine prospect when faced with pictures of the Jamaican sprinter Usain Bolt.

In children, the picture is slightly different. Role models do seem to play an important part, but seem to have the most impact if they present an attainable target. A glamorous school swimming captain, for instance, may change behaviour more than Britain's diving prodigy Tom Daley. Whether parents exercise is also highly influential.

What all this tells us is that, once the immediate golden glow of Beijing has worn off, what's really going to have an impact is a sustained effort to make sporting activity easy and the norm - not something for superheroes. Parading the glamour and rewards that sport can bring will work only if it's brought close to home and down to realistic size.

In the run-up to the 2012 Olympics in London, the Government says that it will invest in local facilities such as cycle paths, and give Sport England £400 million to “deliver community sport”. If the money is spent well, and widely, there's a chance that the Team GB spark can be kindled. But the people who really influence our exercise patterns are the role models immediately around us. Producing enough of those (including active parents), and taking the Olympics away from the sofa and into our local sports centre may take a good deal of time.

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