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Kate Gosselin was among Barbara Walters' most fascinating people of 2009 (see her complete list here).

But who topped the reality mom, 34?

First Lady Michelle Obama.

During her tenure as first lady, Walters praised Obama, 45, for promoting healthy living and taking steps to combat childhood obesity -- creating a vegetable garden on the White House lawn and holding health fairs with exercise stations for kids.

"I think I've begun to lay the foundation to a conversation about the health of our kids -- particularly when we're looking at statistics that say that one in three kids in this country are obese, and those numbers increase if you're African-American or Hispanic," Obama told Walters on her special Wednesday night. "So we're going to spend a lot more time on that issue in the years to come."

Walters also remarked on Obama's famously toned arms. (Obama wore a sleeveless top during her chat with Walters and famously wore a sleeveless dress in her official White House portrait.)

Obama told Walters that she's been working out extensively since the birth of their first daughter, Malia, in 1998.

"My personal routine hasn't changed much in the past 11 years," she said. "I really started right after I had Malia, our oldest, and some of that was, you know, in all honesty it was a little sort of revenge because I'm married to a man who has worked out all of his life. And regardless of how busy he is, he finds the time to work out. And there was a point at which I got a little resentful of that.

"[Malia] was still waking up for that 4 o'clock feeding and I'd get up because I'd be the first one to hear her, and he'd be asleep," she added. "And I thought, 'I'm up, I might as well go to the gym. And if I get to the gym, then he'll have to wake up and do that feeding.' I get a workout in and everyone will be happy. So you know, if there's anything that I can attribute these arms to, it's probably just determination."