Khloe Kardashian's Personal Trainer Says She's an 'Animal'

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"Khloe's an animal," says celebrity trainer Gunnar Peterson of the 31-year-old Kardashian sister, who made headlines recently for her Complex cover shoot, and has been getting into impressive shape through waist training and most importantly, intense workouts. "No complaining, no bitching, just gets after it."

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Peterson has trained most of the Kardashians/Jenner clan, including Khloe's sisters Kim and Kourtney as well as mom Kris, who posted a photo last week for Gunnar’s birthday, thanking the trainer for "whipping my whole family into shape!"

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The in-demand personal trainer has worked with some of Hollywood’s hottest stars including Kellan Lutz, who calls the workout guru "awesome" and "innovative." Peterson did admit however, that some stars, like Sofia Vergara, are just like us when it comes to working out.

"Her favorite thing to do at the gym is leave," Peterson laughs.

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ET’s Brooke Anderson joined the fitness expert for a workout similar to the one’s he’s given Khloe on episodes of Keeping Up With the Kardashians. Peterson says the reality star’s dedication to exercise and a healthier lifestyle are already paying off in a big way.

"You can see it," he said. "The changes she's made are incredible. She's done it the right way. Nothing fast. Hard work."

The sought-after trainer even spilled some of his secrets to ET.

"Couple strength training with cardio," Peterson recommends. "So many people jump to straight cardio. If you’re on a bike or running for 25 minutes, drop down every five minutes and do ten squats, ten pushups and ten crunches."

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