投球數對美國大聯盟先發投手後續表現的影響

The Effect of Pitch Count on Subsequent Performance in Major League Baseball Starting Pitchers

廖珮吟(Pei-Yin Liao) ； 張振崗(Chen-Kang Chang)

《身體活動與運動科學學刊》 2卷2期 (2013/12) Pp. 13-25

摘要

職業棒球投手投球數過多，可能會導致疲勞累積，影響後續場次的表現，甚至導致運動傷害，目前仍缺乏以科學方式探討投手的最適當投球負荷量。本研究以2001-2006年美國職棒大聯盟先發投手為研究對象，共520人-年，16383場比賽。以投手濫用指數（pitcher abuse point3, PAP3）計算投球負荷量，定義為【PAP3=（單場先發投球數-100）^3；若投球數小於100，則PAP3=0】，將連續三場比賽之PAP3累積量分為四組，PAP3G1（0）、PAP3G2（1-375）、PAP3G3（376-3000）、PAP3G4（＞3000）。計算前三場與後三場比賽各項數據的差異。將全部投手依每場投球數中位數分為四組不同工作量，或依投球型態分為三組（威力型、控球型、平均型），分析PAP3累積量對不同組投手各項數據比率的影響。各組別中，隨著前三場PAP3累積量增加，後三場每打席三振率、field ingindependent pitching、防禦率變差的場數比率均顯著增加，在不同工作量的投手中，後三場成績較差的比率約在相對於其每場先發投球數中位數附近開始上升；控球型與平均型投手後三場表現較差的比率約在PAPG3組開始上升，而威力型投手則約在PAPG4組+升。本研究顯示，不同工作量與投球特性的先發投手，都會受到前三場投球量過多的影響，造成後續比賽各項表現較差。不同投手似乎有不同的投球負荷上限，但是三場PAP3累積量超過3000，對各種類型投手後續比賽的表現都有負面影響。

關鍵字

先發投手 ； 投球負荷 ； 投手濫用指數

並列摘要

The performance of pitchers has significant impact of winning games in professional baseball. The increased number of pitched balls could result in the decline in subsequent performance, or even lead to injury. However, the scientific evidence for the optimal loading is still lacking. This study analyzed 16383 games from 520 starting pitcher-year from Major League Baseball between 2001 and 2006. The loading was calculated by pitcher abuse point 3, defined by PAP3=(number ofpitch-100)^3; PAP3=0 if pitch＜100. The loading was categorized into 4 groups according to the accumulated PAP3 in 3 consecutive games: PAP3G1 (0), PAP3G2 (1-375), PAP3G3 (376-3000), PAP3G4 (＞3000). The difference in performance between the previous and subsequent 3 games was calculated. The pitchers were categorized into 4 workload groups according to the median of numbers of pitches in starts, or categorized into 3 pitching types (power, finesse, average). The effect of PAP3 accumulations on the difference between the previous and subse quent performance was analyzed. In all workload and pitching type groups, the ratios of worse performance in strike out per plate appearance, fielding independent pitching, and earned run average in the subsequent 3 games were increased as the accumulations of PAP3 increase. In pitchers with different workloads, the ratios of worse performance started to increase at around the medians of their pitch counts. The ratios of worse performance started to increase in PAPG3 in finesse and average pitchers, while they were increased in PAPG4 in power pitchers. This study indicated that the increased numbers of pitches would result in poorer performance in the subsequent games in Major League Baseball starting pitchers, regardless of their workloads or pitching types. Different types of pitchers seem to be able to tolerate different workloads. However, PAP3 higher than 3000 in the previous 3 games combined would negatively affect all types of pitchers.

並列關鍵字

starting pitcher ； pitching loading ； pitcher abuse point