Usain Bolt sat out of Jamaica's open training session but team manager Ludlow Watts has insisted that the sprinter will be fit for the Olympics.

There have been doubts regarding Bolt's participation in London following a back problem.

However, Watts said that he is "not aware" of any injuries that the 25-year-old may be carrying.

"Let me say, by the time he gets to the Olympics he will be competition fit," said Watts. "By August 4 we will see the real Usain Bolt.

"I'm not aware of any niggles at the moment. I believe he is okay."

Bolt won gold in the 100m and 200m events in Beijing.