Prime Minister Vladimir Putin has revealed his fitness secrets to supermodel Naomi Campbell and told her that he likes martial arts matches, admires girls who posed in their underwear for him, and doesn't feel particularly tough.

Putin handled a slew of casual questions from Campbell during the St. Petersburg Tiger Forum in November, and the interview was published by British GQ magazine late Monday.

Campbell, who has a Russian boyfriend, businessman Vladimir Doronin, praised Putin's physical shape during the interview, a transcript of which is available on the government web site.

Putin, 58, said he goes to the gym and swims every day in addition to occasionally sparring with friends on the judo mat.

Campbell said she was amazed that the butterfly stroke is popular among Russians and mentioned a picture of Putin swimming this way in a Siberian river in 2009.

“I was swimming the butterfly stroke because the water was cold,” at about 16 degrees Celsius, Putin said. “My idea was to get out of the water as soon as possible."

Putin praised the courage of journalism students at Moscow State University who posed in their underwear for an erotic calendar for his birthday last fall.

"I liked the girls, they're beautiful," Putin said.

He said they were “courageous” because they knew they would be criticized by classmates for “flirting with power.”

He had less to say about another group of fully dressed students who later shot a calendar with critical questions to Putin. “It's fashionable to criticize people in power,” Putin said about them.

When asked about his impressions of his summer ride with bikers in Crimea, Putin said, “I'm not the tough guy, those guys are.”

Campbell said Putin has a habit of attending bare-knuckle fights and asked whether he ever participated himself. Putin said he sticks to judo but called the sport “deserving respect” — female fights included.

Alexei Mukhin, an analyst with the Center for Political Information, said the interview appeared to send a message to the West that Putin remains strong politically. “With the interview, he is telling the West, 'I'm in a good political shape,'” Mukhin said by telephone.

Putin's spokesman couldn't be reached to comment late Tuesday.

GQ raised eyebrows in 2009 when it published a report in its U.S. edition about the 1999 Russian apartment bombings that a magazine lawyer referred to as "Vladimir Putin's Dark Rise to Power" — and then barred the issue from being distributed in Russia and the article from being posted online or in any of its foreign editions.

Campbell also interviewed Venezuelan President Hugo Chavez for GQ last year.

At the St. Petersburg tiger forum, Putin also met with movie star Leonardo DiCaprio, whom he called “a real man.”