Tyra Banks showed off her buff new arms on a recent episode of The Tyra Show.

The talk show host, 35, says she and seven friends challenged themselves to a three month "get fit, get healthy challenge" beginning this January.

"At first it started as a game ... and then it actually turned into a lifestyle for me," she says. Banks wrote down every single thing she ate, which made her more cognizant of the calories she consumed while eating out "14 times a week" and bought an elliptical machine, she explains.

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"I didn't work out like crazy, [but] I would exercise," she says. "I actually bought a treadmill and elliptical. I got rid of one of my couches in my living room and I watched Sex and The City episodes on the elliptical and treadmill. So Sex and The City lasted 30 minutes and that's how long I was on the elliptical."

Banks says her slimmer looks have earned her some attention. 

"I thought it was going to be private thing me and my friends were going to be doing, but then the media started taking notice and showing pictures of before and after and me losing weight and I felt kind of exposed because I wasn't trying to proclaim to the world 'I got fit and I got healthy and I got in shape' because I felt kind of conflicted.  Especially, after the kiss my fat ass thing. It's still fat by the way. I just feel better inside. No more stomach aches!" she jokes.

Banks says she had to train herself to work out. As a model, she says she "used to just rely on metabolism" but that changed as she aged.

"My career as model changed because my metabolism changed. I didn't do Victoria's Secret because I wanted to. I did Victoria's Secret because my ass was getting big and I couldn't fit in Armani runway anymore," she admits. 

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