The Australian rugby league squad were also using the facility after their win over Great Britain on Saturday.
He made jokes and admitted he had become accustomed to the pressures of Premiership life.
"I'm used to it,'' Viduka told the Australian Associated Press.
"It's part of the game. Last year we were under a lot of pressure as well and we're under it again.
"Pressure-wise I'm used to it. It's life, it's football life over here. Nobody pays you nothing for nothing.''
When asked whether he was enjoying life at Leeds, Viduka laughed and said: "At the moment I'm rapt here, I'm happy.''