KCSPresse / Splash News 1 / 8
KCSPresse / Splash News 1 / 8

By Melissa Hunter

This week I had the opportunity to do a workout session with trainer to the stars Harley Pasternak at the smartwater Malibu beach house. Four days later, I think I'm finally not sore. Was this just a ploy for my bosses to get me in shape?

Harley's 5-Factor Diet has been a celebrity favorite for quite some time, and his client list includes Miley Cyrus, Robert Pattinson, Lady Gaga, Megan Fox, Katy Perry, Seth Rogen, and the Jennifer Hudson who recently had an incredibly impressive body transformation. I got a chance to chat with Harley about Hudson's story, his philosophy on exercise and why he discourages his clients from getting too skinny.

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Why his diet appeals to the celeb clientele:

"It requires the least amount of time for the most amount of results, and the clients that we have, that's what they're looking for. They need to see results, and they don't have a lot of time to see those results. It also has to be sustainable."

On Jennifer Hudson's impressive body makeover:

"We got hired to help her prepare for the film she's shooting right now, to play the role of Winnie Mandela … She's not someone who typically liked exercising, but she saw the results and we got her working out 5 days a week and she had a newborn at home so I got her taking walks with her baby in the area she lived in ... She was fantastic to work with and she still is. She's in South Africa right now shooting and we email on a regular basis to find out what workout she's doing and how much cardio she's doing."

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How he got Robert Pattinson to be even more swoon-worthy:

"We work with him whenever he has a film to get ready for, which is quite often. Right now for the movie he's doing, 'Water for Elephants,' we're working with him on that. He's a great client, works hard. Again, not someone who naturally is someone who grew up working out and going to the gym, but it's part of his job and part of looking good and feeling good."

On the difference between young clients like Miley and older ones like Jane Fonda:

"Age today is very different than age used to be ... We have some of our oldest clients that are actually our fittest clients. People I've worked with like Jane Fonda, like Jeff Goldblum, who's almost 60, these people are fitter than anyone in their 20s that we work with."

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Why scary skinny starlets aren't thinking ahead:

"If you're emaciated skinny, you don't feel great. There are compromises and sacrifices. Women should look like women. Women need natural curves, and women if they're too lean, their hormonal cycle gets thrown off and they stop looking and feeling like women. It's really been important to me that a man should look like a man, a woman should look like a woman, and you should feel great and never feel like 'Oh gosh, I don't know how long I can keep this up for.'"