Justin Bieber and Calvin Klein nearly broke the Internet on Tuesday, Jan. 6, when he was revealed to be the hot new underwear model for the brand's iconic #MyCalvins campaign. The pop superstar, 20, was forced to stay mum about his hot ab-baring shoot with Dutch model Lara Stone for months — and now that the secret is out, he tells all to Us Weekly. In a new exclusive photo, Bieber displays his underwear in low-slung denim jeans, while revealing his fit body.
"I've wanted to be involved with Calvin Klein for a while now," the "Believe" singer explains. "Earlier this year, I put up a picture on Instagram of me in their boxer briefs with the #mycalvins tag, and people went crazy for it and it got their attention."
The top-secret shoot took more than two days to complete. "It was actually two-and-a half because I got sick during the second day," Bieber tells Us. "Behind the scenes, everything ran like clockwork — we'd come in, do glam, and get right to shooting."
Although the campaign was kept under wraps, Bieber and his co-model snuck in a few hints before it was officially released. "It was hard to keep things under wraps," Bieber admits. "The Fashion Rocks presentation was definitely a clue, and I wasn't worried about the negative reaction from the crowd when it happened," he says of the 2014 strip down that incited boos from the audience.
As for those awe-inspiring abs and pecs? "I work out with my trainer, Patrick Nilsson, five days a week for about 45 minutes each," he reveals of his fitness routine. "We do three days splits: back and triceps one day, chest and biceps on day two, shoulder and legs on day three, and abs every other day."
Amazingly enough, the Biebs didn't have to subject himself to an extreme diet to prep his bod for the shoot — in fact, junk food remained on the menu! "I'm not a special diet, but I do try to watch what I eat," he says. "I do eat unhealthy sometimes — I am a 20-year-old guy!”
For more on Bieber’s sizzling ad campaign, pick up the new issue of Us Weekly.