Many players tell me that they're trying to load their right side or get to their right side in the backswing, but in almost all cases, that player is sliding back instead of turning. The one thing you must do in the backswing is create space and an angle of attack with the lower body, which allows the torso to fully turn and load. In the backswing, the hips shouldn't have any lateral movement, but instead should turn in a clockwise direction while staying inside the width of your feet. If the hips slide in the backswing, it will almost always cause the right knee to straighten and will place the majority of body weight in the front foot (a reverse pivot). This will also cause the torso to under rotate, placing you in a weak position from which to start the downswing. The term loading should be thought of in terms of the torso turning behind the ball and the weight in the right foot moving from the ball of the foot at setup to the right heel at the top.
To help feel the proper rotation and load, try placing a shaft on an angle from the inside of your right heel to the inside of your left toe. Practice by making backswings where your hip angle matches that of the shaft on the ground. It's critical to keep your right knee flexed and your weight in your right heel at the top of the swing. Don't be surprised if your torso feels more rotated than normal, but your arms feel shorter. With the hips turned more sharply and your weight in your right heel, the club will travel on a more inside-out path, and you'll feel more powerful. If you struggle with slicing or an overall lack of power, this drill is a must.
The key to attaining a solid, powerful position at the top of the swing is to properly rotate away from the ball, which should place the majority of your body weight in the heel of your back foot. Sliding laterally away from the ball promotes a weak, reverse-pivot position.
Kevin Scheller works with a wide array of students, including professional golfers, top amateurs and recreational players.