美国职业棒球大联盟的规则手册并未包含对挥棒动作的官方定义，但将挥棒定义为“尝试
击球”。由裁判决定是否出棒。通常，在裁定中考虑诸如球棒通过本垒板板的前面还是击
球手向后拉手腕等因素。一些裁判更喜欢使用“翻转手腕”标准来确定选中的挥棒动作：
如果手腕“翻转”，则会发生挥棒动作。
原文：The Major League Baseball rulebook does not contain an official definiti
on for a checked swing, but defines a swing as "an attempt to strike at the ba
ll". It is the decision of the umpire as to whether an attempt was made or not
. Generally, factors such as whether the bat passes the front of the plate or
the batter pulls their wrists back are considered in the ruling. Some umpires
prefer to use the "breaking the wrists" criterion as the method to decide a ch
ecked swing: if the wrists "rolled over", a swing occurred.
所以就真的没有明说怎麽麽样叫出棒过半啊，连大联盟都没写了。只有写裁判习惯怎么判
，没有写怎么判是对的，蔡明里是在哈囉？
不过影片还真的很难判断是否有出棒。