Keep That Left Arm Straight

BY Paul Smith

Walk around any golf course and you will hear sayings like “keep your head down, keep your left arm straight, swing along the target line or keep that clubface square to the line.” Each piece of advice is well intentioned, however leaves many with a question about how to achieve these gambits and whether or not they are being implemented correctly. In this article we will look at the role of the left arm.

Firstly, I wish to distinguish between the role of the left arm and the left wrist. We are talking here about the arm, not the wrist, which we will assume is a part of the arm for simplicities sake.

In the first article we saw that from a side view the down and out Freddy had a straight left arm as he swung. The overhead representation in article two showed the club’s arc is smooth. In both cases the role of the left arm was to maintain the radius of the swing. The club does not change in length during a swing, however the left arm can, and many play with it bent, whether it be slightly, considerably or inconsistently. This disrupts not only the radius but the plane also.

To avoid this kink many players make the common error to make their arm rigid as an iron rod to ensure it stays straight. This is not particularly successful as it restricts their pivot with all the tension it produces down the left side of the body. There is a technique to ensure you can not only keep the arm straight but also know you are continuing to do it throughout your swing.

Extensor Action

As the word suggests this simple method involves extending the left arm. First look at Figures 1 and 2. Here, I demonstrate extensor action with a simple piece of rope. Initially hanging loosely the rope has no rigid structure. By pulling the rope taut with my right hand it will maintain its structure, exact length and radius when swung.

Extensor Action Using Your Grip

Figures 4 and 5 show how to pull your left arm straight by simply pulling on your thumb. The left arm remains straight and retains swing radius. Imagine just pulling your shirt sleeve straight when you pull on the cuff. That is just enough pressure to do the job.

Extensor Action With Your Club

Translating this to your clubs you need to ensure your right hand overlaps your left thumb while gripping. Therefore you are gripping not only the shaft in your right hand but also your left thumb. This allows you to apply the same pressure to that left thumb as we discussed above. The important factor here is that it is not the left hand which is pulling down, thus causing the tension we discussed earlier, but the right hand pulling the left arm straight.

If you maintain the pressure of the right hand against the grip the left arm will remain much straighter in the rest of your swing. If the pressure is commenced at impact fix position whilst we are adjusting our impact alignments then the radius is set for the rest of the swing. If we do not then we will be searching for the radius while the swing is in motion.

Extensor action provides structure to your left arm which can otherwise flop around in an unsupported fashion if the pressure is lost. In the backswing as your shaft gets to parallel and above the pressure is still in the same direction and now may even seem to be a push outwards on the club rather than a pull down. This provides good pressure to get your right elbow away from your side. Lose the pressure, the left arm bends and the right arm does not reach its full power potential, the plane is lost and we are now searching for the right way back to the ball.

One note of caution here โ€“ do not overdo the pulling effort. You are not trying to pull your left arm out of its socket. If your left arm has a natural bend built into it then please do not look to straighten that out. That is how you are made and as long as you maintain the bend that is your radius. All we are looking to do is start with a “straight arm” and keep it that way.

So while the right arm goes on the search for the plane in the backswing, the left arm, whilst having a secondary role does have a major one, that is maintaining the radius of the swing and providing structure to the overall stroke.

Now we are ready to look at the role of the right arm in the backswing and what the mysterious plane actually is. This will take a few weeks to work through as there are lot of pictures and diagrams.

  • 11190
    About the Author: Paul Smith

    Paul Smith holds a Master Craftsman's rank certified by the Golf Clubmakers Association in the USA and is one of only 220 Authorised Instructors of The Golfing Machine (Bachelors in Golf Stroke Engineering). Clients get a first class education session whether it be fixing a swing fault or building clubs from scratch to suit a player's ability.


    Read all of Paul's articles ยป




Special Promotions

Teetimes Specials


View All Courses »