Alexander M J, Haddow J B
Can J Appl Sport Sci. 1982 Sep;7(3):209-17.
The purposes of this study were (1) to determine the relative motions of the upper limb segments during the execution of the softball windmill pitch (2) to attempt to determine the effect of these motions on the performance of the skill. High speed motion picture film was used to calculate the kinematic parameters of the pitching arm segments during the pitch. Four highly-skilled pitchers were used as subjects. Each performed at least ten trials of the pitch, which were recorded by two motion picture cameras. The two trials with the fastest ball velocity for each of the four subjects were analyzed from a sagittal aspect only. The resulting kinematic analysis indicated that there was a definite proximal-to-distal sequence of these motions, with decelerations occurring in the proximal segments prior to release of the ball. It was concluded that one of the critical factors in highly-skilled performance of ballistic skills is the ability to decelerate such segments, which likely require very strong eccentric contractions of antagonistic muscle groups.
（1）确定在执行垒球风车式投球动作时上肢各节段的相对运动；（2）试图确定这些运动对该技能表现的影响。使用高速电影胶片来计算投球过程中投球手臂各节段的运动学参数。选取了四名技术高超的投手作为研究对象。每人至少进行十次投球试验，由两台电影摄像机进行记录。仅从矢状面分析了四名研究对象各自球速最快的两次试验。所得的运动学分析表明，这些动作存在明确的从近端到远端的顺序，在球释放之前近端节段会出现减速。得出的结论是，在弹道技能的高超表现中，关键因素之一是使这些节段减速的能力，这可能需要拮抗肌群进行非常有力的离心收缩。
