I saw an amazing golf lesson the other day. I was sitting in on a lesson of a golfer who I thought had a great swing. His swing plane looked great to me, the untrained non professional.
The instructor had this guy only work on one thing, posture. (Many good instructors will give a student only one thing to work on or think about). A quick look from the video camera showed that the student was actually slouching. His shoulders where rolled over as well.
The instructor had him hold a club away from his body parallel to the ground while standing straight up. The goal was to try to push the shoulder blades together. Then he dropped the hands to belt level, but kept the club parallel to the ground. At that point the instructor had the student simply bend over until the club was in position. Instantly the players stance looked more like Charles Howell than a slouching hacker with a hunched back.
When the student hit shots from this better position the change was amazing. First the players hands were in a better position. Before his hands were too close to his body, causing some possible re-routing issues. The player’s swing plane suddenly changed from a two plane to a one plane swing all the way through. Last, when freezing the video at crucial points, the properly adjusted posture put the club face at perfect positions at 1/4 back, the top of the swing and completely through the follow through.
Simply making sure you have good posture can help fix many other problems you may be having in your swing. Check it out in front of a mirror.