The star has been dating the model for several weeks

Updated January 28, 2016 07:00 PM
Source: Rob Kardashian/Instagram

brightcove.createExperiences(); Rob Kardashian is working up a sweat.

On Thursday, the Keeping up with the Kardashians star shared a photo on Instagram of himself hitting the gym. The post comes days after news broke that Kardashian is dating Blac Chyna. The pair were spotted driving to his mom Kris Jenner‘s Calabasas home Wednesday.

Kardashian, 28, has shied away from the spotlight for the past two years as he has struggled with depression, significant weight gain and a health scare that saw him hospitalized and diagnosed with diabetes. In August, Kardashian posted a workout selfie and his trainer Gunnar Peterson told PEOPLE at the time the star was committed to fitness.

A source confirmed to PEOPLE on Monday that Rob and Blac Chyna, 27, “are dating and have been for a few weeks.” While it’s unclear “how serious” the relationship is, the source said that the pair bonded over their “anger toward the [Kardashian-Jenner] girls.”

“Rob has been lonely for so long, so of course it’s great for him to spend time with someone other than his sisters,” the source said. “Rob likes her and seems to think it’s mutual.”

Black Chyna was once close friends with Rob’s sister Kim Kardashian West. That friendship ended when Blac Chyna’s ex-fiancé Tyga, with whom she shares a son, began dating Kylie Jenner.