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What
are Shaft Lead and Shaft Lag?
For the technically
minded golfer, a frequent question that we encounter is exactly
how does a golf shaft bends during its down swing? And how does
the bending affect your shaft selection?
This is a subject
matter that, to our knowledge, has never been covered by any golf
publication before. We are happy to share with you what we know.
First of all, everything on this planet is affected by gravity.
Therefore, throughout the entire downswing the golf shaft will bend
downward to a varying degree due to gravity. People in the golf
industry have called this phenomenon drooping or toe down deflection.
This downward
bend will affect your lie at impact. That is why the best way to
determine a proper lie is to swing the club over a black rubber
matt and see the location of the scratch mark on the sole. If the
scratch mark is near the heel, the lie is too upright. If the scratch
mark is near the toe, the lie is too flat.
Now that we
are done with the gravity issue, let's talk about the shaft bending
induced by your swing. Please keep in mind that we can only address
this issue in general terms, because after all each golfer's swing
is different. Shaft lead occurs as the golf shaft bends forward
in the direction of the swing plane. Shaft lag results as the golf
shaft bends backwards in the direction of the swing plane.
On the down
swing, at around the 10 to 11 o'clock hand position, a golfer will
generally engage his initial load. In response, the golf shaft will
lag. Upon reaching the peak of his initial load, the acceleration
rate will drop while the player's swing speed continues to increase.
Therefore, at around the 9 o'clock position, the acceleration will
pass the initial peak and the shaft will transition into a leading
position, forward bending.
The golf shaft
will stay leading unless the golfer engages a second load, commonly
known as delayed release or wrist snapping, at 7 to 8 o'clock hand
position. A moderate delayed release will likely bring the golf
shaft to a relatively straight position. A strong delayed release
will cause the shaft to lag again.
Looking at the
acceleration pattern alone, a strong delayed release will produce
a secondary peak of acceleration. Whether the golfer has one peak
or two peaks in his acceleration pattern, his swing speed will continue
to increase throughout the down swing prior to impact.
What does this
whole picture mean? If the shaft leads forward at impact, the golf
shaft will not contribute much to the kick that golfers are seeking
to get that extra distance. Therefore, most respected golf instructors
today teach delayed release to keep the golf shaft in the position
of a slight lag to give the golf ball an extra kick. It is like
pulling back a bow prior to releasing an arrow.
Shaft lead will
occasionally cause an unexpected problem that is more commonplace
with better golfers. If the golfer is an excellent golfer who happens
to generate shaft lead, he will naturally be counting on having
the shaft lead to give him a little bit of timing advantage because
the club head is traveling ahead of the shaft with a slightly closed
face. If this golfer loses the lead, he will push the golf ball
to the right.
How about delayed
release? A common problem we encountered is shaft lag combined with
a slow-recovering golf shaft. It is like pulling a bow with a loose
string. You can guess that the arrow will not go very far. The stronger
the delayed release the golfer has, the faster the shaft recovery
he needs to have to optimize the performance of his club. This is
one of the reasons why we integrated titanium into our graphite
matrix to take advantage of the high memory that is inherent in
titanium to provide a fast shaft recovery.
Shaft lead or
shaft lag bring about unique issues that every experience club fitter
need to consider to derive a satisfactory solution to a golfer seeking
assistance.
Most
readers of this article are also interested in:
Shaft
Twisting - A Common Cause of
Hooks and
Slices
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