Casting, as it applies to
golf, is the most disastrous act a golfer can perform while swinging a
golf club. It refers to the motion made when one casts a fishing rod, and happens when the
wrist cock set during the backswing is released
prematurely. Golfers call this "coming over the top" or "starting the
downswing with the hands and arms". The start of the downswing should start with the hips, and the
torsional stress in the swing should pull on the shoulders. The
triangle formed between the shoulders and arms should not be disturbed by unconnected arm/hand movement. The hands
must stay "in front of" the shoulders at all times. One should attempt to keep the wrist cock established at the top-of-swing until
centrifugal force naturally uncocks the wrists.
A swing key that Sam Snead relied on to avoid casting was that the start of the downswing feels like it's originating from the pinky and ring finger of the left hand. Imagine pulling on the club with those two fingers, and you'll see how focusing on that eliminates any tendancy to "hit" at the ball with the right hand. It is this overemphasis on the dominant hand that causes the cast to occur. The golf swing requires patience due to the angular inertia of the clubhead. One cannot start it moving at 100 mph by making a hard move at the start of the downswing. The result of trying to apply too much power too early will be that of 90% of those who try too hard to hit from the top of the downswing: a wicked slice. The other 10% of those who hit from the top will be cursed with something almost as bad: a big pull. Neither of these is a desirable result, and both can be eliminated by being patient and allowing the power to flow to the clubhead in a smooth, on-plane fashion.