Using Sensors for Player Development: Assessing Biomechanical Factors Related to Pitch Command and Velocity

Abstract

Pitching biomechanical research is highly focused on injury prevention with little attention to how biomechanical data can facilitate skill development. The overall purpose of this study was to explore how sensor-derived segment kinematics and timing relate to command and ball velocity during baseball pitching. We used a cross-sectional design to analyze a series of pitches thrown from 10 collegiate baseball pitchers. We collected biomechanical data from six inertial sensors, subjective command from the pitchers, and ball velocity from a radar device. Stepwise regression analyses were used to explore biomechanical variables associated with command for all pitches and ball velocity for fastballs only. We found that only peak forearm linear acceleration was significantly associated with command, whereas several segment kinematic measures were significantly associated with ball velocity. Our results suggest that different biomechanical variables are linked to specific pithing skills. Our findings suggest that end-effector (forearm) movement is more important for pitch command, whereas proximal-to-distal (pelvis, trunk, upper arm, forearm) segmental movement is important for ball velocity.

Keywords: accelerometers; kinematics; pitching; skill; throwing; velocity; wearables.

Figure 1

Sensor placement of six inertial sensors (Opal, APDM, Inc., Portland, OR, USA) affixed using straps or adhesive tape.

Figure 2

Pitch locations for left-hand pitchers (LHP) and right-hand pitchers (RHP). Pitch locations are shown from the pitcher’s perspective. Three intended locations (box, arm-side, and glove-side) are shown separately for LHPs and RHPs. The square represents the strike zone; coordinates to construct were taken from Pavlidis, Judge, & Long, 2017 [10]. Points (n = 1) where the strike Y was greater than 25 were removed for better visualization. This point remained in data analysis.