Celeb Trainer Gunnar Peterson Spills on How to Get a Celeb-Like Bod

WW: How do you get a booty like Kim's?

GP: Well, you have to make sure you are consistent with the workouts. You have to make sure you make good food choices outside of the gym. I don't ask you to be perfect -- nobody's perfect -- but make good choices overall, and you'll see results a lot faster.

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WW: We recently spoke to Vanessa Lachey, who said she's working out with you through her pregnancy. How have you altered her workout to accommodate for the baby?

GP: Well, you have to remember that when you are pregnant -- don't take this personally -- it's not about you right now. It's about the fetus. You're automatically a silver medalist, so you have to bear in mind what can the body take, what's healthier for the baby, and so you push the person, but this is not about trying to get you in a certain pair of jeans or trying to get you ready for a certain ball gown. This is about getting you ready to have as comfortable pregnancy and birthing experience as possible, getting it so when you do fire up your comeback post-baby, you're not starting so far behind the ball that it's ominous.

WW: How many days a week do these women workout?

GP: Depends on the person. Some of them are two times a week, but then they do two things outside of your week. Then some of them are six days a week and won't go anyplace else but here. And it depends on the person at that time -- some of them are two times a week for a while, then they bump up then they bump down; some are always all the time. It just depends.

WW: So you don't necessarily have to work out every day?

GP: No, but you do have to do something for your body every day. It doesn't have to be fire and brimstones, personal records every time, but it is to challenge yourself.

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WW: Why do you think celebrities are drawn to your method of training?

GP: I think they're just drawn to my gym because I have paparazzi-free parking. You can pull in and it's my parking lot, so they can't come in. That's a major deal! I think this. One, I try to be the one constant in their lives. The gym looks the same, feels the same, smells the same. It's like if you check into a Four Seasons, you always know you're going to get this level of service; the room is going to be this size. I try to appeal to them. I'm all for getting down and dirty in the workout, but I don't think there needs to be gum wrappers on the floor to make it a spit-in-the-corner kind of gym -- that's not what I'm doing. I try to provide a constant, something they can rely on. I just had a client, a pop star girl, that was in China for two days that was doing a private appearance, and she calls me and goes, "What do I eat? Because all the stuff isn't on the nutrition list," and I go, "No problem. Take a breath. Read me the menu. Here's what we do, and here's what we don't do," and we go down it. It was an eight-minute call, and it changed her trip.