Britain's Olympic great Chris Hoy announces retirement

Britain's most successful Olympian, Chris Hoy, on Thursday announced his retirement from cycling with immediate effect, prompting glowing tributes from leading figures in the sport.

British Cycling performance director Dave Brailsford, who oversaw the 37-year-old Scot's transformation from BMX rider to a ruthless track sprinter who won six Olympic golds, as an icon.

"I can't speak highly enough of Chris and his career," said Brailsford, who, like Hoy, was knighted by Queen Elizabeth II following the British team's exploits in London.

"Chris' application, athleticism and dedication are second to none and I've said it many times, but he is a true Olympic champion who embodies all of the Olympic values."

Hoy made his announcement -- which had been widely expected -- at Murrayfield stadium in his native Edinburgh.

"I'm officially announcing my retirement from international cycling," he told a press conference.

"It's a decision which I didn't take lightly. It's something I thought about hard with the help of my family and my coaches."

Hoy overtook rower Steve Redgrave as Britain's most successful Olympian at last year's Games in London, when he claimed gold medals in the team sprint and the keirin.

He had hoped to continue competing until next year's Commonwealth Games in Glasgow, where the cycling event will be held at the Sir Chris Hoy Velodrome, but said he was no longer capable of competing at the highest level.

"I've got every last inch of energy and effort out of me," he said.

"I went to London and was successful but I didn't realise quite how much London took out of me. To go on for another year would be one year too far. I don't want to turn up just to wave to fans and get a tracksuit.

"I wanted to compete and get a medal for Scotland and because I didn't think I could do that, I wanted someone else to take my place."

Asked to select his career highlight, Hoy singled out his first Olympic gold medal, in the 1km track time-trial in Athens in 2004, and his last, in the keirin at last year's London Games.

"Athens -- stepping onto the podium, hearing my name read out and then hearing 'Olympic champion' after it. To me, that was what my career was all about," he said.

"I thought nothing could compare to that but in London, to end my career with my sixth gold medal in the nature of the keirin, was a really special moment.

"But I could go on all day. I'm fortunate I've got so many great memories and I've had so much fun. I still feel the same. I'm going to cycle for the rest of my life and encourage others to take up the sport."

British sprint sensation Mark Cavendish, who has won 23 Tour de France stages, said Hoy's impact on cycling could not be overstated, as he spearheaded the country's dominance of the sport in recent years.

"He's one of the most professional athletes I've ever seen, one of the nicest men, on and off the bike, that I've ever met," Cavendish said.

"What he's done for cycling for this country has been bigger than anybody can even put into words."

Hoy is an ambassador for the Commonwealth Games in Glasgow and has also announced plans to launch his own brand of bicycles.