Nick Jonas bulked up big time through boxing, and shares his tips — and shows off his rock-hard abs

Credit: Peter Yang

When Nick Jonas heard about the TV show Kingdom, he wanted in. But no one on the show believed the singer and former boy band member was ready to take on the role of a MMA fighter — let alone act.

Jonas was determined though, and eventually won the part, but then the hard work of getting in fighter shape started.

“I put on about 20 lbs. of muscle in a month and a half,” he tells Men’s Fitness. “It was wild. But it was also hard to sleep. I was carrying more weight than I was used to, so I was sleeping very hard.”

Jonas focused on lifting in the months leading up to filming, and then switched to two workouts a day, five days a week. Plus, he went from eating 3,000 calories a day to a whopping 4,200.

Jonas worked out in a small, private gym with owner Gregg Miele, and only focused on his own progress, to avoid comparing himself to anyone else.

Nick Jonas
| Credit: Peter Yang

“It’s important to stay in your lane,” he says. “One philosophy Gregg teaches that I really appreciate is that everybody’s got a different approach to fitness. No one way is wrong. Being competitive is good, but it can also leave you sore and struggling to recover. Your body feeds off that recovery time, so don’t push yourself so hard just to do better than the guy next to you in the gym.”

Jonas also had to worry about keeping his type-1 diabetes in check while he was training at extreme levels, and had blood work done to find a diet that would work. It taught him how to pick good foods.

“When I’m on the road, I always make healthy choices,” Jonas says. “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.”

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And while he now has abs that make women swoon, Jonas says he’s keeping dating on the back burner for now.

“Well, I think love and romance happen for some people, and it’s an amazing thing. But right now I’m really serious about my work,” he says. “I’ve got too much on the agenda to really think about losing myself to love.”