Downswing and Impact
The most common error that the average golfer makes as they bring the club down to impact is to misuse the lower body. Most seem to believe that because the hands and arms bring the club back, they should bring it down. Although logical it is completely incorrect.
The "hands and arms" downswing stems from the desire to "hit the ball" rather than to swing through it. "Hitting" is an aggressive act that excites us - we want to do it as soon as possible. By actively using our hands and arms in the downswing our wrists almost always un-cock too soon, usually as the hands are about shoulder high. This action is what gives birth to such terms as "casting" and "throwing from the top." As many of you have probably experienced these actions result in shots that slice severely to the right or are pulled dramatically to the left.
What should generate the downswing momentum of the club while also eliminating conscious use of the hands is lower body action. Just as the club reaches the height of its backswing the hips "pump" or slide to the left. This places the hands in a "lagging" position behind the ball which will bring them properly into impact.
The initial direction of the downswing pump it lateral. It is a slide to the left on a line parallel to the target line. This action is the most critical in the evolution of a good downswing. There are many well intended comments made from teachers, writers and telecasters that are meant to explain a certain action in the downswing which all too frequently are misunderstood. Terms such as: "Get the left side out of the way" and "Clear the left hip" confuse too many golfers and they believe that they are to turn the left side to the left as soon as the downswing begins. This is one of the most common faults in golf today and a certain way to guarantee high scores.
If you get the left side "out of the way" before making a slight lateral slide you tend to straighten the left knee and pull your body away from the ball. This action results in what we call "spinning out." When you spin out you thrust the right side of the body outward toward the ball, which in turn brings the club across the ball from the outside to inside the target line, causing a slice or pulled shot, depending on the clubface alignment.
In reprise, by beginning our downswing with the lateral pump we place our hands in the lagging position which will allow us to hit the ball from slightly inside the target line which will produce more solid and thus better shots.