Michael Phelps is looking forward to finding his top form at the World Championships in Shanghai this week.

The 26-year-old has suffered a number of surprise defeats over the past year, but believes that success in China will stand him in good stead for next year’s Olympics.

"The last few years haven't really been how we've wanted them to be but they were how they were and we have to build from whatever happened and move forward," he said.

"This year I feel like we've made some progress that I think is going to be big for the next year. Hopefully I'm ahead of schedule of where I want to be, but I think this week is a real test.

"I think we're now in the best place we can be with everything that's happened. I feel good in the water and ready to compete, kind of tired of waiting around."

The 16-time gold medallist has said that he will retire from swimming following the 2012 Games.