My name is Doug, and I am a baseball junkie.
It all started with an eight-year old kid and an innocent pack of Topps baseball cards. There must have been something laced into that stale piece of gum, because my formative years are nothing but a haze of cardboard stats, makeshift whiffleball fields, Mark McGwire moon shots, and heated Saberhagen-Valenzuela duels in RBI Baseball. By college I was on to the hard stuff, with fantasy baseball teams stretching as far as the eye could see, buoyed by the mass consumption of designer statistics like VORP, PAP, and EQA.
After graduation, I decided to turn my baseball addiction into a career and started climbing the ladder with a club in the Pacific Coast League. It was there that I learned that players will show up early to the ballpark just to play cards in the clubhouse, that front-office types will decorate their office walls with more posters than a college dorm room, and that gameday columnists will have three-quarters of an article written before they get to the stadium. I also learned to recognize my own shortcomings when analyzing the game, the most glaring of which involved the mystery of pitching mechanics.
Mechanical Efficiency and Pitcher Signature
Pitching mechanics form the backbone of player performance, and a pitcher's delivery will ultimately determine his velocity, movement, and command of his arsenal. There is a laundry list of pitchers who had elite talent but never approached their ceiling due to mechanical inefficiencies that blocked their ascent. Such flaws are often correctable. However a player's “signature” can present major obstacles to instruction, as some aspects of the pitcher's delivery are hard-wired to the athlete and thus borderline uncoachable. Altering a player's mechanics can be awkward in the early stages, as a pitcher re-trains his muscle coordination, but the influence of signature can make it nearly impossible to correct some issues without sacrificing effectiveness. Handedness is an extreme example of player signature—a right-handed pitcher is not about to become ambidextrous just to score a platoon advantage.
The Kinetic Chain
Pitching involves precise coordination of linear and rotational movements, and an efficient delivery will follow a very specific progression. The entire pitch sequence is executed in under 1.5 seconds, and the key to a player's success lies in his ability to repeat his motion with consistent timing. One underlying concept of the kinetic chain is that a weak link will manifest itself later in the delivery, and the coaching implication is to start at the setup and work down the chain when addressing mechanical inefficiencies. Often, the best way to fix a player's release-point consistency is to make an adjustment to his setup position, after which the rest of the components will fall into place. There are several links in the kinetic chain, and we will anchor on four major checkpoints in the delivery: set-up, maximum leg lift, foot strike, and release point.
Every play on the diamond begins with the man on the mound, and my limited understanding of pitch execution was maddening. I had pitched a bit in high school, had watched countless Triple-A hurlers from the press box, and had even scouted a number of amateur players. Yet I had no clue how a pitcher's mechanics actually contributed to his performance on the field. It was as if I had feasted at the buffet of baseball information but somehow missed out on the prime rib at the end of the table. Nothing short of addictive compulsion drove me to the National Pitching Association to work with pitching mastermind Tom House, whose scientific approach to the sport would trigger a reformation of my baseball awareness.
What had once been a jaded perception of pitching evolved into an aggressive pursuit of mound knowledge once I joined the NPA. The job provided access to the foremost experts on pitching, ranging from Hall of Fame players to renowned orthopedic surgeons, and I was trained to wear the lens of a pitching coach. Most of my time was spent consumed with the motion-capture system that we had on-site in San Diego, analyzing pitcher mechanics using the same hi-tech equipment as movie studios and video game companies. The technology allowed me to break down a delivery at 1,000 frames-per-second, to view pitches from virtually any angle, and to make strategic measurements for a bevy of functional variables. After five years spent analyzing thousands of pitches from both the bullpen and the computer, I had learned to diagnose mechanical strengths and weaknesses faster than Doogie Howser on a two-liter of Tantrum, but nothing sealed the deal quite like the experience of throwing a baseball pain-free for the first time since blowing out my shoulder as an 18-year-old.
A pitcher's set-up strategy has a ripple effect that reaches all the way to release point. Balance is an integral piece of the mechanical puzzle throughout the delivery, and efficient pitchers will begin with a balanced set-up, in an athletic position with some bend in the knees, and with the head above the athlete's center-of-mass. Signature plays a significant role in determining the ideal set-up position for each player, and though some coaches will adhere to cookie-cutter rules such as “left-handers pitch from the first-base side of the rubber,” a blanket approach can be devastating when applied to the wrong pitcher. The ideal starting position on the stripe is best determined by looking at the pitcher's back foot at release point and making a lateral adjustment so that the drag foot finishes on an imaginary centerline that runs from the middle of the rubber to home plate.
Maximum Leg Lift
Maximum leg lift is often referred to as the “top” of a delivery, and pitchers such as Cole Hamels demonstrate the strength to maintain balance along with the flexibility to sustain a high leg kick. Some pitchers will drift back toward second base and/or “stop at the top” to gather balance. However, such strategies are mechanically inefficient with respect to generating momentum. A player can harness greater kinetic energy from the set-up position, with two feet planted on the ground, while initiating movement toward the target.
Pitchers such as Felix Hernandez and Zack Greinke employ a corkscrew-like twist as they approach max leg lift and uncoil with a burst of forward momentum, though most of these pitchers need to ditch the corkscrew when pitching from the stretch due to time constraints. Tim Lincecum demonstrates that the best way to use the corkscrew is to pair it with an initial surge that is directed at the plate, combining the best of both worlds to create a tremendous stride and a deep release point. The corkscrew is also an extreme example of how a pitcher can change speeds with his delivery, as many hurlers will kick their momentum into second gear after maximum leg lift.
My greatest takeaway from the NPA was the strategic integration of objective and subjective data to improve player health and performance. Theories were driven by observations from the bullpen, and after crunching the numbers in our motion analysis system, the findings were re-applied to the field through various drills and coaching techniques. The motion-analysis stats helped to validate some of our hypotheses about pitching and to challenge some long-held beliefs in baseball. We studied the best pitchers in the game, comparing their deliveries to discover any mechanical ties that would bind baseball's most dominant arms. Our research culminated in a book that leaned on motion-analysis data to tackle the conventional wisdom of pitching, and we used photographs to visually demonstrate the mechanical similarities of five elite pitchers with superficially diverse deliveries.
A pitcher's mechanics can vary over time, and though a single evaluation might have a brief shelf-life, mechanical baselines are relatively persistent. Some of the details are easy to assess, even when consumed in small sample sizes from the convenience of a couch. Watch Brandon Morrow pitch on any given day, and odds are that his mechanics will vary widely between the stretch and the windup and that he’ll struggle to harness the timing of his delivery with a slide step and runners on base. Those issues help to explain the discrepancy between Morrow's ERA and his FIP, as well as his inability to keep the ball down when pitching from the stretch. On the other hand, we have Aroldis Chapman, who struggles to repeat his delivery regardless of the situation on the bases. Chapman's inconsistent timing of his high-octane motion leads to an erratic release point, and nobody in the stadium knows whether the next pitch will be over the plate or in Mr. Reds' ear-hole.
Defined as the moment that the landing foot comes into contact with the ground, foot strike marks the completion of the chain-link for stride. Ideally, a pitcher will avoid the imbalanced approach of Carlos Marmol by establishing a solid foundation at foot strike, with stride length cemented as the rotational elements of the delivery start to fire. King Felix has a strong stride and displays opposite-and-equal arm angles as he approaches foot strike, a technique that adds to his dynamic balance.
A mechanically-efficient pitcher will wait until after foot strike to trigger trunk rotation, allowing the hips to rotate and increasing the angle of hip-shoulder separation. Having both feet planted is essential for generating power, and one can imagine how a hitter's bat-speed would be crippled if the batter initiated his swing mid-stride, with the front foot still off the ground. Hip-shoulder separation is a key component of the velocity equation, and though the majority of major-league pitchers achieve between 40 and 60 degrees of separation, some of baseball's hardest throwers have been able to break that ceiling, including Nolan Ryan, Stephen Strasburg, and the aforementioned Mr. Chapman.
A successful release point is the consequence of the preceding elements in the kinetic chain, and the quarter-second time period between foot strike and pitch release presents the greatest opportunity for error, considering the convoluted series of actions that take place within that minuscule timeframe. The ability to repeat mechanical timing is at the heart of pitch command, and all of the gears have to click in order to produce the same release point on every pitch. A pitcher with strong balance into foot strike will have an easier time maintaining his mechanics as the throwing arm whips through the batter's visual window, with the goal of having shoulders square to the target during the “arm-cocking” phase of the delivery (a.k.a. maximum external rotation of the throwing arm), as exhibited by Clayton Kershaw.
Ideally, a pitcher will keep his head over his center-of-mass with minimal tilt of the spine as the arm accelerates forward, and strong-posture pitchers such as Roy Halladay will reap the benefits at release point to bolster pitch command. The shot of Jered Weaver provides a counterexample of a pitcher with considerable spine-tilt as he releases the baseball, though Weaver is an exception to the general rule that poor-posture pitchers lack command.
Weaver is the rare pitcher who can consistently repeat an 11 o'clock arm slot, and he finds his release-point position despite the considerable tilt to his glove side. Arm slot is a function of both mechanical efficiency and player signature, as it is the net result of a pitcher's posture combined with a biologically-driven angle of shoulder elevation (a.k.a. abduction). There is a natural trade-off that exists between height and distance at release point, as a pitcher who bends his spine to achieve a higher arm slot will cost himself distance at release, resulting in lower perceived velocity and earlier break on his pitches.
Carl Sagan said that “science is a way of thinking much more than it is a body of knowledge,” and a scientific approach to baseball requires an open mind in order to prevent previously-accepted theories from forming a barrier to discovery. To evolve as a pitching coach, I had to open my awareness to new ways of absorbing baseball, as I had been unknowingly wearing blinders from 20 years of watching the game from a single perspective. My world was rocked the first time I spent an entire ballgame focusing on just the catcher's mitt and was clued in to the functional difference between pitch command and control. The basis of the NPA approach was that Tom was willing and eager to prove himself wrong in the name of scientific progress, and half of the theories that we challenged were coaching techniques that he advocated in the 1980s.
Through the study of pitchology, we can understand the why and the how that exist behind the numbers. We can evaluate the reasons why some pitchers consistently post “lucky” BABIPs, or how “downhill plane” plays a role in the hitter-pitcher interface. “Raising Aces” is dedicated to the proposition that all pitchers are not created equal and that individual context is crucial to understanding the path of a player, including aspects of mechanics, signature, size, and stuff. The ominous world of pitching is full of theoretical sand traps, and modern research has uncovered the evidence to challenge some deep-rooted beliefs, including but not limited to:
1) Release-point height is overrated, while release-point distance is undervalued
2) The slide step may be much more harmful than it appears
3) The majority of major-league pitchers will miss the majority of their targets
4) Pitching with “effort” is not only acceptable but is often encouraged in the right context
5) Pitcher injuries rarely have an isolated cause and typically involve a combination of factors
Consider the above list a syllabus for the semester. Class dismissed.
Thank you for reading
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