Full Swing Knee Bend
I’m going to tell you the role that the knees play during the entire golf swing. The correct posture in golf, in order to improve your golf swing, is that you bend at your hips, over the bones that are on both sides of your hips.
We don’t sit in this sport. We have our knees slightly flexed, and then we bend from the hips.
In the golf swing, the knees never ever get straight in the backswing. They stay flexed the entire way.
The game of golf starts and ends right here. Good players play the sport from inside the right knee as they turn. It doesn’t go out and it doesn’t go straight. But it stays where it was at the beginning of the backswing, so as we start back the knees don’t move.
Now, the downswing: As the arms start to unwind the knees don’t move at all. The centrifugal force, the speed of the golf club swings into the ground.
As the club passes you and your left hip starts to move out of the way, then, and only then, does the right knee start to get straighter in the downswing after impact.
And the entire time, make sure that you don’t lock your left knee in the downswing. Keep it slightly flexed as you swing through. You don’t have to come all the way up and straighten it up.
I think that that might help you improve your golf swing. Think about this tip a couple of times and make sure that this is what you're thinking of when you swing the golf club, in relation to your knees.