Exactly what are effective throwing mechanics?

This is the third in the series of articles in an attempt to explain why/how Barry Zito lost his fastball. Check out parts one and two.

My previous article (In the Beginning God Created Heaven and Earth… And the Ability of Man to Throw Left-Handed) extolled the virtues of being a left-handed pitcher, but there is also a “dark side.”.A left-handed pitcher’s velocity often teeters on the edge of his left-handed ability to deceive the batter. And it doesn’t take a significant velocity decrease (Zito) to nullify the advantage of being the left hander.

Left handers have had an advantage over the hitter since day one, and because of this often throw with less efficiency (never really having to learn how to throw the baseball) as compared to their right-handed counterparts. This also leads to the inability to make throwing adjustments (dial it up) because they don’t know what it is to be throwing efficiently.

Left handers who lose their velocity do continue to have an advantage over their right-handed counterparts, often as left-handed specialists. Or a select few (Jamie Moyer, Tom Glavine, Kenny Rogers) become exceptional pitchers (knowing how to get the batter out). Exceptional pitchers are rare, be they right (Greg Maddux) or left handers, simply because after one or two times through the batting order MLB hitters can make the adjustments.

Throwing a baseball: an exercise in dynamic systems, and complexity

Figure 1 The “balance” between defeating the batter/pitcher.

Diagnosing and making changes at the highest levels of throwing performance is difficult because small changes, quite often imperceptible even to the most experienced pitching coach, can have dramatic effects on performance. This same principle of small differences (changes) is echoed in the following exchange between Varos McCracken , a sabermetrics consultant, Gary Huckaby another sabermetrics consultant and Eddie Bane, the Angels’ scouting director and a former top pitching prospect himself.

Voros McCracken: “I would say that you know almost as much about what a guy’s going to do in the big leagues from his Triple-A stats as you do from his major league stats.”

Gary Huckaby: “I’ll go further and say exactly as much.”

Eddie Bane: “That doesn’t surprise me, but I don’t believe it. I won 15 games in Triple-A two years in a row. I won seven games total in the major leagues. The level of play is completely different. I led the league (Triple-A) in ERA both years. I wasn’t good enough to pitch in the major leagues.”

The human body, especially with respect to developing voluntary movement patterns, is a complex dynamic system and is subject to the principles that govern all complex dynamic systems.

“Dynamical systems theory has emerged in the movement sciences as a viable framework for modeling athletic performance. In dynamical systems theory, movement patterns emerge through generic processes of self-organization found in physical and biological systems (see Chapter 7 of Williams et al., 1999 for an overview). (Dynamical Systems Theory: a Relevant Framework for Performance-Oriented Sports Biomechanics Research)

An example of what 4 or 5 mph can do for a left hander (any pitcher), is the run that Kenny Rogers had in the playoffs of 2006 (three games, 23 innings, 0.00 ERA, 19 strikeouts). What is unfortunate is the controversy created by the alleged substance on Rogers’ glove. It’s unfortunate because the attention given to that was a convenient explanation for his dominance while ignoring the potential real reason, his ability to crank his fastball up 4-5 mph over what it had been during the season.

Chaos theory: Explaining the difference between a 90 mph and 85 mph fastball…

Dynamic systems can exhibit chaotic behavior.

“Lorenz had discovered that small changes in initial conditions produced large changes in the long-term outcome.The term chaos as used in mathematics was coined by the applied mathematician James A. Yorke. The concept means that with a complex, nonlinear system, very (infinitely) small changes in the starting conditions of a system may result in dramatically different outputs for that system.” (“Chaos Theory” http://www.crystalinks.com/chaos.html).

Retroactive Review: Ace
Looking back at some of Justin Verlander's most interesting moments.

As applied to pitching/throwing mechanics, especially at the highest levels of performance, small changes in mechanics can create significant results in terms of speed, location and/or movement. And for anyone whose job it is to work with and hopefully develop high level throwing or swing performance, the concepts/principles of dynamic systems and chaos explain much of the unexplainable.

Figure 2 above represents a mechanical simulation of throwing the ball.

Some golfers may be familiar with the “Iron Byron” swing robot that was used to test golf balls. The simulation in Figure 2 has the same attributes except that it is throwing a ball rather than swinging a golf club. The maximum ball speed in this simulation is approximately 86 mph.

Figure 3. A difference of only .01 seconds reduces speed by 8 MPH

In Figure 3, everything is the same as in Figure 2 except I have changed the length of time that the arm stays flexed. In Figure 2, I am holding the arm flexed for .02 seconds into the simulation. In Figure 3, I am holding the arm flexed for .01 seconds into the simulation. A difference of only .01 seconds. Yet this change has dramatic results on the final throwing of the ball, achieving a maximum speed of only 78 mph—an 8 mph difference from the previous simulation.

The point of these simulations is to demonstrate the effect of chaos on dynamic systems; i.e., that small changes in throwing mechanics can have dramatic effects on the results of the throw. This is something that is not fully understood or appreciated by most who engage in what is called pitching mechanics. More often than not, words such as “style” or “talent” are used by coaches and instructors to explain the unexplainable.

What constitutes effective throwing mechanics?

Before attempting to answer this question it’s important to distinguish the difference between pitching and throwing: You can throw a baseball without pitching it, but you can’t pitch a baseball without throwing it. This emphasizes that pitching is all about defeating the batter. And throwing is an integral component of the pitching process.

But throwing in itself does not constitute pitching. And this is where the water begins to muddy; i.e., the difference between pitching mechanics and throwing mechanics. In reality, there should be no difference, but more often than not what is deemed as good pitching mechanics is more about defeating the batter than it is about throwing a baseball.

Effective throwing is efficient use of the body to throw the baseball. Effective throwing is the least amount of wasted effort necessary to achieve the desired throwing result.

There are two primary components at work in throwing a baseball: strength and mechanics. The strength component can manifest itself in several ways. The good way is when the strength component works in conjunction with the mechanical component primarily in the form of maintaining what is called connection during a transfer of momentum from the larger body parts (torso) and the arm itself.

One interesting aspect of throwing is that once the momentum has been drained out of the torso, the action of the arm is far more passive and active. The arm behaves more like a whip (buggy whip “popper”) that has been driven by the body.

The negative aspect of arm strength is when the arm itself becomes the primary mechanism to throw the baseball. This can also be described as “disconnection.” Disconnection means the arm has lost its ability to receive/transform momentum from the body. A consequence of this disconnection forces the arm-shoulder complex to become more active than it should in terms of throwing a baseball. The player is trying to make up for the lack of efficient transfer of momentum by “muscling” the ball to the plate.

The kinetic chain or kinetic sequence…

All attempts to analyze the throwing process require understanding what is called the kinetic chain or kinetic sequence. When coaches and instructors are talking about using the body to throw the baseball. they are talking about the kinetic chain.

Figure 4. The Kinetic Chain

The kinetic chain/sequence is the development and transfer momentum from the larger body parts (muscle groups) such as the legs, hips and torso to the smaller body parts such as the shoulder, upper arm, forearm, hand and finally the ball. This is also described as the distal to proximal sequence, distal being the most distant point from the ball (the feet) and proximal being the closest point to the ball (the hand/fingers).

Efficiency of throwing is not the same as throwing velocity. Efficiency simply measures how effective momentum is developed and transferred from segment to segment, the ultimate destination being the ball. Velocity not only depends upon efficiency of transfer, but also the magnitude of momentum created during this process.

Another way of viewing this sequence is called the summation of velocities. That is, as the kinetic chain sequences from proximal to distal, each segment increases in velocity, as depicted in Figure 5.

Figure 5. The summation of speed principle

Rotational movement equals velocity….

There are two mechanisms for transferring momentum along the kinetic chain. The first mechanism is inter-segmental transfer due to muscle activity. The ideal situation is that when a preceding segment in the chain has reached maximum velocity, the muscles connecting this segment to the next segment such as hips to mid-torso contract at the point where the hips have reached maximum velocity.

Not only do we have the velocity of the hips to start with, but we then gain additional velocity due to the pulling (contracting) action of the muscles between the hips and the torso, which transfers the momentum of the hips to the mid-torso. This process continues up the chain but becomes less of a factor as the sequence progresses to the arm.

The second mechanism and one of the most critical in terms of players achieving maximum throwing velocity is the multiplier due to what is called the compound pendulum effect. The compound pendulum effect occurs when you have two or more masses connected in such a way as to rotate around a central axis such that momentum is transferred from one mass to the next.

Figure 6. Effects of rotation and the principle of the compound pendulum.

Figure 6 demonstrates a compound pendulum versus a rigidly connected system. The compound pendulum is the diagram on the left and is composed of a series of masses ranging from 90 pounds to five pounds connected by flexible cords.

The rigidly connected system on the left contains the same masses connected by rigid links. All else is identical between the two simulations and both systems are under the falling effect of gravity. The velocity of the most distal point (the smallest mass) is being measured frame by frame. The maximum velocity of the rigidly connected system is approximately 30 feet/second (fps). The maximum velocity of the compound pendulum (masses connected by flexible cords) is approximately 55 fps.

This simulation demonstrates several principles that are vital to maximum throwing efficiency. It demonstrates the transformation velocity effect of the compound pendulum. This velocity transformation (amplification) is a result of the physics (whipping effect) associated with rotational motion. It also emphasizes the effect of “lag” between the segments. A rigidly connected system cannot create the same final velocity as a system that allows sequential transfer momentum from segment to segment (compound pendulum).

Throwing a rotational baseball is a “two parter.”

Throwing involves a strength component and there is a mechanical component. The mechanical component is how the body accelerates the ball using momentum transfer, the kinetic chain or kinetic sequence; the same principle that results in the cracking of a whip.

The cracking of the whip when throwing a baseball is the mechanical component (the “mechanics” in “pitching mechanics”) and is totally dependent on body rotation. There are two primary sources of rotation. The most talked-about rotation is hip and shoulder rotation around what is called the transverse body plane. The second less obvious rotation is rotation in the body’s sagittal plane.

Figure 7. The body’s three planes of movement.

A cricket bowler is a very good example of rotation to throw a ball in the sagittal plane because of the restriction on the extension of the arm

“Bowling the ball is distinguished from simply throwing the ball by a strictly specified biomechanical definition. Originally, this definition said that the elbow joint must not straighten out during the bowling action. Bowlers generally hold their elbows fully extended and rotate the arm vertically about the shoulder joint to impart velocity to the ball, releasing it near the top of the arc. Flexion at the elbow was allowed, but any extension of the elbow was deemed to be a throw and would be liable to be called a no ball. This was thought to be possible only if the bowler’s elbow was originally held in a slightly flexed position. In 2005, this definition was deemed to be physically impossible by a scientific investigative commission. Biomechanical studies showed that almost all bowlers extend their elbows somewhat throughout the bowling action, because the stress of swinging the arm around hyperextends the elbow joint. A guideline was introduced to allow extensions or hyperextensions of angles up to 15 degrees before deeming the ball illegally thrown” (Wikipedia 2008)

Figure 8. Cricket bowler 100 mph

Coronal plane movement is typified by side to side movement (first base-third base) and is generally considered wasted movement with respect to throwing a baseball toward home plate.

Using the body to throw the baseball, the “bow-flex-bow.”

Athletic activity involving the generation of speed and power is typified by eccentric-concentric muscle action. The eccentric refers to a lengthening of the muscle. Concentric refers to the shortening of the muscle.

For example, to achieve a maximum standing vertical jump height, a countermovement precedes the actual jump itself. The countermovement does several things. It creates a longer distance over which to apply force. The act of going down before reversing direction generates and stores energy in connective tissue, which then can be released in the opposite direction. And it more readily prepares the muscle to reverse direction and contract more powerfully.

This same eccentric-concentric cycle can be seen in pitchers; I call it the “bow-flex-bow” cycle. This cycle describes the sequence of first bending at the waist then arching the back and then unarching the back and bending forward during the throwing cycle.

This movement can be thought of as being analogous to the cracking of a buggy whip, were first the handle of the whip is flexed backward, creating a loop in the “popper.”

Figure 9. The “buggy whip” sequence.

I first noted this phenomenon in Nolan Ryan. Later, I created a little graphic showing the cycle in the delivery of Mike Mussina.

Figure 10. Mike Musina demonstrating “bow-flex-bow” sequence

North-south vs east-west…

When the body throws the baseball, all three planes come into play and, as might be expected, their interaction can create throwing mechanics which may be subject to “interpretation.” The real issue is what body movements result in the greatest effect on throwing efficiency.

Typical pitching instruction and analysis focus more on rotation in the transverse plane than any other body movement. Hip rotation and separation are two of the most commonly used terms to describe or emphasize what the body should or should not be doing when throwing the ball. Often, arm slot is focused or discussed separately, when in reality arm slot is a product of what the body is doing.

For example Randy Johnson is a “transverse plane” thrower. His primary rotational mechanism is around the transverse horizontal plane, which creates a lower arm slot. This also may be thought of as a “east-west” thrower. Most pitchers (left or right handed) are east-west or west-east throwers.

Figure 11. Randy Johnson transverse horizontal plane thrower.

On the other extreme is the north-south thrower. North-south body action creates/promotes a higher arm slot, a more over-the-top delivery. A north-south torso action lends itself to a “teeter-totter” action of the shoulders. The lead shoulder will initially be elevated, hips leading the way, and then the front shoulder will drop and the back shoulder elevate. North-south body mechanics require a high slot for throwing efficiency. Andy Pettitte is a good example of a north-south thrower.

Figure 12. Andy Pettitte’s “North-south” mechanics.

The most efficient way to use the body to throw the baseball is to maximize the contribution from both transverse and sagittal planes. Sandy Koufax was a great example of this.

Figure 13. Sandy Koufax North-south-east-west mechanics.

It is my observation that few players are able to optimally use both planes to create and develop momentum for the arm. Of the two planes, pitchers who throw north-south (more sagittal plane) incur more velocity degradation than those who are more east-west. One potential advantage of north-south is greater strike zone latitude; the strike zone has greater tolerance for missing high-low then it does side to side.

To better demonstrate the importance of rotation, body action, and arm action, I’ve created a graphic which I call the “rotational momentum throwing plane.”
Figure 14. The rotational momentum throwing plane.

This animation depicts Tim Lincecum throwing a baseball. The flat cylinder that you see centered around his upper spine represents the momentum plane that the arm and ball wants to follow to generate and take advantage of the rotational whipping effect in throwing the ball.


Tempo is the fuel that drives the east-west-north-south engine. To my knowledge, SETPRO was the first to really emphasize the importance of tempo, to the point of developing a measurement from highest point of knee lift to release of the ball.

There is reasonable science behind this measurement. It goes along with Nolan Ryan’s belief/statement that the higher he lifted his leg, the greater his velocity. The key to this is being able to extract the momentum out of the leg lift at the right time in the delivery.

A faster tempo from highest point of the knee lift to release of the ball creates more greater momentum (mass X velocity) in the early part of the delivery, which can then be used/transferred according to the kinetic sequence.

I determined that on average hard throwers averaged approximately 22 frames on a VCR from highest point in their knee lift to the release of the ball. Average velocity throwers were somewhere around 26 frames. And the problem velocity pitchers more often than not were greater than 26 frames. Of course these relationships must be taken in conjunction with all other aspects and are not a hard and fast rule.

One interesting measurement is that Randy Johnson’s time from high knee lift to release is approximately the same as Billy Wagner‘s (about 22 frames). One would think that Randy Johnson’s time from high knee lift to release should be longer than Wagner’s because he’s almost a foot taller.

A lef -hander’s tempo correlation was the same as for right-handed pitchers; i.e., faster tempos were typically associated with greater throwing velocities. It also correlated in that left handers had a tendency to have longer tempos, which is consistent with reduced velocity.

I will repeat: Show me a left hander who throws like a right-hander and I believe that pitcher has a greater probability for success than the pitcher who throws like a left hander.

Arm action…

Arm action is one of the most important aspects of throwing, yet one of the least understood, at least from the standpoint of optimizing arm action for throwing a ball.

One way to understand arm action is to think of throwing a baseball as analogous to the buggy whip. A buggy whip has a long tapering slender handle to which is attached a “popper.” The body from feet to shoulders is the handle of the throwing buggy whip, and the arm is the popper.

Creating a loop in the popper (elbow flexion, wrist extension) is crucial to creating whipping action. The abduction of the scapular along with the upper arm in conjunction with a flexed forearm along with the wrist and hand creates the throwing loop. How this loop is created (movement pattern of the arm) has a pronounced effect on the throwing-whipping action.

There are various types of arm actions/configurations. One of the more talked about is called the inverted W, which I first described after observing the arm action of John Smoltz. Arm actions can vary from the inverted W to what is termed “slinging.” For example, Smoltz is an inverted W, while Roy Oswalt is a slinger.

There seems to be no predominant type of arm action. In my observation, left handers are subject to the same statistical distribution as right handers.

What is critical in all arm actions is creating external rotation of the shoulder. Torso rotation (transverse and sagittal) creates the change in direction necessary to cause the forearm to lay back (external rotation of the throwing shoulder). The forearm lays back as a result of its inertia; i.e., a sudden change in direction (rotation of the upper torso) leaves the forearm behind.

Another observation is that inverted W type arm actions typically lend themselves to more effective breaking balls (curveballs, cut fastballs). Slinging arm actions lend themselves more toward slider-type actions.

Initially, I felt that in inverted W had a slight advantage in terms of generating velocity. But, after 15 years of observation, I think velocity is pretty much a wash. Both types of arm actions can generate high velocities.

Glove side or front side action…

Glove side or front side action is all about symmetry. Simply stated, the glove arm and the throwing arm are mirror images of each other. Smoltz’ delivery is one of the best examples of this symmetry.

Figure 15. The lead arm/front side symmetry of John Smoltz

Some describe the action of the glove or front side as pulling the glove to the chest or moving the chest of the glove. I believe that both of these descriptions are inaccurate as to optimal use of the glove side.

The glove arm has three primary functions properly for the baseball. First is the symmetry aspect. From a nervous system standpoint, it is much simpler for the body to create equal and opposite.

Second is the momentum aspect. There is appreciable amount of momentum that can be generated in the throwing momentum plane as a result of glove side action.

And third is the completion of scapular action. During the throwing process, there is abduction of both the throwing arm and glove on scapula. The bringing back together again of the scapular is critical to optimally throwing a baseball.

Next time: Crossing the bridge; a closer look at what happened to Barry Zito’s fastball…

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The very first simulation looks like one that came from a program I’ve used before but it’s been a while and I don’t recall the name.

It has the boxes for velocity of a circle and time and from a visual perspective it looks like what I was using… can anyone tell me the name of this program

Mohamed razan
Mohamed razan

i have study more use full things in this web site ..thank you very mucth

Zita Carno
Someone has done a very good job of breaking down the components of what I have long called “The Secret”. In a nutshell (I’m thinking Brazil nut here, or perhaps the harder macadamia nut), what a pitcher has to do is drive off the lower half of the body, using the legs, the hips and the torso in one continuous—and seamless—motion to generate more power behind his/her pitches, with less effort. I learned this “Secret” a long time ago when I was watching the Yankees’ Big Three rotation and saw what they were doing and how they were doing it,… Read more »