Led by a video projected on to a whiteboard nine children, a mix of Latinos and African-Americans, walk or jump on the spot, swing their arms, stretch and reach in an exercise class that lasts around 15 minutes.

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Gibbons are the exception, they can swing, walk and climb, and they can jump.

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And I want them to think -- and this is something that Dean said -- if Dean can run all the way across the country, then I want you to think, as kids, as Dean would say, that you can at least walk a mile, maybe run, you can go outside and play, you can jump, you can do whatever.

WHITEHOUSE: Run Across America at the White House