Abstract: Objective:To investigate the correlation of kinematic parameters and isometric muscle strength of elite pitchers, and the difference between different type pitchers. Methods: Isometric test system and three high-speed camera were used to obtained raw data in kinematics and kinetics parameters in this study. Results: (a) High correlation of the rations of peak torques between external and internal rotation, flexion and extension on shoulder joints, both high positive correlation with elbow swing velocity, release velocity of baseball and velocity of contact barrier. (b) There are many significantly differences between non-balanced type and balanced type: total pithing time, lifting knee time, stretching and treading time, and acceleration time became significantly shorter in the latter; whereas , flexion and extension amplitude of elbow joints were significantly larger in the latter. (c) There are significantly positive correlation between velocity of elbow swing and maximal angle of external abduction, whereas, negative correlation with total time of pitching; there are negative correlation between acceleration time and maximal abduction angle and positive correlation with twist angle of trunk. (d) There are significantly positive correlation between release velocity of pitching, or contact barrier and maximal abduction angle in shoulder joints. Conclusion: To date the difference between Chinese elite baseball pitcher and foreign pitcher indicated that many kinematical parameters are significant, the key point is the unbalance development of pitching arm.

Key words: Pitcher, Isometric Muscle Strength, Arm Swing Velocity, Association Study