It’s a long-accepted rule that on the golfer’s backswing, his shoulders should turn to form a 90° angle with the target line. But without looking into a mirror, how do you know if you’ve reached the magic number?

Shoulders Under Chin for Proper Golf Swing Rotation

Easy: Your left shoulder should be directly beneath your chin.

It’s OK if your chin and shoulder touch, as long as your head is raised enough to allow the shoulders to complete the turn. In fact, if you struggle to rotate the shoulders fully, your problem may not be a lack of flexibility or technique. Try raising your chin at address – it may solve the issue.

But what about the downswing and follow-through? How do you know if you’re correctly rotating the shoulders into and through the shot?

The shoulder-under-chin rule works here as well. This time, though, it’s the right shoulder.

Make a slow-motion swing and stop when the right arm and club shaft are parallel to the ground (pointing toward the target) on your follow-through. Your right shoulder should be under your chin, with the shoulders again forming a 90° angle to the target line. If your chin has moved slightly left at this point, no worries. The right shoulder’s rotation will naturally push it this way.

To ingrain and maintain proper shoulder rotation, practice swinging while moving the left shoulder under your chin going back, and your right shoulder under the chin swinging through. It’s a simple way to boost your efficiency and power.