Context: Improper baseball pitching biomechanics are associated with increased stresses on the throwing elbow and shoulder as well as an increased risk of injury. Evidence Acquisition: Previous studies quantifying pitching kinematics and kinetics were reviewed. Study Design: Clinical review. Level of Evidence: Level 5. Results: At the instant of lead foot contact, the elbow should be flexed approximately 90° with the shoulder at about 90° abduction, 20° horizontal abduction, and 45° external rotation. The stride length should be about 85% of the pitcher’s height with the lead foot in a slightly closed position. The pelvis should be rotated slightly open toward home plate with the upper torso in line with the pitching direction. Improper shoulder external rotation at foot contact is associated with increased elbow and shoulder torques and forces and may be corrected by changing the stride length and/or arm path. From foot contact to maximum shoulder external rotation to ball release, the pitcher should demonstrate a kinematic chain of lead knee extension, pelvis rotation, upper trunk rotation, elbow extension, and shoulder internal rotation. The lead knee should be flexed about 45° at foot contact and 30° at ball release. Corrective strategies for insufficient knee extension may involve technical issues (stride length, lead foot position, lead foot orientation) and/or strength and conditioning of the lower body. Improper pelvis and upper trunk rotation often indicate the need for core strength and flexibility. Maximum shoulder external rotation should be about 170°. Insufficient external rotation leads to low shoulder internal rotation velocity and low ball velocity. Deviation from 90° abduction decreases the ability to achieve maximum external rotation, increases elbow torque, and decreases the dynamic stability in the glenohumeral joint. Conclusion: Improved pitching biomechanics can increase performance and reduce risk of injury. SORT: Level C.

Background: Bat velocity, attack angle, and vertical angle are common variables that coaches and players want to evaluate during their baseball or softball swing. Objective: The purpose of this study was to investigate and validate a baseball bat handle sensor against motion capture using recreational baseball and softball athletes for bat velocity, attack angle, and vertical angle. Methods: This single visit cross-sectional experimental design study utilized eighteen recreational baseball and softball players (ten males and eight females, age: 20.70 ± 1.69 years, height: 170.74 ± 5.69 cm, weight: 77.97 ± 12.30 kg) were recruited. Bat velocity, attack angle, and vertical angle from the bat handle sensor and 12-camera motion capture system were collected and compared using a two-tailed paired t-test. Results: Differences were statistically significant, showing that 95% of the time, the bat handle sensor overestimated the bat velocity by 1.92 to 2.77 m/s, underestimated the attack angle by -3.46 to -1.96º, and overestimated the vertical angle by 1.64 to 3.21º, compared to the motion capture system. Conclusion: The bat velocity and vertical angle were overestimated, while the attack angle was underestimated by the bat sensor. The information presented in this study can be viable information for coaches and players when utilizing the baseball bat handle sensor technology for training, practice, or in-game situations.

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In order to successfully hit a baseball, hitters must utilize a series of preparatory movements (swing phases) which include shifting their body weight, stepping, landing, and swinging. The purpose of this study was to examine the differences between start times for swing phases (shifting, stepping, landing, and swinging)for currently active baseball players. Participants (n = 12) were all current collegiate baseball athletes. Retroreflective markers, surface electromyography (EMG) and two force platforms were utilized to complete a swing analysis. Each participant completed five swinging trials off a tee. All dependent variables were compared using a repeated measures 1×4 ANOVA with LSD post hoc comparison (p < 0.05) if necessary. The results demonstrated that the participants started the swing phases in a statistically significant sequence of shifting, stepping, landing, and swinging. The ability of the athletes to start the swing phases in this sequential order may be advantageous to regulate spatial parameters of their swing and provide more time to generate power. These results allow for coaches to better understand how to instruct their athletes to be successful at the plate.