NEWCASTLE Knights coach Brian Smith has ordered skipper Kurt Gidley to err on the side of caution as he recovers from knee surgery.

Newcastle's No.1 game-breaker required extensive repairs to a torn cartilage he suffered during the first match of Australia's World Cup campaign.

Two months on, Gidley has resumed light training but Smith does not want the 26-year-old to over-exert himself until the injury was 100 per cent healed.

"We're taking a softly, softly approach with Kurt," Smith said.

"The damage in his knee was worse than they initially expected, and we want to make sure he doesn't push himself too hard too soon. He's started some light running and he's still working out really well in the gym.

"At this stage of his career, he doesn't need to develop himself like a lot of younger players do.

"He needs to maintain himself, and we don't want him to do anything at all that might make him sore and set him back."

Regarded as one of the fittest players in the NRL, Gidley said it was frustrating that he had been unable to join his teammates in training sessions. He has still been putting in the hard yards in the gymnasium and pool.

"It's worse being in rehab than training with the team," he said.

"It's frustrating enough just watching the boys train and not being able to run around.

"But because of that I have to keep up the cardio side of things, which means using the bike and glider and swimming - all the not-so-exciting stuff.

"It's longer days, I'm afraid.

"You've got to make sure you watch the rest of the team, to take in whatever they're doing … new plays or wrestling techniques and that sort of thing.

"So I have to take in what the rest of the boys are doing, then sort out my own fitness work and then also get my physio done.

"But that's all part of coming back from an injury, I suppose."