Triple Olympic champion Stephanie Rice is not 100 per cent ready for the world swimming championships and isn't confident she will win gold - but still expects to break her own world records at the Foro Italico.

The twisted conundrum facing Rice has been brought about by her recent health issues and the new swimsuit generation that will leave a question mark over every time posted in Rome.

Rice has battled a respiratory problem in the past week and while she says she is about "97 per cent" healthy right now, she hopes to be fully healed for her 200m individual medley heats when competition starts on Sunday.

She will wear the full polyurethane Jaked suit for the shorter event, but is still deciding whether to stick to the Speedo LZR for the 400m IM later in the meet.

"I definitely think it will take a world record in both the IMs to win," said Rice on Thursday.

"I'm very interested to see how quick the times are this year and hopefully I can be up there in the mix.

"Obviously a world championship is something that is a huge goal of mine and I would love to be there at some point in time. (But) I'm not sure if this is the year or in the future.

"I wanted to come into this meet being as best prepared as possible but at the same time I'm not as prepared as I was last year.

"Right now it's just a mental game but I know that racing is always a mental game."

Rice deliberately avoided signing a contract with any swimwear manufacturer this year so she could be free to make her own choice at these titles. The decision may have cost her thousands of dollars, but it won't leave her "handicapped" on the blocks.

Libby Trickett has chosen to stay loyal to Speedo this meet and says her recent times in the LZR were faster than when she tested a Jaked suit.

But Andrew Lauterstein insists the LZR is inferior and has opted to wear Jaked in Rome, possibly risking his contract with Speedo with negotiations between his management and sponsor ongoing.

Rice too is amazed at the Jaked difference. She wore the suit for a broken 400m medley time trial in training and was two seconds faster per 50m lap than when she wears her normal swim costumes. She doesn't know how these times compare to the LZR suit, but it was enough to convince her to wear a suit with a zipper back for the first time in her career.

"The times I did in training were insane, amazing to be going those times and a huge confidence boost," said Rice.

"Obviously that is what my choice came down to, knowing I could hold those times a lot faster than I've ever swum before.

"I don't want someone to stand next to me in a suit I know was quick and not have that advantage, mentally I know it would hinder my performance."

Todd Balym
AAP