World 100m freestyle champion James Magnussen, whose 47.10 blast at Australian Olympic trials last month, rocketed him a league ahead of peers as the fastest sprinter ever in a textile suit, has pulled out of a national-team training camp after suffering another chest infection.

Magnussen had glandular fever on the way to success at world titles and had chest-related problems on the way to trials but illness did not prevent him from racing into uncharted waters. 

Head coach to the Dolphins Leigh Nugent, who will lead the camp in Canberra, told reports Down Under: "James has got a bit of a lung infection and he's had a bit of a problem with that before, but he's OK. We all have some physical weakness in our make-up and when you're a bit stressed, it usually manifests in that area James's just seems to be his chest.

"So it does seem to be an area of weakness for him. But you can have short periods of illness and that's pretty normal for a high-performing athlete. It's just part and parcel of the process."

The three-day camp at AIS headquarters in Canberra will target relay takeovers, starts and turns, the alchemy of converting 4th to bronze, bronze to silver and all things to gold king in the equation.

Magnussen will stay at his Sydney base on a light programme designed to aid his recovery.