JAB AS A FUNCTION OF STEPPING FORWARD

• Main Authors: Chiang Tzu-Wei, 江子偉
• Other Authors: Chen Chong-You
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/57787205396068011047

碩士 === 國立臺灣體育運動大學 === 競技運動學系碩士班 === 99 === 　　The purpose of this study was to investigate the effect of various stepping forwards for jab of boxing in biomechanical approach. Eleven collegiate level boxing players, training age over five years, were recruited voluntarily as the participants for this study (mean age: 20.7 ± 1.7 years old, mean height: 173.5 ± 6.5 cm, mean weight: 66.0 ± 11.3 kg). Participant were asked to perform stand jabs, one-foot forward jabs, and two-foot forward jabs without impact five times for each movement in delivered off the lead foot and bare-handed by random order. The Vicon 3-D motion analysis system with 8 cameras (MX-F40, 250 Hz) and two Kislter force platforms (Type 9260AA, 1000 Hz) were synchronized to record the kinematical and kinematical data respectively. The Vicon Nexus system (Version 1.6.1) and Polygon Authoring Tool (Version 3.1) were used to analyze the kinematic parameters of upper extremity and ground reaction force. Repeated measure one-way ANOVA and HSD post-hoc were adopted to analyze the statistical difference with an alpha level of .05. The result showed the peak velocity of elbow and shoulder in two-foot forward jab were higher than stand jab and one-foot forward jab (ps < .05). All the jab movements were without impact to perform punching in this study and this condition made the research assumed the instant of hand velocity equal zero was the terminal position of jab. The results showed time of peak shoulder velocity and time of peak elbow velocity to terminal position had no significant difference among three jab movements in this study (ps > .05). The displacement of hand in two-foot forward jab and one-foot forward jab were larger than stand jab significantly (p < .05) during the accelerated stage. Under the movements of one-foot forward jab and two-foot forward jab, the shoulder and elbow were both showed the characteristics of accelerated again. It seems reasonable to conclude that the stepping forward created the offense effect again during the end of jab movement.