HOMESTEAD, Fla. -

First lady Michelle Obama visited South Florida on Friday to continue her fight against childhood obesity.

VIDEO: Preps for visit by Michelle Obama

The Homestead YMCA Family Center was filled with dozens of children, their parents and volunteers an hour before the first lady was expected to arrive.

As though the crowd wasn't already pumped up, a YMCA volunteer led everyone in a series of jumping jacks and arm-whipping jump-rope moves. 

"Are you ready?" he shouted. 

"Yeah!" the crowd replied.

When the routine was over, kids were encouraged to drink water and help themselves to the snack table, which was full of packaged apple slices, granola bars and veggie chips.

When Obama arrived at 4:10 p.m., she was joined by pediatricians and experts from the popular medical website, WebMD. The first lady and the doctors focused on physical fitness and the importance of eating healthy.

The first lady spoke about what she and her family eat, the importance of exercise and sleep and what parents can do to play a role in what their children eat in school.

This is all part of Obama's national initiative called "Let's Move," which is designed to help fight childhood obesity. Obama has appeared in schools across the country, including Dallas and Arkansas, speaking to students about eating healthy.

Obama also spoke about the importance of parental involvement.

"It's really important for you to keep an eye on what's happening in your kids' lunchrooms and you definitely should ask questions," she said.

This time of year it might seem like all politics and mud, but to the kids in the audience, the first lady was all brain and brawn.

Friends Isabella Star and Destiny Torres said they liked Obama’s advice for staying fit.

“My favorite piece of advice from her was getting the parents out there and playing with their children,” said Star.

“Getting outside and get moving,” said Torres.

One student in the crowd, Jossiah, Brower, even got a signed t-shirt for doing the moonwalk, his favorite dance to keep active.

“I got it signed by the First Lady,” he said as he held up his autographed shirt.