Did you know Major League Hitters have a linear press forward first? Back leg controls this movement by "abduction".
Coaches say stay square to the plate but tell kids to spin the back foot and get more hips involved. That would confuse any kid. It's physically impossible through the Kinetic Chain of the body to spin your back foot and stay square to the plate. Look at Josh Hamilton's back foot at contact. It does not and has spun.
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