(LOS ANGELES) -- Rob Kardashian hasn't been in the public eye for quite some time. On Keeping Up with the Kardashians, cameras documented how the reality star struggled with depression and later weight gain, reportedly packing on over 100 pounds.
But now Kardashian's back in the gym, and recently joked about his reported ongoing efforts to shed a few extra pounds. "Started right here with these milkshakes hahaha," he wrote on Instagram, next to a throwback Thursday photo of him enjoying desert.
Rob's sister, Kim, also bragged about his workout efforts. Earlier this week, she tweeted, "Rise & Grind! Workout time!!!!! With @robkardashian." Earlier in the month, the siblings went on what Kim called "the hardest hike ever" together.
Kardashian's trainer, Gunnar Peterson, told People magazine earlier in the week that Rob's been hitting the gym hard. "Rob is always in! He's slammed schedule-wise and still makes this work," Gunnar said. "Never worry about Rob."
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