Olympic coxless fours champion James Cracknell says he hopes he will return tougher from his year out of rowing.
Cracknell should be back for Beijing
The 32-year-old Briton announced he was taking a break from the sport but is expected to return to action after next year's world championships.
"I'm planning to compete in both the London Marathon and the London Triathlon and some other sporting events over the year," he told the BBC.
"Hopefully I will learn from them and come back mentally sharper."
Cracknell won coxless fours gold at the Athens Games by the narrowest of margins with team-mates Matthew Pinsent, Ed Coode and Steve Williams.
His announcement comes as a major blow for British rowing, with four-time Olympic champion Pinsent expected to confirm his retirement on Tuesday.
Cracknell admitted that returning to tough training after Olympic glory was difficult.
"Although I started training again soon after Athens, over the last year, I used up a lot of energy and motivation.
"After training full-time for 12 years, I felt I needed a break," he said.
"The appeal of training for five hours a day just isn't there as it was after Sydney four years ago.
"It's not fair to my coach, my team-mates or myself if I am not at the right level both physically and mentally."
As well as training for the London Marathon, Cracknell is planning to use the winter to work with Alex Partridge who is back in training after missing the Olympics with a punctured lung.