On reason why so much hitting instruction is so bad is because many people don't understand why, or often even when, certain things happen in the swing.

As a result, they often end up confusing cause and effect.

In the best case, that leads them to focus on and teach things that would happen anyway. In the worst case, that leads them to teach the hitter to do things that interfere with the body's ability to execute a good swing.

In this piece, I discuss some of the most common misconceptions about hitting; things that many people think they know but that, in truth, they have at best only an incomplete understanding.

• The Back Knee
• Extension
• The Hands Go First
• The Role of the Hands
• Squishing the Bug

Many people see what the back knee does in the swing and, seeing that the back knees of their hitters don't do the same thing, have their hitters focus on their back knees. Usually, that means having them focus on firing, driving, or pinching their back knee down and in. Unfortunately, that usually leads to some fairly bizarre movements that don't accomplish anything productive and that don't remotely resemble the back knee movements of good hitters.

In truth, what the back knee does is largely the effect of what's going on up in the hips.

As I discuss in greater depth in my pieces on Matt Holliday's Back Leg and Back Knee Extension, the back leg and the back knee help to give the hips a base off of which they can work while the front foot is off the ground. This movement pattern is usually described as Middle-Out. Once the hips have fired and the Heel Hop movement has occurred, the base shifts to the front leg. From that point on, what happens in the back leg is simply the effect of the hips rotating and pulling the now-passive back leg around.

Albert Pujols' Lower Body Rotation

The problem with trying to fire, drive, or pinch the back knee is that it usually doesn't do anything to assist the rotation of the hips and, more often than not, actually impairs the rotation of the hips.

Extension is one of the main things that baseball color commentators focus on and talk about, especially when a hitter hits the ball well. However, and as I also discuss in my piece on the Myth of Extension in Hitting, most people don't understand when and why Extension happens.

When Extension Happens

In most cases, Extension will occur a few frames after the Point Of Contact. If you look at clips of good hitters, generally you will see Connection, and not Extension, at the Point Of Contact.

Albert Pujols at the Point Of Contact

In most cases, you will only see Extension at the Point Of Contact if the hitter has been fooled by the pitch and/or has to make a timing adjustment (e.g. to hit an off-speed pitch).

Why Extension Happens

Extension is the effect of a good swing, not the cause of a good swing.

Extension is the result of doing the correct things up to and through the Point Of Contact (POC). That includes things like maintaining Connection and achieving good Whip through the POC. If you do that then you will generate enough bat speed that your arms will be automatically pulled out into extension after the POC.

Albert Pujols' Extension

That isn't to say that Extension is something that should be ignored. Rather, a lack of Extension can be a sign of a problem. However, you have to understand that that problem is most likely occurring much farther upstream in the swing.

The other day I got the following question from a client...

Preston Peavy says the hands move first. I can't apply physics to this. Can you?

The answer to this question depends on what he means by, "The hands move first."

On the one hand, you have the concept of Connection. If the hands get trapped behind the back shoulder, then you will create a problem with Disconnection and introduce slack into the swing.

So, if he is talking about the movement of the hands relative to the back shoulder, then he's right.

Albert Pujols' Swing

However, if you look at the best swings of the best hitters, it's obvious that the hands don't move first; they aren't the first things to start rotating around into the ball. In fact, if you edit enough clips, you will find that the hands are one of the last things to start moving forward in the swing.

That of course, one reason why one of the main cues that the best hitters use is, "(Keep your) hands back." They know that, if the hands move too soon, it is impossible to hit an off-speed pitch hard.

From the standpoint of the physics of the swing, Connection is key to generating the energy that is necessary to getting good Whip. If the hands disconnect from the back shoulder, then the swing will be too arm-y and not as powerful as it would be if the swing was being powered by the entire body.

As I discuss in my piece on The Role of the Hands, the hands are not dead. Instead, they have a critical role to play in terms of maintaining the position of the barrel and the hands relative to the back shoulder. However, the hands do not do nearly as much as many people believe.

As I also discuss in greater detail my piece on Squishing the Bug, this is a common, but in my opinion not particularly helpful, cue that is supposed to promote hip rotation but, in my experience, doesn't. In fact, it is more likely to limit hip rotation than it is to improve hip rotation. That is why very few good hitters do anything that even comes close to resembling squishing the bug.

Albert Pujols Not Squishing The Bug

As the photo above shows, good hitters do not squish the bug through the POC.

Albert Pujols Appearing To Squish The Bug

I believe the whole idea of squishing the bug came from looking at swings with the naked eye and misinterpreting photos like the one above. It is easy to see how someone could believe that Albert Pujols' back foot stayed in this position throughout his swing.

However, the fact is that it did not.

Good hitters do squish the bug, but they generally do it much later on in the swing than many people teach.

The thing to notice in the clip below is when Albert Pujols squishes the bug; it's well after the POC and after he has passed through the Extension position and as the bat is coming around during his follow-through.

Albert Pujols' Lower Body Rotation

At the POC, Albert Pujols' back foot is completely up in the air.

The problem with teach hitters to squish the bug is that you will tend to hurt a hitter's hip rotation rather than helping it; by trying to squish the bug, the hitter will not be able to get their back hip all the way through, which will reduce the power of their swing.