Posted by Doug Thorburn on Wednesday, June 9, 2010 at 10:13 pm

A sold out crowd… in Washington… on a Tuesday night. Such is the impact of one Stephen Strasburg, making perhaps the most anticipated debut in the history of Major League Baseball.

This is just one of a thousand articles that will be written about the rookie right-hander this week, so allow me to differentiate this piece by turning it into a pitching mechanics primer, with fellow SDSU alum Strasburg playing the role of guinea pig.

Pitching mechanics can be a touchy subject. There is much dissension among the ranks of scouts and coaches, and many are strongly devoted to certain theories and methodologies. The power of conventional wisdom is incredibly strong in pitching circles, and there is a history of widespread resistance to anything that challenges that convention.

The statistical revolution has started to change the status quo. Technology has given us the ability to measure the game beyond the box score, by capturing real-time data for physical events on the field. Even the most stubborn of old school coaches will find it difficult to ignore the data being generated by new gadgets like Pitch f/x and high-speed motion capture. These tools provide the means to challenge conventional wisdom with hard evidence.

My personal viewpoint for pitching mechanics has been shaped by experience at the National Pitching Association (NPA), where I worked with Tom House as a pitching coach and director of the motion analysis program. I started as a grad school intern, and the NPA was the ultimate learning environment for a student of the game, providing access to elite athletes, the latest technology, and an incredible group of mentors that extends beyond the NPA Advisory Board.

 I was drawn to the NPA because of their emphasis on objective evaluation and the scientific method. The process begins with subjective experiences from the bullpen, when a player or coach notices something intriguing about a delivery. This curiosity fuels a hypothesis, which is then tested with experiments using motion capture and analysis.

The process comes full circle when an experiment reveals a new discovery about pitching mechanics, and we devise coaching techniques to integrate the new information into our instruction. The experiments start and end in the bullpen.

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Stephen Strasburg’s Mechanics

Returning to the most hyped prospect in all the land, Strasburg was pumping adrenaline in his MLB debut yesterday, showing even more electric stuff than in his nationally televised start with AAA Syracuse last week. His delivery was remarkably consistent throughout the game, with repetition of timing and mechanics from the first inning through the seventh.

From First Movement to Foot Strike

Starting at the beginning of the kinetic chain, Stephen Strasburg directs his first movement toward the plate as he lifts his front leg. This lateral move to the dish is slow and steady, and contrasts with those pitchers that drift back toward second base to start the delivery (think Daisuke Matsuzaka). Many of the top pitchers in the game start with great momentum right out of the setup position, and look more like Greg Maddux as they get into maximum leg lift.

Pitchers that stay back are usually attempting to gather their balance at the top of leg lift, but a pitcher like Strasburg has no need to halt his forward momentum in order to regain his balance. The reason is that Strasburg stays balanced throughout his delivery, with his head stabilized over center of mass, from the setup position through maximum leg lift and into release point.

Stras raises his knee toward his sternum for a relatively high leg kick. This leg lift helps to extend his stride length by keeping the landing foot off the ground a bit longer as he drives toward the plate. The style of leg kick is an aspect of personal signature, while the ability to maintain balance while executing leg lift is an element of mechanical efficiency. Strasburg displays a lower leg kick from the stretch, but he avoids the slide step and is able to maintain the timing and efficiency of his delivery with men on base.

 

Strasburg gains forward momentum after reaching maximum leg lift, surging toward the plate to further increase his stride length before his front foot strikes the ground. The goal of a long stride is to release the ball as close to the plate as possible, which acts to increase the perceived velocity of every pitch.

Strasburg achieves a very good stride, though he does have room for improvement. He could probably add another half-foot by generating more momentum from the start of his delivery. Stras does have an optimal stride direction, starting in the middle of the rubber and driving directly at the target to finish square to home plate.

Another indicator for balance is a pitcher’s arm angles as he gets into foot strike. Ideally, the glove-side arm (GS) and the pitching-side arm (PS) will mirror each other, forming opposite and equal elbow angles. Stras comes pretty close to a symmetric mirror, which is another testament to his outstanding balance. The only potential strike against Strasburg is that he displays what’s called the “inverted W,” with elbows that rise above the shoulder line prior to upper body rotation.

The “inverted W” is a source of debate, and will be covered in-depth in tomorrow’s sequel to Stras Wars.