Selena Gomez Shows Off Her Toned Stomach in Sports Bra After Biking With Justin Bieber: Pic

Selena Gomez is working on her fitness.

Selena Gomez is working on her fitness.

After going on a bike ride with Justin Bieber on Wednesday in Los Angeles, the 25-year-old singer hit the gym, wearing a black sports bra and matching black running shorts. Gomez draped a towel around her neck and tied her hair back, looking comfy in a pair of white sneakers.

Vasquez-Max Lopes / BACKGRID

Gomez and Bieber -- her on-again, off-again ex -- have been making headlines recently, thanks to the former couple hanging out on multiple occasions after her split from The Weeknd. The two looked affectionate on Wednesday, with the "Wolves" singer at one point resting her head on his shoulder.

A source tells ET that while the two superstars may not officially be dating again, the pair is clearly headed in that direction. According to our source, Gomez and 23-year-old Bieber have been spending all of their free time together, and got back in touch after Gomez underwent kidney surgery over the summer. 

“This shouldn’t even be considered ‘getting back together’ -- it’s really a brand new relationship," the source says of where the two stars stand now. "They are both different people and their relationship now is completely different."

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