London 2012's legacy: No more UK couch potatoes or another Olympic 'white elephant'?

/ Source: NBC News

It is comfortably one of the fattest nations on the planet, a country where one in five admits they take a 20-minute walk "."

But Britain's couch potatoes appear to be rising from their customary slouched position amid national euphoria over the success of Team Great Britain at the Olympics.

London 2012, which adopted the slogan "Inspire a Generation," made much of its desire to leave behind a genuine Olympic "legacy" as it bid to host the Games. And the early signs appear good for one major strand of that -- to revitalize sports in the U.K. – with some already reporting dramatic increases in interest.

But London 2012 was also designed to help regenerate parts of East London, home to some of the poorest areas in the country. And one expert questioned whether the Olympic Park will become one of city's biggest tourist attractions as hoped or become another example of an Olympic "white elephant."

Few Games in the past have been deemed an economic success. The 1992 Barcelona event is credited with turning an industrial backwater into one of the most popular cities for tourists to visit in the world and slashing employment, .

However, other Olympics turned into financial nightmares -- Canada's Quebec province only finished paying for

And just four years on from the Beijing Games, only 12 events were held at the $500-million Bird’s Nest stadium last year, which was used as an ice-staking rink during the winter, . It addeed that the stadium was “relatively busy compared with other stadiums built for the Olympics.”

So the current mood in the U.K. might have been different if there had been a repeat performance of the 1996 Atlanta Games, when Team GB won one gold, coming behind poorer, less populous countries like North Korea and Kazakhstan in the medal standings.

But just 16 years later and , the third highest total behind China and the U.S.

'Fan the flames'
British rower Greg Searle, a three-time Olympic medalist, told that London 2012 should be measured on whether it had created interest in sports "people have never seen before" and inspired people like his 11-year-old daughter.

"This fire is going to be burning, we need to fan the flames," Searle added. "Getting these things [sports] to continue after the Games has happened, to me, that's what'll be the true test -- if we're talking about this in 20 or 30 years' time because people are still interested in handball and in water polo."

More than half of Team GB's gold medals have come in two sports: rowing, with four, and cycling, with eight.

Rich Stock, program manager of a British Rowing project designed to boost participation in the sport, said that the impact of the Olympics had been immediate and striking.

He told NBCNews.com that on a normal day about 150 people used the club-finder facility on British Rowing's website. But, on the day that Helen Glover and Heather Stanning won gold for Britain in the women's pair race, he said it had been used 5,500 times.

"We've seen a fantastic level of interest," Stock said. "Our clubs are just inundated now... and I think with any sport the more people you have participating, the more chance you have of finding this top-level athletes."

He said that a large number of new rowers were 30- to 40-year-olds who just wanted “to get out on the water and enjoy it,” rather than seeking Olympic glory, and some were in their 80s.

British Cycling, which offers insurance and other cycling-related benefits, broke its record for the highest number of new members in a month with some 2,400 people joining in July, when Bradley Wiggins won the Tour de France and Lizzie Armitstead won silver in the Olympic women's road race.

British Cycling's chief executive Ian Drake said in a statement that he believed

There are also signs of greater interest in other Olympic sports with clubs such as the athletics club, , both in northwest England, and in London reporting rises in the numbers of people wanting to use their facilities.

The Games' economic legacy perhaps hangs in the balance.

The Olympic Park will be turned into the Queen Elizabeth Olympic Park at a cost of nearly $470 million with much of the facilities, such as the main stadium, aquatics center and cycling velodrome, remaining. It is hoped that some 9 million people a year will visit.

Computer-generated images show how the Olympic Park may look in 2014, left, and 2030.

, which will take over the site later this year, the park “will be an exciting new visitor destination. Iconic venues and attractions will sit alongside new homes, schools and businesses, amongst open green spaces and pieces of art in the heart of London’s East End.” As many as nine million visitors a year are expected.

The Athletes’ Village will be turned into homes and thousands of new houses and businesses will be built in the area. The corporation expects more than 10,000 jobs to be created. The basketball stadium, meanwhile, will be packed up and possibly re-used at the Rio de Janeiro Games in 2016.

Peter Tudor, head of venues at the corporation, told NBCNews.com that tourists would be attracted by the Olympic museum, the “beautiful gardens,” bird-watching opportunities, and events such as music concerts at the venues.

“The park is absolutely chock-full of art,” he added, saying Anish Kapoor’s ArcelorMittal Orbit tower/sculpture was not the only work on display. “It’s amazing actually, you walk around at the moment and you kind of bump into art.”

However, Alan Bairner, professor of sport and social theory at the U.K.'s Loughborough University and author of a book, "The Politics of the Olympics," was skeptical.

He said the Olympic stadiums at Stockholm and Helsinki had become "cherished landmarks" – but these were closer to the city centers than Stratford, where the main London park is located.

Barcelona was a "glowing example" of how the Games could have a positive economic impact, Bairner said, but he questioned whether visitors to London would come to regard the Olympic Park as a must-see attraction.

"I don't know how many tourists are going to bother going out to Stratford in the years to come. I wonder if there's the possibility of a white elephant there," he said.

And Bairner also doubted the U.K. would pass Greg Searle's test of a lasting legacy, pointing out that Spain occupies a lowly position on the medal table -- with two golds -- just 20 years after winning 13 golds in Barcelona.

"People are inspired for the moment to watch the Olympics on TV to see what happens -- then it just stops," he said. "There will be hardly any reference to the people who won gold medals in rowing. It's unfortunate, but football [soccer] will take over again.

"I'm not sure about this new generation being inspired."

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