Justin Bieber Bares Naked Butt On Twitter: His Diet and Workout Routine

justin bieber naked butt — A naked Justin Bieber showed off his bare butt on Instagram, to the delight of his millions of followers.

Justin Bieber delighted his legions of fans July 7 by posting a nude photo on Instagram and Twitter that showcased his bare butt.

In the photo, Bieber stands naked on edge of a boat while pointing at some gorgeous scenery. “Look!” Justin wrote in the caption.

It’s evident from the photo that Bieber, 21, has filled out and gained some muscle weight during the past few years.

In January, Justin showed off his rippling six-packs in sizzling ads for Calvin Klein Underwear and Jeans.

Justin Bieber showcased his ripped physique in sizzling ad photos for Calvin Klein jeans and underwear.

In the photos, a jacked-up Bieber models shirtless in Calvin Klein Jeans and Calvin Klein Underwear.

The once-scrawny Justin has chronicled his physical transformation during the past year with regular Instagram photo updates that show him morphing from a skinny teen into a buff young man.

Bieber regularly posts photos of himself pumping iron at the gym. Justin has filled out from years past, when the lanky Canadian pop star weighed a mere 108 pounds.

Justin said he has been lifting weights seriously for the past two years in a bid to bulk up.

Justin Bieber works out5 days a week to stay buff. — Justin Bieber works out five days a week to stay buff.

“I’ve been working out in the gym, getting bigger, trying to get sexy for the ladies,” Bieber said on Twitter.

Justin previously trained with “The Biggest Loser” star Dolvett Quince, author of the bestseller, The 3-1-2-1 Diet. Quince stopped working with Bieber when he joined “The Biggest Loser” in 2011.

Justin’s current trainer, Patrick Nilsson, said Bieber typically trains 40 minutes each day, five days a week, mostly lifting weights and focusing on building up his chest and shoulders, Examiner reported.

justin bieber abs workout routine — Justin Bieber, who once weighed 108 pounds, has bulked up during the past few years.

“I work out with my trainer, Patrick Nilsson, five days a week for about 45 minutes each,” Bieber said 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.”

Justin doesn’t follow a special diet, and Nilsson said the focus is on making sure the singer consumes enough calories since he sometimes forgets to eat due to his busy schedule.

“I’m not a special diet, but I do try to watch what I eat,” said Bieber. “I do eat unhealthy sometimes!” Justin released his third studio album, Believe, in 2012.