Senior golfers can use this drill to correct their golf swing as it helps to create a more stable left side through impact and promotes a correct weight shift during the downswing.
Having a stable left side at impact means that you have created a 'power line' down your left side at impact. Your left shoulder, left hip and left knee are all vertically above your left foot. Your left arm is straight and pointing vertically down towards your left foot and your hands are in front of your left thigh. You have 75% of your weight on your left side and your pelvis has rotated towards the target.
You can work on achieving this position if you stand next to a wall on your left side, or in a doorway. Swing the club away and then work on moving your left knee, left hip and left shoulder in that order to the wall, as you turn your pelvis towards the wall and shift on to your left foot, before the club reaches the wall. However, doing this with a wall does not allow you to actually hit balls. Use the step through drill and you can begin to strike golf shots.
Swing the club away from the ball and on your downswing, step your right foot over your left and land it pointing towards the target on the target side of your left foot. Your left foot will remain planted and not move.
You can do this drill as you hit balls and it will encourage you to shift your weight on to your left side, to rotate towards the target and to keep your left side firm as you swing through the golf ball.