American swimmer Michael Phelps leaves London as the most decorated Olympian with 22 medals and he can also lay claim to another title - winning most fans on social media during the 2012 Games.

London 2012 has been dubbed the first Social Media Games with the use of Twitter and Facebook exploding since the Beijing Olympics in 2008 and allowing athletes to chat directly with their fans for the first time.

It has also been a testing ground for athletes, managers and sponsors to find out what does and does not work on social media, with two athletes expelled for racist tweets and a teenager arrested for abusing British diver Tom Daley.

"A clear majority of medal winners are actively communicating with their fans through Facebook, Twitter and other networks in London 2012," said Drew Thomson, chief executive of Starcount, the social media tracker.

Figures released to Reuters by Starcount on Friday showed that Phelps added one million Twitter followers at the London Olympics which started on July 27 to bring his total number of followers to 1.2 million and 800,000 Facebook fans.

Jamaica's Usain Bolt, who stormed to gold in both the 100 and 200 meters finals, was second in the list, adding 725,000 followers on Twitter to reach 1.36 million and attracting another 700,000 Facebook fans.

Surge of support

Joint third in the popularity stakes at London were Daley and 16-year-old US gymnast Gabby Douglas, nicknamed "the Flying Squirrel."

Douglas won 600,000 new Twitter followers, helped by two gold medals and an exchange with new fan, singer Justin Bieber, and her Facebook fan count grew to almost 600,000 from 15,000.

Daley, 18, was a favorite with the fans who were quick to come to his defence when he was attacked on Twitter for failing to win a medal in his first event with an Internet troll saying he had let his father down. His father died last year.

The other athletes in the top 10 for gaining fans were British heptathlete Jessica Ennis, Chinese swimmer Sun Yang, US swimmer Ryan Lochte, Chinese hurdler Liu Xiang, badminton player Lin Dan, and US basketball player LeBron James.

Starcount, which pulls data from 11 global social networks to chart activity, also ranked the teams and found the host, Team GB, gained the most followers during the London Games, winning 50,000 Facebook fans and 22,000 Twitter followers.

Lewis Wiltshire, head of sport at Twitter UK, said Twitter had given the Games a new dimension.

He said highlights included Manchester United player Rio Ferdinand chatting with Bolt, Phelps and team mate Ryan Lochte congratulating each other, and Tim Berners-Lee, the inventor of the World Wide Web, live-tweeting from the opening ceremony.

"We have seen athletes sharing photos, answering questions, responding to 'good luck' wishes and talking to fellow stars, all giving fans first-hand insight into their experiences of the Games," Wiltshire told Reuters.

The US 4x100m medley relay team holds a banner thanking host city London, after receiving their gold medals for winning the men's 4x100m medley relay final during the London 2012 Olympic Games at the Aquatics Centre August 4, 2012. Seen are Michael Phelps, Nathan Adrian, Matthew Grevers and Brendan Hansen (Photo: Reuters)

Garry Crawford, senior lecturer in cultural sociology at Salford University, said this link between celebrities and the public was new for many athletes and teams at London.

Two athletes fell foul of Twitter, with Swiss footballer Michel Morganella and Greek triple jumper Voula Papachristou kicked out of the Olympics for racist tweets.

Other athletes referred to Twitter as being a distraction.

"I think we will see more control by managers and agents on Twitter in the future as they have been quite naive over its use and people have been caught out," Crawford told Reuters.

He said the Olympics had been a good testing ground as it was an event concentrated over a limited period of time and with high involvement from all parties.

Leah Donlan, a lecturer on sports marketing at the University of Central Lancashire, said sponsors were also learning how to use social media to their advantage, realizing that corporate talk would not get them followers.

"Companies really were shooting in the dark before the Olympics and I think at future events they will get more creative and learn from those doing it well," said Donlan.