Justin Bieber Shirtless: Singer Tweets Photo Of His Six-Pack At The Gym

Justin Bieber posts shirtless photo of himself on Twitter.

Now that Justin Bieber is single (well, sort of), the 18-year-old is trying to bulk up for his lady fans.

The singer, who has been on again-off again with his girlfriend of two years Selena Gomez, 20, posted a shirtless photo of himself on Twitter, writing, "Back in the gym."

"good workout. #focused," he added on Nov. 23.

Bieber flaunted his trademark tattoos, including his new owl ink, while showing off his hard work. According to the Daily Mail, the teen recently told Macleans that he's trying to get in better shape.

"Ive b! een working out in the gym, getting bigger," Bieber revealed, "trying to get sexy for the ladies."

Bieber has been spending time with his family this week in Canada, tweeting a picture of his step-siblings Jazmyn, 5, and Jaxon, 3.

"random - i love being a big brother," he tweeted.

See a photo of shirtless Justin below:

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