Followed the site for a while, so I know what Jack�s explanation would be, but it would be great if JJA, Nyman or one of the others versed in the sciences gave us the technical explanation (how it fits into Adair�s and other�s physics model) of what is causing Sosa�s bat to become a blur well back in the swing (starting in frame 10) of the following clip:
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> http://www.youthbaseballcoaching.com/mpg/Sosa01.mpeg
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>Forearm rotation is the violent action in this swing. Everything else you see is responding to that action....including the percieved leg drive. In my opinion. Beware I'm no scientist, I just like to hit the ball hard.