You're Correct!

Extending the left arm throughout the back swing is not absolutely necessary to play good golf but it can definitely help improve consistency.

At impact the left arm extends and forms an almost straight line with the club shaft. If the left arm becomes bent during the back swing it must straighten on the way back down to the ball. This straightening of the left arm during the down swing can actually help increase distance but will cause inconsistency. The easiest way to achieve a repeatable arm swing is to keep the left arm extended.

The Straight Left Arm

Keep the left arm straight during the back swing does require a certain amount of strength and flexibility. If you are unable to complete the following swing sequence it would be advisable to undertake some strength and conditioning work.

• Taking a neutral grip and solid posture, begin to swing the club away ‘long and wide’.
• As the club shaft reaches parallel with the ground, the left arm and shaft should form a straight line extending away from the target.
• From this point in the back swing the shoulders continue to rotate and wrists begin to hinge upward.
• At the top of the back swing, the left arm should point straight towards the sky and the club towards the target.
• This extension of the left arm should be maintained as the hips turn and the club is delivered into impact.

Golfers looking to improve consistency of strike should look to keep the left arm extended throughout the back swing using the sequence detailed above.

When trying to keep the left arm straight, use the word ‘extended’ rather than stiff. This is because stiffness in the golf swing causes tension whilst extension will allow the body to turn without constraint.

As the back swing reaches the halfway stage, the right arm will begin to fold and tuck into the body. This should not be resisted and trying to straighten the right arm will lead to a number of problems.

It is often easier to keep a straight left arm when the back swing is shorter, however, this will decrease the amount of power available to the golfer.