Kinematic Models For Pitch Location Metrics in Professional Baseball Pitchers

Manzi Joseph E,Dowling Brittany,Dines Joshua S,Rauck Ryan C,Roberts Nicholas,Krichevsky Spencer

doi:10.36959/987/261

Abstract

Consistency and accuracy in pitch location is paramount for professional baseball pitchers, however, the contribution of individual kinematic parameters is poorly understood. Professional baseball pitchers (n = 322) were instructed to throw 8-12 fast balls while assessed with motion-capture technology (480 Hz); pitch location was tracked by coaching staff. Elastic net regression with automated parameter optimization was utilized to model the consistency and accuracy of each pitch with a random forest model implemented to assess feature importance.

Highlights

While there have been several studies examining ball velocity as an outcome metric in baseball pitchers, [1,2,3] there is a paucity of data on the assessment of accuracy and consistency of pitch location, with only a few parameters at the distal upper extremities examined for pitch accuracy [4,5,6,7]
While a major initiating step in assessing this crucial performance metric, this study evaluated a heterogenous cohort of pitchers ranging from youth players to those at the professional level, while only assessing pitching kinematics from foot contact to ball release, not accounting for valuable differences in body positions during the windup and stride phases
Derivation of feature importance by random forest regression of pitch accuracy showed that trunk tilt at foot contact (FC) created the largest percent increase of the mean square error (6.6 % mean squared error (MSE)), followed by lead hip flexion at FC (4.2% MSE), shoulder abduction at FC (4.2% MSE), trunk tilt at ball release (BR) (3.8% MSE), and elbow flexion at maximum shoulder external rotation (MER) (Figure 2)

Summary

Introduction

While there have been several studies examining ball velocity as an outcome metric in baseball pitchers, [1,2,3] there is a paucity of data on the assessment of accuracy and consistency of pitch location, with only a few parameters at the distal upper extremities examined for pitch accuracy [4,5,6,7]. Marsh, et al [4] considered the use of vestibular feedback as a key parameter for pitch location assessments. Prior studies limit their evaluations to the distal extremity, without considering the entirety of the pitching motion or the position of the pitcher relative to the intended target. In handball, throwing consistency was determined to decrease when throwing to the contralateral side of the throwing arm, while ball velocity was found to be higher when throwing at targets on the ipsilateral side [9]

Objectives

Methods

Results

Conclusion