Vitali Klitschko has played down concerns about his age ahead of his WBC heavyweight title defence against Britain's Dereck Chisora next month.
The Ukrainian fighter, who turned 40 last July, is the second-oldest boxer ever to hold a world heavyweight title behind American George Foreman, who was 45 when he was triumphant against Michael Moorer.
"I'm 40 but I feel 25. I am in great condition, great form and have great experience," Klitschko said.
The fight will take place in Germany on Saturday, February 6.