Don't forget, the right knee never leaves its original position. As the top half of your body is turning, the right knee must remain in the exact same position. When you are addressing the golf ball, the right knee has a slight flex. During the back swing, the right knee can not slide backwards nor can it straighten out and it can not flex more. The right knee is the foundation of the backswing, it takes on all of the force of the right shoulder turning and the hips resisting from turning. The right knee has to maintain this rock solid foundation so you can continue to turn the top half of your body against the bottom half.
When the golf club has reached the top of the backswing, the right knee will be there to support the upper golf club, arms, hands and upper body. If there is one part of the body that has to be in the correct position at the top of the backswing, it is the right knee. The function of the right knee is not only the foundation of the backswing. In the next section you are going to find out the value of the right knee in the downswing as well.