I've watched this several times and get tired doing so, but enjoy it all the same. Perhaps sometime in your life you've had dance lessons and at one point you were able to perform like this. If so, you have remained trim, for sure.
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The dance was popular in the 30's and 40's, thus the Boogie Woogie Bugle Boy performed by the Andrews Sisters, and was not more than an image I kind of knew about during our decade. Wikipedia has an interesting article on it, wherein it describes the "twelve-bar" blues format.
To watch the above, you really need to click the full-screen icon, play it on a 23-inch monitor, and use good speakers. It's just fun. I swear the dancers never break a sweat.