Deceleration happens the moment you put your front heel down. Your forward movement is arrested energy is transferred from back to front into a firm front side. You lowerbody decelerates while you upper body accelerates, Upper body deceleration would be after extension. The is some argument of whether there is deceleration of the hips to whip the arms but most of that hip declaration occurs after contact.
How far do your hips go and how far do your shoulders go?
depends on pitch location and timing. as well as set up aka stance and mobility. Think Trout and JD.
also don’t think shoulders, the measurement would be hips and trunk.
Understand but I don't understand how you teach deceleration. I know it happens to some degree but not sure how you teach it. My DD can crush the ball for her size (isn't consistent), she tends to go after the ball with her arms and get disconnected on a lot of swings. It seems to me that staying connected until contact is what causes deceleration but really don't know.
You are hoping to 'teach' decelerating?
Understand but I don't understand how you teach deceleration. I know it happens to some degree but not sure how you teach it. My DD can crush the ball for her size (isn't consistent), she tends to go after the ball with her arms and get disconnected on a lot of swings. It seems to me that staying connected until contact is what causes deceleration but really don't know.