World 100m freestyle swimming champion James Magnussen sent alarm bells ringing in his rivals' ears with an untapered 48.05sec in Adelaide last month - and will aim to peel once more this week at NSW state titles in Sydney, where he is based.

Asked by AAP if his early season form will have caught the eye of opponents, Magnussen said: "To be swimming those times without taper has got to send alarm bells." In Sydney, he hopes to crack 48sec but feels no pressure to meet any specific targets with weeks to go until Olympic trials in Adelaide. 

Neither does he feel pressure from the weight of expectation delivered by a scorching 2011 season in which he claimed the world crown and became the fastest 100m man ever in a textile suit. On expectation, he told AAP: "I quite enjoy it, I don't think it's become a burden at all."

Since victory in Shanghai, Magnussen has paid more attention than ever to diet and recovery, he told reporters. Anything it takes for gold this July: "I am willing to make all the sacrifices necessary to win in London."

In Sydney this week, the world champion, coached by Brant Best, hopes to claim one domestic crown that has alluded him so far: the NSW 100m free title. "I was probably favoured to last year, but my house was broken into (on the day of the event)," said Magnussen, who withdrew from the final a year ago. "It's disappointing that the Queensland and South Australian titles have come before a NSW one, but to add that one to the tally would be nice."

Magnussen will also race the 50m and 200m events in Sydney. On Australia's prospects of adding Olympic gold to their world 4x100m free title from Shanghai last year, he said: "I think we should be pretty strong favourites going into the Olympics with all the guys who were in the team last year still involved," Magnussen said. "This year with younger and older guys making a comeback we're looking pretty good."

The latter included a nod to the likes of Ian Thorpe and Michael Klim, men with towering pasts who must prove themselves all over again in lanes alongside a new generation keen to make their own history.