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'Survivor' Ashley Underwood says starvation diet took her down to 108 pounds

Photo Credit: Tessa Johnson

Fans of the CBS reality hit “Survivor” know that after living on a diet foraged from the wilds of some remote tropical locale, the women come back from their ordeal ripped and lean—really, REALLY lean.

“I lost the most out of any of the girls—20 lbs. in 38 days,” Ashley Underwood, the third runner-up on “Survivor: Redemption Island,” tells FOX411.com exclusively. “I weighed something crazy like 108 lbs. when I got back. I’m 5’8”, so can you imagine? I didn’t leave the house for a month because I couldn’t come to terms with how I looked!”

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Underwood, who is a fitness expert and former professional basketball player, had a hard time getting back to her ideal weight of 125 lbs.

“I was really sick when I got home—I was in the hospital because I had a parasite,” explains Underwood. “I couldn’t put the weight back on right away, because I couldn’t hold food down.”

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While in Nicaragua, the former Miss Maine lived on a meager diet, “We ate one thing, and that was rice. I mean, we would eat a handful of rice in the morning and a handful of rice at night—and that was it. That was our ration.”

Despite working at grueling tasks all day and eating next to nothing, Underwood wasn’t overly hungry. “It’s so bizarre—obviously, there are times that are worse than others, but your body adapts,” she says. “You get accustomed to it.”

While competing on reality show in the jungle may not be the easiest—or most practical—method to lose weight (“I wouldn’t recommend it as a way to get bikini ready for the summer,” laughs Underwood), but there are a few “Survivor” tips that can be adapted for use back home.

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“I drink tons of water,” says Underwood. “On the show, I would drink as much water as I could to try and combat the hunger pangs, but water is great—as soon as I wake up in the morning, I hydrate, even if I’m not thirsty, I force myself to drink water throughout the day. It cleanses your body, it keeps your metabolism going, it’s just good for you. I don’t drink soda, I don’t drink coffee—and I think that has a lot to do with how I stay in shape.”

And to get fit without the benefit of “Survivor” host Jeff Probst cracking the whip, Underwood recommends keeping a schedule. “The biggest thing with exercising is just to make the time,” she says. “A lot of people make excuses, ‘Oh, I don’t have the time,’ but even if you can sneak in thirty minutes a day, it will really help get that heart rate going—do walking lunges, jump roping, push-ups—those things you can do at home, even if you don’t have time to get to the gym.”

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While Probst may have had Underwood sweating in the challenges, he got her flushed in other ways, “I have a huge crush of Jeff—it’s his dimples. His dimples are so cute! By the end of 38 days, when all you’re doing is staring at the people in your cast, you go to a challenge and see Jeff, you’re like, ‘Thank the Lord!’ He’s so darn cute. I love him!”

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