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Staying in shaping isn't easy -- just ask Teen Wolf actor Colton Haynes!

At the "Cybergeddon" premiere in West Hollywood, Calif. on Sep. 24, the former male model, 24, admitted he's not as burly as he was while filming the MTV series' second season just a few months ago. "I just lost 16 pounds of muscle, but I'll get it back -- it's easy!" Haynes told Us Weekly. "It's so hard to keep it on."

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Haynes explained that he works with "amazing trainers" to sculpt his bulging biceps and perfect pecs. "I haven't had [a session] in a while, which is why I dropped a little weight, but I'm a huge fan of yoga and spin class," the actor said. "Spin class is the best for your core!"

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Of course, exercise isn't enough to keep Haynes' body in mint condition. "Unfortunately, diet is 75 or 80 percent of trying to get in shape, so you do have to try to cut the carbs," he told Us. "The diet's a huge part! I'm from Kansas, so I love ranch dressing and McDonald's. When I'm working, I have to stay away from all that!"

Luckily, eating healthy hasn't interfered with the single actor's love life. "The good thing is when you're going on dates, you want to go to a nice place, so they're [probably] serving chicken and steaks," he explained. "You can eat them with vegetables, so you're good."

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Though Haynes was recently (and falsely) linked to "Pretty Little Liars" actress Lucy Hale, 23, the hunky star admitted Chris Zylka's ex "is such a special girl in my life." As for what he desires in a significant other, Haynes revealed he's looking for "someone who just wants to have fun and isn't afraid to go out in jeans and a hoodie and just hang out."


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