Heidi Montag lives her life on camera as the star of the hit reality show The Hills. But she's getting a whole new level of exposure in the September issue of Playboy, which hits newsstands on Aug. 14. Life & Style joined the 22-year-old during her beach workout in Malibu on Aug. 3 to get all the bootylicious details. "I'm not wearing anything in the Playboy pictures," Heidi tells Life & Style. "My skin is my accessory."

L&S: Why pose for Playboy?
HEIDI: I'd been thinking about it for a while. Playboy's such an iconic magazine. Plus, I'm getting older, and I'm married [to The Hills co-star Spencer Pratt], so I'm tapped into a whole different sexuality. I thought it would be fun to express that in my first racy photo shoot.

L&S: How did your workout change before the shoot?
HEIDI: I used to go on the treadmill and have a more casual workout. Now I have a routine, and I work out five days a week for an hour every day. It's more of an athlete's training.

L&S: What's your favorite move?
HEIDI: The dead lift. I lift 100 pounds, and that's pretty much my weight. It's very empowering. I feel more comfortable and confident alone. I don't need my husband to carry my luggage downstairs -- I can do it. I feel pretty buff.

L&S: Did you lose weight in addition to adding curves?
HEIDI: If anything, I gained a little because I got more muscle. I toned up, I firmed up, and this booty probably weighs 5 extra pounds.

L&S: So Spencer likes you curvaceous?
HEIDI: He loves my new additions. I just want to be the foxiest wife.

For more on Heidi's Playboy body and new workout regimen, pick up the latest issue of Life & Style, on newsstands now!

Photo Credit: Brad Swonetz