■当投手的铅腿接触地面时,膝盖支撑,然后迅速伸展,启动能量转移开始骨盆和躯干旋转。
■为了研究俯仰过程中导线膝部伸展与峰值导线膝部伸展速度的关系,球速度,高中和专业投手的肘内翻扭矩。
■描述性实验室研究。
■对来自50个专业(PRO)和50个高中(HS)投手组的数据进行回顾性分析。投手在三维运动分析(480Hz)下投掷了8到12个快球。根据高或低铅膝盖伸展分为两组:PRO-high(n=18),PRO低(n=16),HS高(n=16),和HS低(n=17)。引导膝关节屈曲,导线膝部伸展速度,球速度,两组进行肘关节内翻扭矩分析。进行了回归分析,以量化所有投手的铅膝盖伸展与球速度和肘内翻扭矩之间的关联。
■脚接触时,所有投手以相似的膝盖屈曲着陆。与PRO低投手和HS低投手相比,PRO高投手和HS高投手在剩余的投球时间点中的铅膝盖伸展明显更大。PRO高投手的球速度比PRO低投手快(39.8±1.1vs39.3±1.3m/s,分别),HS高投手的球速比HS低投手快(34.1±2.6vs31.2±1.8m/s,分别)(P<.05)。与PRO低投手相比,PRO高投手的肘部内翻扭矩降低(85.3±10.7vs95.4±13.3N·m,分别);相反,HS高投手的肘内翻扭矩大于HS低投手(64.2±14.7vs56.3±12.2N·m,分别)。导线膝部伸展每增加1°,球速度增加0.47m/s(P<.001),肘部内翻扭矩增加0.27N·m(P=.025)。
■正确的铅膝盖伸展允许通过动力学链进行有效的能量转移,以产生最佳的球速并最大程度地减少专业投手的肘部内翻扭矩。相反,适当的铅膝盖伸展改善了高中投手的球速度,这并没有减少肘内翻扭矩。
■专业投手可以在肘部受到最小冲击的情况下延长其领先膝盖。在高中投手中,认识到适当的全身俯仰力学仍然优先于增加速度。
UNASSIGNED: When the lead leg of a pitcher contacts the ground, the knee braces and then rapidly extends, initiating energy transfer to begin pelvis and trunk rotation.
UNASSIGNED: To investigate the relationship of lead knee extension during the pitching delivery with peak lead knee extension velocity, ball velocity, and elbow varus torque in high school and professional pitchers.
UNASSIGNED: Descriptive laboratory study.
UNASSIGNED: Data from 50 professional (PRO) and 50 high school (HS) pitcher groups were retrospectively analyzed. Pitchers threw 8 to 12 fastballs under 3-dimensional motion analysis (480 Hz). The groups were divided according to high or low lead knee extension: PRO-high (n = 18), PRO-low (n = 16), HS-high (n = 16), and HS-low (n = 17). Lead knee flexion, lead knee extension velocity, ball velocity, and elbow varus torque were analyzed between groups. Regression analyses were performed to quantify associations between lead knee extension and ball velocity and elbow varus torque for all pitchers.
UNASSIGNED: At foot contact, all pitchers landed with similar knee flexion. PRO-high and HS-high pitchers had significantly greater lead knee extension through remaining pitching time points compared with the PRO-low and HS-low pitchers. PRO-high pitchers had faster ball velocity than PRO-low pitchers (39.8 ± 1.1 vs 39.3 ± 1.3 m/s, respectively), and HS-high pitchers had faster ball velocity than HS-low pitchers (34.1 ± 2.6 vs 31.2 ± 1.8 m/s, respectively) (P < .05). PRO-high pitchers had decreased elbow varus torque compared with PRO-low pitchers (85.3 ± 10.7 vs 95.4 ± 13.3 N·m, respectively); conversely, HS-high pitchers had greater elbow varus torque than HS-low pitchers (64.2 ± 14.7 vs 56.3 ± 12.2 N·m, respectively). For every 1° increase in lead knee extension, ball velocity increased by 0.47 m/s (P < .001) and elbow varus torque increased by 0.27 N·m (P = .025).
UNASSIGNED: Proper lead knee extension allowed efficient energy transfer through the kinetic chain to produce optimal ball velocity and minimize elbow varus torque in professional pitchers. Conversely, while proper lead knee extension improved ball velocity among high school pitchers, this did not minimize elbow varus torque.
UNASSIGNED: Professional pitchers can extend their lead knee with minimal impact at the elbow. In high school pitchers, cognizance of proper full-body pitching
mechanics remains a priority over increased velocity.