The idea of the golf swing plane is one that tends to be quite confusing to most golfers. Here is a drill to help understand and practice swinging on plane more consistently, which will allow the ball to be both hit straighter and with a more consistent ball strike.
The swing plane in basic terms is the circle around the body that the club would ideally swing backwards and forwards on. It is determined by the angle of the spine at the set up position and the length of the golf club being used. When the club is swung on plane this means that the club travels straight through the golf ball towards the target at the impact area. If this is not the case, the club can be described as swinging through the ball in two other ways. For a right handed golfer, the club can pass right to left through the ball, which is also known as an out to in swing, or left to right through the ball, which is known as an in to out swing. These are opposite for left handed golfers.
To swing on the correct plane, it is the big muscles that need to power the golf swing. During the backswing we should keep as still as possible, with the feet flat on the floor, and the knees staying flexed throughout the movement. The hips and shoulders rotate and the arms stay fairly still while the wrists hinge. If these movements are performed well in the backswing, the club will travel around the spine and the feeling should be that the club passes around the body and behind, rather than a lift of the club up into the air with the smaller muscles such as the hands and arms.
Following the circular backswing, ideally, there would be a turn through the golf ball mirroring and matching those movements on the other side of the swing. Here, the big muscles turn through the ball, with the hips and chest facing the target, sending the arms, club and ball out towards the target. When performed correctly, the swing should feel effortless yet should produce great speeds. The club will also be directed down the line to the target much more easily, and therefore, there is a greater chance of hitting straighter shots.
To set up this drill, we use two tour sticks and put them into the ground approximately six feet apart and at an angle that is similar to the shaft of the golf club at set up position. There are now two distinct points to visualise the swing plane, and where the club should be at the halfway point of the backswing, and the halfway point of the through swing. These points help to keep the swing plane symmetrical and circular. Hitting the sticks with either the takeaway or follow through will be an indication of moving the club excessively out of plane, and thus, incorrectly through the ball.
Practicing this drill will develop better rotation and a straighter swing through the golf ball giving more consistency.