Analyzing Arm Slot: The Myths

This is going to be a little series on a pretty important part of pitching mechanics, arm slot.  In this piece I’m going to tell what an arm slot is, the rumors of arm slot, and how to properly obtain a decent (if not great) arm slot.

What is arm slot?

Arm slot in lay mans terms is the angle of your arm that you throw with.  In slightly more complicated terms, your arm slot is the angle at which you pitch from in relation to your body and typically comes in one of four varieties:  side, 3/4, overhand, and submarine.

Now as with most pitching aspects, conceptually this is simple.  However, there are rumors that cause pitchers to take an improper arm slot.

Lets dis spell the rumors.

Common arm slot rumors

1. An arm slot is a natural position and shouldn’t be changed. This one is easily dispelled.  Nothing about the act of pitching is in anyway natural.  You can try to make a motion and delivery as smooth as possible but it most certainly is never natural.  Another way to dispell this rumor is that if arm slot was indeed natural, no pitcher would, or could, change arm slot.  Each position is different, provides different advantages, and to even throw submarine you should have a special instructor.  Special instructors hardly equal “natural.”
2. Proper arm slot is created by bending the elbow. Arm slot is never achieved with the elbow.  It is always achieved by the shoulders.  Throw side arm, the shoulders should be flat.  Throw at 3/4, the shoulders should be tilted to a 45 degree angle.  Throw overhand, guess what?  The shoulders should be tilted be parallel with the rest of your torso.  With those three slots the elbow should always be a little be below the shoulder, even with a side arm slot.

Now I say this in practically everything I write, but it’s true across the board when practicing improper pitching mechanics.  Improper arm slot increases injury risk.  Not by leaps and bounds like other poor practices, but if loading rates are not properly maintained joints such as the elbow and shoulder can become overloaded.  Overloading causes injury.

Coming to Terms: Loading Rate

Term: Loading rate

Definition: The speed at which load is presented on a component.

Loading rate, in terms of pitching, is something that generally applies only to the PAS arm.  Basically in an overall sense, loading rate is a measure of how quickly the energy your body creates in the windup is transferred to the baseball in the delivery.  Now while the creation of this energy is a whole body process, the pitching arm is the most susceptible to injury due to overloading.  When the pitching is loaded too quickly, over extension is a problem and the various tendons and ligaments of the shoulder and elbow are subject to extreme amounts of force.  This over exertion on the shoulder and elbow is commonly known as overloading and is a direct result of loading to quickly.  It is important to remember that the sequence from the arm swing to the arm slot, to the loading of the shoulder and elbow should have a smooth and consistent transition from place to place to reduce risk of injury.

The Importance of Balance…

One thing I’ve spent alot of time talking about through this blog thus far is the actual motion.  In regards to velocity, location, arm slot…just general consistency in performance, what I’ve talked about is very important.  Every thing in the windup creates a kinetic chain which is used to transfer energy to the baseball and hopefully to the catcher for that all important third strike.

The most important word out of all that above paragraph is “consistency.”  Without it pitchers are just throwing.  Anyone could do it.  Luckily pitchers have something that keeps them separated from all the other lowly fielders out there.  What is it you may ask?  Well they can balance.

Here is what I’m not saying.  I’m not saying that you can just stick a pitcher up on a high wire and expect them to not fall to there death.  Pitchers just need to reach this point for a second.  And here’s why.

I’ll start with an extreme example.  Grab a ball and try to make an accurate throw at a target while falling sideways.  If you took me literally and fell to the ground from a full sideways dive, I laugh at you.  But my guess is that you didn’t hit exactly where you wanted.  Now put yourself in your most comfortable throwing position and try again.  Probably got closer right?

Now to apply to the pitcher.

Pitching is a matter of consistency.  Consistent start, consistent end.  The balance point in the windup can be thought of more as a checkpoint between the start and the end.  It’s right there before the pitcher moves forward.  Some glide on through, some stop there briefly.  Either way, you reach the checkpoint.  If the point isn’t reached properly, you aren’t going to reach the right destination.  It’s pretty simple really.  In absolute layman’s terms, balance right, pitch right.

I suppose now you’re wondering what this could affect?  Well it’s not really going to affect a pitchers velocity.  With pitchers, improper balance usually isn’t going to cause enough of a displacement of momentum to cause much affect to velocity.  Location however is subject to inconsistency with inconsistent balance.  Making a throw, or a pitch is all about lining up the body correctly.  Landing improperly on the GS foot for a pitcher can be quite bad, even if the difference is unnoticeable to the naked eye.  Pitching is an art defined by a strike zone.  You hit it you’re successful.  You miss it you’re not.  One single inch is all that stands away between a pitcher and success.

All in all, balance point is simple to understand, hard to execute, and in the game of pitching, separates the men from the boys.

The Magnus Effect…

If you’re reading this I’m assuming you’re a fan of baseball.  If not, than I assume you searched “Magnus Effect” in Google and are now here.  Either way I will try to teach in an easy to understand way.

Ok first off I’m going to assume we’ve all seen a baseball game.  If not, go watch one.

Now having got that covered, did you notice how when the ball was pitched or hit, it’s destination was different than it’s initial trajectory?  That my friends is the result of the Magnus Effect.  It is the direct result of the force perpendicular to the forward motion on a spinning object moving through a fluid.  Basically, the spin of an object can effect how it moves through a liquid or a gas.

So now the question remains, how does it work exactly?

Lets use our imaginations for a second.

Imagine you have a baseball in your hand and you throw it forward with the only forces working on the ball are forward motion put by you on the ball, the resistance of the air you’re throwing it through, gravity, and the spin your fingers put on the ball.  Now it’s easy to imagine the ball moving forward, air resistance slowing it down, and gravity pulling the ball down, but think about the direction of the spin you put on the ball with your fingers.  If you’re picturing what’s in my head, there was no wrist movement on the pitch, so therefore the resulting spin on the ball is upward looking from the front face of the baseball.  The direction of the spin tells you how the Magnus Effect will effect the throw.

In technical terms the upward spin of the ball is creating a low pressure zone on top and a high pressure zone on the bottom of itself.  This pressure difference on either side of the baseball causes lift.  Because of that gravity thing, the ball doesn’t actually rise, but will remain in the air for a longer period of time than that of a of a ball thrown with no spin at all.

But really that isn’t a very visual throw.  Woo, the ball goes straight.  Lets talk about something interesting like, a curveball.

The above pitch we were talking about was essentially a fastball.  A straight, no frills, fastball.  Curveball’s are more fun because the spin put on the ball acts more parallel to the ground instead of perpendicular to it.  The resulting pressure zones cause horizontal movement instead of vertical making the pitch look a hell of alot cooler.

Just to kind of add some side info here, smooth objects tend experience less of this effect than rough objects.  With a baseball it’s the threads that help create this effect.

The Kinetic Chain…

What is a kinetic chain?

Basically it’s the connection between the various parts of your body.  Just to help illustrate, take your finger and wiggle it back and forth.  Congratulations you’ve just created a kinetic chain!

So now you guys are asking, why is that a kinetic chain?  Basically think of your finger moving as a flow of energy with a start and an end.  In terms of your body this flow of energy is completely controlled by your nervous system acting upon your bones and muscles.  Your brain wants to move your finger, so it sends a signal along your nervous system that will set off a chain of events within your muscles, bones, ligaments, and tendons allowing for the action to be completed.

So in reality everything we do involves some sort of kinetic chain.

What does this have to do with baseball?

The answer is simply everything.  If it’s used in everyday life it’s obviously going to be used in baseball.  So why am I discussing it?  Well I’m here mostly to talk about applying a proper kinetic chain to the pitching motion.  I want to talk about it because the pitcher is probably the most important position on the field.

Now I’m not gonna talk about every single step involved in making a good pitch.  I will outline the greater points.

1. It starts with the legs. Some people wonder why pitchers do the crazy leg kick (some are legitimately crazy at that) at the beginning of the windup.  Well it has two important roles for the pitcher.  First it helps establish proper timing.  In other words, when my leg is here my hands, arms, etc…should be here.  Secondly it sets off the kinetic chain by shifting the bodies weight forward towards home plate.  Really if you don’t do this, you’ll be bouncing a pitch for sure.  On top of this the plant foot should land bent and than restraigten as the body continues to move forward.  Landing on a straight leg or not restraigtening the leg pretty much stops the chain.
2. Next comes the hips.  The the hips should rotate before the shoulders in the kinetic chain.  This creates a sort of “whipping” motion with the throwing arm that helps generate more velocity.  Proper hip rotation is always essential.  Not properly moving the hips (or doing anything before this point improperly for that matter) causes the body to need to over strain other parts of the body to make up for lost energy.
3. The arm and hand are the last things to go. Everything you’ve done to this point is about transferring kinetic energy into you arm and hand so that a good solid pitch can be made.  Really if you do everything with your legs and hips properly there should be very little use of the arm to make the pitch.

So to link everything together really quick.  The brain says “make the pitch.”  So it sends a signal through the nerves to the feet, where the chain kicks off.  From there various muscles and bones move beginning with the legs, than the hips, through the torso, into the shoulder, and eventually into your arms and thus your fingertips where all that energy is transferred to the baseball.  Than the baseball ends up flying through the air hitting Nick Punto in the ribs (HAHA TAKE THAT NICK PUNTO).

Again, why is this important?

Well its the threat of injury that makes proper technique important.  If it hurts to bend your knee, you use your back more to pick things up.  But if you’ve always just used your back to pick stuff up (improper lifting technique by the way) than you’ll just end up hurting your back.  Basically you use other parts of your body more than necessary when improper technique is used.  Overusing parts of your body can cause injury.  But if you properly distribute the work load through out the body to the parts designed to handle the needed effort than injury can be avoided.  This is why an injury should never be played through by a pitcher.  The violence and shear energy generated by the motion can cause a greater injury than the one being played through.  Such as if a pitcher slightly tweaks a hip.  To make up for lost strength in that muscle the pitcher will use other parts of the body more than necessary, increasing risk for greater injury or multiple ones.

So to wrap it all up…

Kinetic chains are the reason why technique in not only pitching, but everyday life is important.  Improper energy transfers through the body can put too much strain on parts of the body and thus cause an injury that may not have happened other wise.