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I was asked by a loyal reader recently to take a look at Joba Chamberlain's
mechanics due to the circumstances surrounding the Yankee pitcher recently.
In case you live under a rock, Chamberlain was placed on the 15-day DL a while
back with what was deemed rotator cuff tendonitis.
I don't think this injury by itself is something to be concerned about. It
seems the tendonitis resulted from overuse, likely from the transition of
relieving to starting. There doesn't appear to be any tear or long-term type
damage.
But as for Joba's mechanics, let me first sum up a couple of general thoughts:
His tempo is excellent, meaning the frames from the point his knee reaches his
upper most point to release is around 21 or 22 frames. The faster one's tempo,
the better in terms of velocity (usually). For reference, Ian Kennedy's tempo
is average, coming out around 26 frames.
Chamberlain is blessed with an extremely fast arm and generates excellent
separation between his torso and his hips to produce what can be plus-plus
velocity.
Joba's Adjustments
One wrinkle Chamberlain has added recently--since the middle of June judging
from the starts I've seen, is a brief hesitation in his arm action just after
he breaks his hands. This helps in preventing his arm from rushing through his
wind-up. In simpler terms, Chamberlain is essentially correcting certain timing
issues with his delivery that may have a negative effect on his control. Below
is Chamberlain at various points in the year. Going from left to right, the
animations are of Joba throwing his off-speed stuff in starts on 6/8 (slider),
7/19 (curve), and 7/25 (slider).
Notice how his throwing arm is further ahead in it's arm circle for his 6/8
start compared to his later starts. This is Joba giving his body a little more
time to get out in front before aggressively moving his arm through its arm
circle, which helps correct any issues where his timing is thrown off by his
arm being too fast for the body.
What's interesting is how over time, Chamberlain increased the frequency of
how often he utilized this hesitation. Chamberlain initially used the
hesitation when throwing just his breaking stuff. However, Chamberlain soon
began applying this hesitation with his fastball as well--not everytime, but
whenever he wanted to increase the liklihood of throwing a strike or even to
throw off the timing of a batter.
The hesitation isn't as exaggerated with his fastball as it is for his
off-speed stuff, but the change is still evident. The result is a fastball with
more command, but less velocity. This is because Chamberlain, when he hesitates,
is briefly stopping momentum in his wind-up. You can see this in the clips
below, where Chamberlain is throwing a fastball in his 6/8 start (left) and his
7/19 start (right):
Did the mechanical adjustment made by Chamberlain do the job? The answer is yes
, though the sample size is small.
BB% and IP by Month:
April - 6.8%, 11.1
May - 15.4%, 12.1
June - 12.1%, 25
July - 6.9%, 35.2
The change manifested around his June 25 start against Pittsburgh and he began
to use it more when he faced Toronto on July 11. Beginning with that Toronto
start, Chamberlain went on a roll, walking two batters in four starts before
the start in which he left for injury.
This kind of adjustment to his mechanics would not be a cause for injury.
The Risk of Injury
Not taking into consideration the increase in workload after Chamberlain was
moved to the rotation, the simple fact that he throws a baseball in the upper
90's makes the risk of injury higher.
However, there are a couple mechanical issues that may heighten Chamberlain's
risk of injury. For instance, his finish is pretty abrupt. Ideally you want to
give the arm a long distance to decelerate. By finishing so abruptly,
Chamberlain increases the risk of injury to his arm, shoulder, and even his
back.
With that said, he does firm up his front side, which is helpful in limiting
the pounding one takes on their shoulder.
Now, there have been some questions about Chamberlain's timing in that the arm
isn't in a loaded position at foot plant. I think this is debateable for a
couple reasons:
1. The video used to evaluate Chamberlain is 30 frame per second video, which
doesn't give us a good enough indication of where the arm is at the specific
point of time in which his foot plants. The angles used by the people who say
this aren't ideal and don't tell the whole story.
2. Is the timing problem consistent or an isolated incident? Does the center
field angle tell us everything we need to know? Can you pin-point the second
his foot is firmly planted on the ground? What about if we use the two side
shots below? Can we make a determination then? I don't see enough where I can
say with any certainty Chamberlain has an issue with the timing of his foot
plant. He very well may have a timing issue, but I need some cold-hard
evidence before stating something as fact.
What you'll also notice in the two above clips is just how abrupt Chamberlain's
finish is, which as I stated earlier, is my biggest concern in regards to
Chamberlain's mechanics. I like pitchers that bury their head downward after
release, allowing for a long follow through. Chamberlain basically springs
upward into an upright position very shortly after his release and inital
follow through, which makes it much tougher to achieve what is a long enough
distance for the arm and body to decelerate cleanly.
A couple of other outside factors we all need to be aware of in regards to
assessing the injury risk of a pitcher:
1. Changes over time - It's very difficult to know every change made to one's
mechanics over a long period of time, but Chamberlain has a history of changing
his mechanics and last underwent a pretty dramatic change to his mechanics
after he was drafted in 2006. If a pitcher changes their mechanics over time,
who's to say which version of a pitcher's mechanics incurred the most stress
on the pitcher's arm? My main point here is that the injury risk of a pitcher
shouldn't be limited to what a pitcher's mechanics look like now...we need to
know what the mechanics of a pitcher looked like in college, looked like in
high school, and looked like in Little League.
This isn't limited to just pitching mechanics; we're talking about a litany of
other factors at play--too many to go over in this article. This isn't to say
you can't identify various risk factors in a pitcher's mechanics. It's when one
declares a risk factor as the reason for a pitcher getting injured which is
problematic.
2. Past injury - Anybody with a history of injury is more likely to get hurt
again compared to somebody without a history of injury and Chamberlain has
battled injury before his time with the Yankees.
Final Thoughts
The bottom line is the Yankees should obviously be extremely careful with him
...and they are. Limit pitch counts when possible, control his workload, be
wary of any warning signs of fatigue--I know several teams use various
barameters on pitchers to determine whether a pitcher is tiring or pitching
through injury.
Also work to strengthen the tendons and muscles in the pitching arm to better
handle the stress of pitching. Perhaps the strengthening programs Chamberlain
has employed in the past weren't up to par. Or maybe he simply doesn't have
the genes that will allow his shoulder to handle the workload of pitching over
the course of many years.
One thing that struck me when I read Tom Verducci's tremendous article on the
mechanics of Tim Lincecum was this passage:
"From the loaded position, when the ball has come to a stop, it is accelerated
from zero mph to 90 mph in 3/10 of a second...
"If your entire body was accelerated at that rate of speed for over 60 seconds
you would die."
No wonder pitchers break down. Pitching, unlike most athletic activities, has
reached the limit of what is humanly possible. So while we are accustomed to
increasingly swifter sprinters, faster swimmers, longer drivers of the golf
ball and bigger football players, you will not see a pitcher throwing 110 mph.
The arm and shoulder are maxed out. Pushed any further, the shoulder would blow
, like an engine in a race car."
If the arm and shoulder are maxed out, it only takes so much more for the
shoulder and arm to reach their limits and suddenly...strain, inflame, tear,
rip of the labrum, the rotator cuff, the elbow. The risk rises the harder one
throws.
The Yankees can work with Joba to make his mechanics more efficient, can
strengthen the shoulder and the arm with a regimen that has proven to work, and
they can baby him as much as they like. But sometimes a team simply has to hope
for the best because even if a pitcher does everything right, there is still
only so many pitches in a player's arm before the arm begins to give way and
the pitcher loses the quality of his stuff. Just how many depends on many
factors, most of which the Yankees and other teams will never know. For the
Yankees sake, they should hope Joba is one of the lucky ones.
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