Before you began acting, you were a model. What about Calvin Klein underwear made you want to go back to modeling again?

I got into modeling because I was in a financial crisis. It was a great way to make money. I never thought I was pretty by any means. But it was great to be a part of that world. And the pinnacle of that world
is to be on a billboard. I grew up wearing Calvin Klein. As a model, I
dreamt of being Marky Mark, being on a billboard, and selling that
company.

Speaking of Marky Mark, were you nervous about comparisons when shooting this campaign?

I was thrilled. I loved Marky-Mark’s campaign. And by no means was I trying to fill his britches or, uh, boxer-briefs. I was just stepping into them and doing my best to follow his footsteps. And that’s all I
can hope and pray for. I think the audience has really enjoyed the
campaign, so it’s nice to be a part of it.

Any surprises in store for the next “Twilight” movie, “Eclipse”?

It’s really tough for our characters — the movies are based on the books. So a lot of characters are like — they barely have lines, they’re barely in it. But you can’t rewrite the books. I’m just
grateful to have a line or a purpose in there. But definitely, Emmett’s
character and story grow immensely in “Eclipse.” You see the battle
between the [vampire] newborns and you see the werewolves coming along.
It’s a big fighting movie and that’s Emmett’s strength. So there’s the
fighting and the big brother role, which is nice.

Since you were already in production, did you really have to prepare physically for this Calvin Klein campaign?

Well, I did. You know Emmett, my character, is more of the big guy. So I don’t need the washboard abs, just the size. I did a lot of push-ups and tons of protein. But for Calvin Klein, it’s underwear. So I
called up my buddy Rich McDonald, who’s a personal trainer friend of
mine. He put me on a great diet that took out the candy (which I love)
and the carbs past 4 o’clock (which I break here and there). And he told
me a great thing, which is to drink water as much as you can. ’Cause
when you don’t drink water, your body needs to hold on to it to stay
hydrated. So I started training with him and he got me into the shape
that I need to be for the campaign. I trained for two weeks.

Have you seen the line of fans waiting outside for you?

No, I didn’t actually. But I love the fans. We in the “Twilight” franchise have the best fans. And it’s really cool to see them come out to something other than “Twilight,” you know? ’Cause then it feels more
personal. Then they’re Kellan’s fans.

On his own undies ...So … boxers or briefs?

Boxer-briefs! And I love the blue trimmed ones. The blue ones bring out my eyes. [Laughs.] I didn’t come up with that. I was on the street and I bent over to pick up my bag out of the car and this girl yelled
out, “You have the blue ones on and your eyes are blue.” And I was like,
“Oh yeah, they do bring out my eyes!”

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