Kiefer Sutherland is amazed he is still alive.

The '24' actor - who plays government agent Jack Bauer in the US drama series - admits he finds doing his own stunts increasingly difficult, but always gets involved with as much of the action as he can.

He said: "It's amazing that I'm still alive. Jack Bauer's taken an a*s-kicking, that's for sure. It's kind of in keeping with the character that he's taken as much as he's dished out.

"But you can't fake the physical side of it. If you're hanging underneath a garbage truck going 45 miles an hour, you're not going to be faking your fear. You jump off the side of a building, you're gonna react the way you should.

"Some of the stunts I can still barely do, but I've loved doing them."

The 43-year-old star also revealed he is mystified by the way the public respond to him, particularly if they see him at airports.

He explained to Parade.com: "I get in the same line as everybody else and go through the same search as everybody else. They probably talk to me a little more than the other passengers, but that's about it.

"I've always been shocked that people that I'm actually flying with say, 'Oh, I feel safer on the plane with you.' I'm thinking, 'You must not watch the show because everybody around me gets killed.' "