Differences in Rotational Kinetics and Kinematics for Professional Baseball Pitchers With Higher Versus Lower Pitch Velocities

Abstract

Pitch velocity (PV) is important for pitching success, and the pelvis and trunk likely influence pitch performance. The purposes of this study were to examine the differences in pelvis and trunk kinetics and kinematics in professional baseball pitchers who throw at lower versus higher velocities (HVPs) and to examine the relationships among pelvis and trunk kinetics and kinematics and PV during each phase of the pitch delivery. The pitch velocity, pelvis and trunk peak angular velocities, kinetic energies and torques, and elbow and shoulder loads were compared among HVPs (n = 71; PV ≥ 40.2 m/s) and lower velocities pitchers (n = 78; PV < 39.8 m/s), as were trunk and pelvis rotation, flexion, and obliquity among 7 phases of the pitching delivery. Relationships among the kinetic and kinematic variables and PVs were examined. Higher velocity pitchers achieved greater upper trunk rotation at hand separation (+7.2°, P < .001) and elbow extension (+5.81°, P = .002) and were able to generate greater upper trunk angular velocities (+36.6 m/s, P = .01) compared with lower velocity pitcher. Trunk angular velocity (r = .29) and upper trunk rotation at hand separation (r = .18) and foot contact (r = .17) were weakly related to PV. Therefore, HVPs rotate their upper trunk to a greater degree during the early phases of the pitching motion and subsequently generate greater trunk angular velocities and PV.

Kinematic and kinetic comparison between American and Japanese collegiate pitchers

“…Only one other study has investigated rotational kinetic energy in pitchers and found no difference between high velocity and low velocity professional pitchers. 20 In the current study, trunk KE was reported 35−39 J which was similar to Luera et al's 20 values of 36 J. However, our values were less for pelvis KE (31−33 J) compared to the aforementioned study (36−39 J).…”

Kinematic Models For Pitch Location Metrics in Professional Baseball Pitchers

“…Motus Global (Rockville Centre, NY, USA) de-identified all data prior to distribution and study guidelines were approved by the Institutional Review Board at XX. Pitching evaluations were performed as previously described [13]. Pitchers reported to the test site where they signed a waiver of privacy and provided consent.…”

“…All data processing to develop full body kinematics and throwing arm kinetics was performed in custom MATLAB scripts (The Mathworks, Natick, MA , USA) [13]. A 14 Hz Butterworth low-pass filter was used to filter the motion data from each marker.…”

“…A 14 Hz Butterworth low-pass filter was used to filter the motion data from each marker. Total body segment and joint positions were used to establish key time points of the pitch: maximum knee height (MKH), hand separation (HS), elbow extension (EE), foot contact (FC), maximum shoulder external rotation (MER), ball release (BR), and maximum shoulder internal rotation (MIR) [14,15]. FC was identified as the first frame when the lead toe or heel in the Z axis reached the minimum point of contact.…”

“…All full body kinematics used in this analysis are as previously described [14,15]. Trunk tilt was calculated as an angle from the trunk line (right to left shoulder markers) to the pelvis line (right to left anterior superior iliac spine (ASIS)) in the coronal plane, where negative tilt was towards the glove hand (Figure 1A).…”