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During a time when we hear so much about the shoulder turn, the pivoting of the hips, I feel the structure (radius) of the armswing is overlooked and under-coached. To maintain a proper radius (a major speed source), never allow the right arm at the elbow joint to fold beyond 90 degrees. This will keep the left arm in an extended condition. Mirror this on the forward swing with the left elbow joint and
the right arm and the radius of the armswing will be a huge aid in creating speed in your swing.

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