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For years, pitchers and their inherent pitching mechanics were based off conventional wisdom.

Guys who had been around the game for a while were teaching kids, young adults, and even professional baseball players concepts that really had no scientific backing.

That is really scary.

Pitching consists of a lot of intricate movements. Often times these things happen so quickly that they are pretty hard to pick up with the naked eye.

So how did that make conventional wisdom accurate?

Considering the many nuances that are individual to each pitcher, such as arm swing, and leg kick, only highlights the disconnect.

Conventional wisdom was and continues to be quite a headscratcher.

There are also things that are inevitably different, such as stride and release point.
Stride length due to pitcher height and release point due to the flexibility of a pitcher’s upper body.

If you have not noticed yet, each pitcher has his own way of throwing a baseball.

There should not be a cookie cutter approach to pitching mechanics because each body is different, and each pitcher has his own way of doing things, and the goal should be to maximize his potential, while minimizing chance of injury.

One area that a lot of younger pitchers miss out on due to conventional wisdom is hip to shoulder separation.

What is Hip to Shoulder Separation?

Let’s use a common rubber band analogy for hip to shoulder separation to help explain the concept.

The more you stretch a rubber band the harder you can fling the rubber band into the air. (Although the more you stretch the rubber band the more likely it is to break, under lesser loads, but that is a fatigue analogy for discussion at a later time).

More stretch equals more stored up (potential) energy that can go through the baseball (kinetic energy).

This concept can be related to torque in baseball pitching mechanics language. As shoulder separates from the hip in the windup, potential energy is being stored. The energy is then released and creates torque around the hips and core.

I’ll touch more on this later.

To keep things consistent here, I refer to the anatomy of the pitcher throughout their pitching mechanics as the kinetic chain.

Every baseball pitcher starts his pitching motion with his feet, and it ends when the ball leaves his hand and he follows through with the pitch.

The whole time the body is producing or storing energy in an effort to put as much force through the baseball as possible, that way it can be thrown faster or with more force. (Newton’s law of every action has an equal and opposite reaction comes to mind).

There are many ways to increase (or decrease) this energy build up, but a big portion comes in the form of hip to shoulder separation and creating as much of a “stretch” as possible.

Let’s have the guys over at Sports Science break this concept down further for you.

Before video cameras and advanced technology, hip and shoulder separation was overlooked because there was no easy way to break down a pitcher’s mechanics in slow motion.

The clip above shows how the “stretch” of the rubber band correlates with the loading that creates torque. The upper body is “twisted” when the arms are horizontal. The rubber band is then released, and the upper body snaps into action with the core and legs.

To take a quote from the Tom House, one of the gurus of pitching mechanics in the above video:

80% of velocity comes from hip to shoulder separation- Tom House.

Yeah, we should definitely pay attention to hip to shoulder separation.

As an aside, one small thing that often goes unnoticed in pitching mechanics is the landing foot of a pitcher. Ricky Mears from Innings Pitched talked about that extensively here.

This has a lot more to do with their mechanical efficiency than most people think.

If the front foot is too open at landing point, then it puts a lot of torque on the knee and forces the hips and shoulders to open up too early. The pitcher will then get very rotational.

Pitchers that over rotate too early, often have command issues because it’s hard to repeat their mechanics over, and over, and over again.

Having a closed front foot can block the hips from being able to fully open up, hindering the separation that can be created from the hip and shoulder.

If you refer to the picture of Nolan Ryan later in this post, his front foot is slightly closed but in line with home plate while his hips are open to the plate and his shoulders are closed off.

As arguably the best pitcher of all time, I think this is a very good example.

I digress.

Scapular Pinch and Hip to Shoulder Separation

Any pitcher should be able to create around 35-40 degrees of hip to shoulder separation. The elite baseball pitchers create 40 to 60 degrees of hip to shoulder separation.

The hips open up and fire before the core engages, and then the shoulders and arm follow. So the hips need to be strong, mobile, and steady to keep everything else in line and on track.

However, strength is not the only requirement, which is why you sometimes see tall lanky, flexible guys throw hard.

To create separation between the hips and the shoulders a certain level of flexibility is required. While some guys are born with a high level of flexibility, most are not, so it is something a pitcher should consciously work on.

As you may have inferred, limited flexibility will hinder the amount of separation possible, which can lead to diminished velocity. Some baseball pitchers try to overcome lack of flexibility with brute strength, but that can lead to injury.

There are many exercises that can be used to increase hip mobility and strength, such as lunges, squats, or leg extensions. The pitcher should add strengthening exercises to their daily stretching routine, pregame ritual or practice plan.

Let’s talk some examples of hip to shoulder separation, beyond the video from Sports Science above.

Nolan Ryan, Texas Rangers Hip to Shoulder Separation

Nolan Ryan- Hip to Shoulder Separation

Note that Nolan Ryan’s core is engaged. His belt buckle is pointing towards home plate, with his throwing arm extended backwards and separated from the hip.

His engaged core helps him keep his weight back and for him to remain balanced. These movements allow the pitcher to store (potential) energy that will be used after the full scapular load develops.

Also note that he has a long stride and his front foot is slightly closed and points towards a right handed batter.

You may be scratching your head right about now (as we introduced a couple new terms), but trust me it is simpler than it sounds.

Potential energy is being generated as the throwing arm is extended backwards (creating hip to shoulder separation). This loading sequence of the upper body is often referred to as the scapular pinch, since the shoulder blades “pinch” together in this sequence.

After the scapular pinch, the baseball pitcher unloads the stored potential energy in the hips. This transfers the potential energy from the hips into kinetic energy, as the hips rotate. The upper body then releases from its scapular pinch and the gap created by the hip to shoulder separation closes.

This creates a double loading scenario where the hips are loaded due to front foot strike and the upper body is loaded due to hip to shoulder separation and scapular pinch. That’s a lot of potential energy to be released.

Let’s examine a few additional images, to hammer home the concept of hip to shoulder separation and scapular pinch.

Aroldis Chapman, Hip to Shoulder Separation

Aroldis Chapman, Hip to Shoulder Separation PHOTO: CHRIS SWEDA/CHICAGO TRIBUNE

Similar to Nolan Ryan, Chapman’s belt buckle is pointing towards home plate before his front leg lands. His back shoulder cannot be seen in the photo due to so much separation from his hips, a big source of his ridiculous velocity.

His shoulder blades, on his back, are pinched together and his core is starting to engage, getting ready to pull his arm through.

Cole Hamels, Texas Rangers Hip to Shoulder Separation

Cole Hamels- Hip to Shoulder Separation

Similar to the above images, Cole Hamels’ belt is pointing towards home plate. His back shoulder also cannot be seen in the photo due to large separation from his hips.

Let’s dig back into our rubber band analogy once again.

The rubber band when fully stretch is at its peak potential energy, waiting to be let go, to transfer the potential energy into kinetic energy.

Now let’s relate this to the human body.

The upper body is “twisted” shoulder separated from the hips, potential energy.

The hips start to open and the core engages pulling the arm through, potential energy from hips transfers to upper body inform of kinetic energy.

The energy generated from the hips works together with the stored potential energy from the scapular pinch and shoulder separation. The combined energy transfers and becomes kinetic energy that is released into the baseball.

Science is fun!

As you can see, more separation between the hip and shoulder is better. This is due to the possibility of creating more potential energy in the upper half that works in tandem with the lower half of the body.

Importance of the Core and Shoulders

The core of the body engages at the tail end of the scapular pinch, when the shoulder is farthest from the hips.

The hips start to rotate and the core engages. The legs and core of the body attempt to transfer all the potential energy from the double loading scenario above, into kinetic energy.

In the images above, you can see the core starting to engage at the point of maximum hip to shoulder separation.

The core is important and helps pull the throwing arm forward.

Some pitchers get oblique strains due to improper stretch or strength training of the core muscles. Other baseball pitchers have poor glove side action due to improper engagement of the core after the scapular pinch.

David Price Poor Glove Side Action and Pitching Mechanics

David Price Poor Glove Side Action and Pitching Mechanics

Many athletes utilize the medicine ball to train the core for mobility and strength. Some common examples of medicine ball training regimes include, side to side tosses, slamming the ball into the ground from overhead, and rotationally throwing it for distance.

Let’s move up the kinetic chain to the shoulders.

As the hips are open, the shoulders should be closed off with even a little tilt. Derek Johnson talks about this in his book, “The Complete Guide to Pitching”.  Ricky Mears at Innings Pitched considers the book a must read for any aspiring pitcher or coach.

Keeping the weight and center of gravity back towards the rubber will allow more energy to be created and stored that can later be put through the baseball on the throw.

Shoulders can be considered subjective because the angle created depends heavily on hip and core mobility.

The muscles in the chest, upper back, and shoulders are important focal points here but the prime emphasis is still on the hips and core.

Inflexible hips and tight core will minimize movement in the shoulders, which in return hurts separation of the arm.

If you ever had the privilege of doing yoga, you know that the core can inhibit you from opening up your shoulders in almost every move.

Poor flexibility will often result in diminished velocity.

Hip Shoulder Separation Conclusion

Regardless of your skill or playing level, hip and shoulder separation is important to see on the mound.

It correlates highly with velocity and also helps create better timing; which contributes to overall arm health.

If you are interested in analyzing it yourself, the easiest way to analyze your mechanics is through film work.

You don’t need an expensive video camera either. In most cases a smart phone in slow motion mode can get the footage you need to analyze yourself.

Send Ricky Mears of Innings Pitched a tweet over on Twitter or leave me a comment here, if you would like some help analyzing your hip to shoulder separation.