Vitali Klitschko has said that reaching 40 provides no concern for when he fights Tomasz Adamek on Saturday.
The Ukranian is defending his WBC Heavyweight title in Wraclow against the 34-year-old Pole.
"If you remind me about my age, I think 'Wow! Forty years old... wow!'" the elder Klitschko brother said.
"But you know what? All my sparring partners in my training camp - and there were five of them - were under 30. And I was in better condition."
Vitali's brother Wladimir defeated Britain's David Haye in July and Vitali has said opponent Adamek is better than the Englishman.
"After my brother Wladimir and me, Adamek is the third best heavyweight in the world," he added.
"He is definitely better than David Haye who is just a world champion in talking."
