Bottom-Up Power
10/18/2006
Ask my 4 year-old daughter what makes her
chariot -- also known as our minivan -- go and she will reply
without hesitation.
The wheels.
This answer makes complete sense. She assumes that the
wheels, since they are on the ground and turn when the car goes,
must provide the force that makes the car move. Of course, the
truth is that the wheels are just the last link in a chain.
Pressing on the gas pedal leads the engine to produce more power
which is then transmitted by the transmission to the wheels and
the tires.
The problem is that many people make the same mistake
when it comes to baseball pitching.
Ask them what makes a baseball go and they will without
hesitation reply, "The arm." They assume that, since the arm is
the thing that holds the ball and that does most of the moving
during the course of a throw, it must be the thing that is
generating most of the power.
However, the truth is that, quite counter intuitively,
the thing that provides most of the force in a throw isn't the
arm, it's the body. Somewhere around 80 percent of the force in a
throw is generated by the muscles of the torso; the arm can
accurately be described as largely just along for the ride.
How can this be possible?
Well, it all comes down to something called the kinetic
chain.
When a high-level thrower -- be they a pitcher, outfielder,
or position player -- throws the ball, they start out sideways to
the target. As they break their hands, they then take a step
toward the target. This step is critical because it opens up the
hips -- starts them rotating -- while the shoulders stay closed.
This stretches the muscles of the torso until they reach the point
where they can't stretch any more and they contract and powerfully
pull the shoulders around.
Casey Fossum
This picture of Casey Fossum of the Tampa Bay Devil
Rays is my favorite example of what this process looks like in
action. Notice how his hips have opened and his belt buckle is
facing Home Plate while his shoulders are still closed; they have
yet to start turning and are still facing First Base. As you can
imagine, this stretches the muscles of his torso and enables
them to powerfully pull his shoulders around. It is only by
throwing with his entire body that a string bean like Casey
Fossum, who has no muscle mass to speak of, is able to throw the
ball 90 MPH.
Nolan Ryan You can see the same in action in
pictures of pitching greats like Nolan Ryan. Notice how in the
photo above Nolan Ryan's hips have started to open to face Home
Plate while his shoulders are still closed and facing Third base.
In a moment his hips will pull his shoulders, and his arm, around.
That's what I mean when I talk about throwing with your
body.
All of this may seem like just an academic exercise
until you realize that, unless you understand how you actually
throw the ball, you are going to have a hard time improving how
hard you throw the ball.
If you think you throw with your arm,
then you will waste your time focusing on your arm action,
scapular loading, and increasing your arm strength by building up
your biceps and your triceps.
If you understand that you throw with your body, then
you will spend your time working on the muscles of your hips,
legs, and torso; in particular, you will focus on the muscles that
rotate your torso. You will also work on a couple of
mechanical things as you throw...
-
Ensure that you are
sideways to the target before starting to throw.
-
Ensure that you step
directly at the target.
-
Ensure that your
hips rotate ahead of your shoulders.
-
Ensure that your
shoulders stay closed (e.g. don't rotate) for as long as possible
while you step toward the target and your hips open. Pointing the
glove at the target can help you work on this, because when you
point the glove at the target, your shoulders are closed. The
longer you can keep your shoulders closed (and the glove pointing
at the target) while your hips are opening, the more you will
stretch the muscles of your torso and the more powerfully those
muscles will pull your shoulders around.
SUPPORTING RESEARCH
The idea that most of the force in a throw is generated by the
body, rather than the arm, is supported by scientific research.
Throwing starts with the legs and
trunk, not with the arm. The legs and trunk make up your "power
zone."...Forces are initiated in the legs, then transferred to the
upper body through the trunk, and finally applied to the ball by
the hands and fingers...Assume, for example, that the player has
to generate a force of 1,200 lb to throw 90 mph. The legs
contribute 600 lb; the trunk yields 400 lb; and the arm, shoulder,
and hand yield 200 lb. (1 p. 154)
Bryan, Labossiere, Coleman, and
Bartz. Baseball Shoulder and Elbow Injury Rehabilitation of
Varsity, High School, Intercollegiate, and Professional Baseball
Players. Sports Medicine and Arthroscopy Review 9:154-164
(2001).
FURTHER EXAMPLES
I know that some people find this idea of focusing on throwing
with the body, and not the arm, a little disconcerting. As a
result, let me give you some more examples of what this looks like
in action. In each case, notice how the pitcher's belt buckle is
facing Home Plate while their shoulders are still facing Third
Base (or First Base in the case of the lefties).
 Danny Haren 
Scott Kazmir 
Wilfredo Ledezma 
Jon Lester
Steve Trachsel 
Justin Verlander |