Death To The Inverted W
This page, which dates back to
contains my original thoughts and theories about the Inverted W
If you are new to the subject, I have since
put together a new overview piece...
...that also addresses
what Jeff Passan said about the Inverted W, my work, and me in The Arm.
In sum, and
as I have
said since 2007, the Inverted W is only a problem if
it hurts a pitcher's
The Inverted W, which I initially called
M, is a pitching arm action that I believe is one of
the driving forces behind the
pitcher injury and tommy john surgery epidemic
because it can create a problem with a pitcher's
As with the other inverted arm actions, which includes the
Inverted L and the
recent studies have shown that...
Pitchers who make the Inverted W, and
who have a
Timing problem as a result, are at an elevated
risk of experiencing shoulder and elbow
I also use the term
Flat Arm Syndrome to refer to the
Timing problem that tends to result
from the Inverted W.
Nature or Nurture?
In the interests of accuracy in journalism, I initially
held off on publishing this essay because I wasn't sure if
pitchers were actually being taught to do this or if they were
simply figuring this out on their own (and being praised for it). However, I
decided to publish this piece after having an exchange with
a pitching guru named Paul Nyman in one of the forums on Steven Ellis'
Lets Talk Pitching
web site where he indicated that the Inverted W is indeed
something something that he advocates...
I can point to literally hundreds of players
who have benefited significantly using the exact same methods
(inverted W, scapula loading, pelvic loading, etc.) that you THINK
are a problem or what you THINK causes problems.
The Inverted W Defined
For those of you with medical or other scientific
backgrounds, let me give you a more technical definition of the
I define the Inverted W as being more than 90
degrees of shoulder abduction with the Pitching Arm Side (PAS) elbow above the level
of the shoulders (aka
hyperabduction) combined with 5 or more degrees of shoulder horizontal adduction (PAS elbow behind the shoulders).
In the Inverted W, the Glove Side (GS) and PAS upper arms are both elevated. In the
L, only the PAS
upper arm is elevated.
WHY I Don't Like The Inverted W
Let me explain why I don't like the Inverted W.
It Is What Many Frequently-Injured Pitchers Do
If you look at the pitching mechanics of pitchers who have had
injury-plagued careers, you will often see the Inverted W or one
of the related inverted arm actions, the
and the Inverted
Mark Prior's Inverted W
If I am correct
about this, then I believe a number of young pitchers will
experience problems as a result of making the Inverted W, especially if they are moved into, or continue to pitch in, the
Jeremy Bonderman's Inverted W
Anthony Reyes' Inverted W
Adam Wainwright's Inverted W
C.J. Wilson's Inverted W
Shaun Marcum's Inverted W
Pitchers who make the Inverted W include...
Smoltz had a relatively long career despite some Inverted W
in his arm action...
John Smoltz's Inverted W
...but Smoltz's career started to come off the rails in 1998
after just ten years and, from that point
on, he struggled with elbow and shoulder
problems and was forced to move between the starting rotation
and the bullpen in an effort to try to manage his injury
It Is Not What Great Pitchers Do
If you look at the pitching mechanics, and in particular the
arm actions, of great
-- and by great I mean pitchers who had
long, successful, and relatively injury-free careers -- pitchers like Randy Johnson, Greg Maddux, Nolan Ryan,
and Tom Seaver, you will see that none of them made the Inverted W.
While you can say that all of
these pitchers employed
Scapular Loading, I would argue that the
critical difference is that their elbows never got above the level
of their shoulders. As a result, they didn't develop the
problem that is the root cause of the problems that Inverted W
pitchers tend to experience.
Inverted V and the
Inverted L, the Inverted W is
not (that) bad in
and of itself.
The Inverted W doesn't directly lead to injuries.
Instead, the problem with the Inverted W is that it can create a
problem where the PAS forearm is not in the proper position at the moment the GS foot lands and the
shoulders start to rotate. That
problem will tend to increase the distance, and thus the force,
with which the PAS upper arm externally rotates and
increase the stress on both the elbow and the shoulder.
You can see this
Timing problem in the clip above of Anthony
The thing to notice is the position of Anthony Reyes' PAS
forearm in Frame 41 at the moment his GS
foot plants. Notice how Anthony Reyes' PAS forearm is
horizontal, rather than vertical, in Frame 41. Anthony Reyes'
PAS forearm isn't vertical until Frame 45, at which point his
shoulders have rotated significantly.
You can see the same thing in the picture above of Mark Prior. The thing to notice is how
much Mark Prior's shoulders have rotated, and how much his PAS
elbow has pulled back, but his arm still hasn't reached 90
degrees of external rotation.
That is the telltale of an arm
that is quite late.
You can also see a Timing problem in the picture
Stephen Strasburg. Notice how his foot is planted
and his shoulders are starting to rotate, but his arm
isn't in the correct position.
Instead of being UP at the moment his front foot plants,
Stephen Strasburg's arm is FLAT.
For obvious reasons, I call this
Flat Arm Syndrome.
Finally, it was Joba
Chamberlain's pitching mechanics that alerted me to importance of
Timing, rather than the mere position of the arms, to pitching
I go into greater detail about
the scientific basis for why the Inverted W is problematic
elsewhere, but if you are interested in a more technical,
anatomically-based explanation of why I think this is a problem,
then let me give you one in the form of an e-mail I received in April of 2007...
I am an orthopedic
surgeon, and would like to offer you a theory on why the
Inverted W is bad for the long term health of the shoulder.
In the position of hyperabduction, elevation and extension of the distal humerus above the shoulder (inverted W) the inferior glenohumeral ligament is placed on stretch. The humeral head must lever against it to advance the arm forward. This ligament is the primary anterior stabilizer of the glenohumeral joint with the arm elevated
(i.e. pitching). In other words, this position places this ligament under tension, then it is levered against in order to throw. This eventually will either loosen the shoulder, or tear the anterior labrum.
It should be recognized this ligament is under stress during the "normal" delivery. If you traumatically dislocate your shoulder, this ligament is a key part of the pathology.
Shoulder instability in turn leads to impingement, and other problems. Conversely, when the elbow is below the shoulder, this ligament would not be as stressed.
Also, the specific use and timing of the muscles about the shoulder is critical.
They have done muscle activity studies during throwing, and there are distinct
differences between amateurs and professionals. There is also evidence for muscle
use differences in the healthy shoulders, and the ones that aren't.
I'm not sure he's
exactly right about why this is bad, but what he says is
interesting enough to make me think I'm on to something.
Recognizing The Inverted W
If you look at the arm actions of guys like Randy Johnson, Nolan Ryan, and Greg Maddux, you
will see that their Pitching Arm Side (PAS) elbows never get above the level of their shoulders.
You can clearly see this in the video clip above of Randy Johnson. While at first blush it looks like his PAS elbow gets quite high, if you take into account the
fact that Randy Johnson leans forward toward First Base during his stride,
you will see that his PAS elbow actually stays well
below the level of his shoulders (the yellow line in Frames 43 and 49). You
can also see this in the photos below of Nolan Ryan and Greg
Notice how their PAS elbows are well below the level of their
shoulders after they break their hands.
The Standard W
In particular, at the point of maximum scapular loading their
elbows are below the level of the shoulders and the hand. This forms the shape of a "W" (the green lines in the diagram
This is visible in video clips of Greg
Maddux. You can also see the
same thing in still photos of Greg Maddux.
In contrast, if you look at the arm actions of pitchers
Mark Prior and Anthony Reyes, you
will see that, after they break their hands, their elbows go above
and behind the level of their shoulders.
Viewed from the side, this forms the shape of an Inverted W (the red lines in
the diagram below).
The Inverted W
Some people will argue that I am comparing apples
and oranges because what I am describing are two different points
in time when I compare the Standard W to the Inverted W. While
this is true, it doesn't matter for two reasons. First, pitchers
who make the Standard W never let their elbows get above the level
of their shoulders. Second, the problem with making the Inverted W is that it increases the distance and force with which
the PAS upper arm will externally rotate. This increases the
stress on both the elbow and the shoulder.
Points Of Confusion
I have recently discovered that there is some confusion among
my readers about exactly what is (or isn't) the Inverted W and
who exhibits it (or doesn't). One example of a player about which there is confusion,
possibly due to prior confusion or lack of clarity on my part, is Carlos Marmol of the Cubs.
While it looks like Carlos Marmol is making the
Inverted W in the photo above, I do not think he actually is.
That is because he is leaning forward toward Third Base in this
photo. As with Randy Johnson, that
makes his PAS elbow look quite high. However, his PAS elbow does
not seem to actually get above the level of his shoulders, which is a key
characteristic of the Inverted W.
the Inverted W in the News
The Inverted W has been in the news a lot, in part because of
Adam Wainwright's recent elbow problems, so I wanted to address
some pieces that discuss it.
I've got to give two thumbs up to Doug Thorburn. Until recently,
he wasn't a fan of the Inverted W and thought the problems that
the pitchers who utilized it were likely due to other things.
in this piece , which is a triumph of intellectual honesty, he acknowledges the evidence and agrees that there may indeed be
something to the idea that the Inverted W is problematic.
Despite Doug Thorburn's possible conversion, some people are still
either not fully understanding what the Inverted W is or they are
still not buying that it is a problem. I discuss my arguments for
why I believe the Inverted W is problematic, and the research that
backs up my ideas, at greater length in my new piece on
the scientific basis for my theory about why the Inverted W is
A recent piece by Tom Verducci in Si.com
about Stephen Strasburg and the Inverted W -- a piece that,
without attribution, pretty much just cuts and pastes from some of
the key sections of this and other
articles by me -- is getting a lot of attention. However, because
Verducci "borrows" my ideas without really understanding them, he
gets multiple things wrong. In my updated piece on the
pitching mechanics of Stephen Strasburg, I go over what
Verducci gets right and what he gets wrong.
Finally, I just put together a piece that discusses
the overlap between pitching mechanics, injuries, the Verducci
Effect, and Pitcher Abuse Points. The bottom line is that,
while I do think abuse and overuse are important, I think pitching
mechanics ultimately explain why some pitchers fall victim to The
Verducci Effect while others don't.
About The Author
Chris O'Leary never played baseball beyond grade school due
to a shoulder injury suffered due to poor pitching mechanics. As
a result, he is focused on ensuring that what happened to him
doesn't happen to anybody else.
The Epidemic is one way he hopes to achieve that goal.
 Unfortunately, I'm not sure I can
continue my praise of Doug Thorburn. That link isn't active any
more and the piece seems to have been taken down. However, thanks
to the Wayback Machine, you can read the piece