Nick Jonas Looks Seriously Ripped in Arm-Baring Workout Photo

Whatever Nick Jonas is doing in the gym is clearly paying off!

The singer-turned-actor, 24, wears a muscle tank that shows off his incredibly toned arms in an Instagram photo he shared on Thursday.

“Gettin it today,” he captioned the pic, taken in what appears to be a boxing gym. “Two a days in prep for Kingdom season 3.”

Jonas told Men’s Fitness last month that he “put on about 20 lbs. of muscle in a month and a half” as part of his prep for the show, in which he plays an MMA fighter.

He focused on lifting in the months leading up to filming, and started doing two workouts a day, five days a week.

Jonas also went from eating 3,000 calories a day to 4,200, but always makes sure that what he’s eating is healthy.

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“When I’m on the road, I always make healthy choices,” he told the magazine. “I don’t have a meal plan delivered to me, but I know what not to eat. I’m always cautious about the food I put in my body.”