He's slammed schedule-wise and still makes this work," Rob Kardashian's trainer Gunnar Peterson tells PEOPLE
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Though his public appearances have been rare, Rob Kardashian has recently been hitting the gym.

The reality star has been working out regularly with celebrity trainer Gunnar Peterson.

“Rob is always in!” Peterson tells PEOPLE. “He’s slammed schedule-wise and still makes this work.”

While a source told PEOPLE in March that Kardashian was “depressed and just a bit off in general” after gaining 100 lbs. over the past year, Peterson believes the Keeping Up with the Kardashians star is on a better path.

“Never worry about Rob,” he said.

RELATED: Kris Jenner Wants to Help Rob

Kardashian has also been working out with big sister Kim Kardashian West.

On Tuesday morning she Tweeted, “Rise & Grind! Workout time!!!!! With @robkardashian.” Earlier in the month the siblings went on “the hardest hike ever” together.

Kardashian also shared a photo from his workout on Monday, captioning an Instagram post that shows his sister Kylie Jenner and boyfriend Tyga on a running path, “Spotted these fools on the morning workout.”