Heidi Northcott and Chuck Liddell Workout Video: Naked? Yes. Stalker? No.

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NEW YORK (CBS) The video is shaky. The viewer can hear the cameraman breathing and fumbling with the camera. It looks like it was shot on a camcorder through a window. It's UFC champion Chuck Liddell and his bombshell girlfriend Heidi Northcott working out in what looks like the privacy of their home gym. And they're both naked. It ends after 42 seconds; the last shot is a leering tilt up and down Northcott's body.

PICTURES: Heidi Northcott

What is this? An egregious violation of two semi-celebrities' privacy? A video taken by a stalker?

Nope. It's an ad. The viral kind. Correction: the successful kind.

Photo: Heidi Northcott

PICTURES: Heidi Northcott

If one can tear one's eyes away from all that naked, one will notice that Chuck and Heidi aren't totally nude. They're wearing shoes. The same shoes Chuck shills in a sponsorship deal with Reebok.

Despite early reports that wondered if a peeping tom or paparazzi had snapped the video illicitly, TMZ confirms that the duo was in on it.

The video may be viewed here for those who don't find the above photos revealing enough.

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