Athletes often swing their arms and warm up before a game.

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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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He had long arms and big hands he could swing like a hammer.

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Their long, heavy arms, good for hanging from branches, act as pendulums to swing their weight forward as they uncoil from the crouch.

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