咖啡因攝取對高中棒球投手投球表現之影響:以臺北縣立秀峰高中為例

Abstract

目的：本研究的目的是探討臺灣高中棒球投手攝取咖啡因，對於肌肉肌電表現、投球速度、準度及運動自覺程度（rating of perceived exertion, RPE）的影響。方法：受試者為10位現任正規高中棒球投手（年齡：16.7±1歲、身高：174.3±4.3公分、體重：72.5±7.3公斤、投手球齡：2.8±1.3年），採重複量數的雙盲實驗設計，以平衡次序原則分別攝取5mg/kg的咖啡因或安慰劑，60分鐘後進行20顆正常投球施測，兩次測驗間之排空期為一星期。以重複量數t考驗（t-test）分析四種變項：肌電、速度、準度及本體自覺程度（RPE）的影響，顯著水準為p＜.05。結果：肱三頭肌肌電表現：咖啡因組（0.45V）與安慰劑組（0.42V）；屈腕肌肌電表現：咖啡因組（0.23V）、安慰劑組（0.23）；投球速度：咖啡因組（116.4km/hr）、安慰劑組（113.9km/hr）；投球準度：咖啡因組（23.6％）、安慰劑組（28％）；RPE值：咖啡因組（13.5）、安慰劑組（14.1），以上施測結果皆無顯著差異。結論：咖啡因攝取對臺灣高中棒球投手投球表現不會有顯著影響，本研究因只測量為大約20球（平均一局之投球數），只能探討知咖啡因攝取對於出場短暫投球量較低之投手無顯著影響，但對於投球時間較長與量較高之投手仍待進步之研究。

Purpose：To investigate the effects of caffeine ingestion on high school baseball pitchers’ muscle action potential, pitching speed, accuracy and rating of perceived exertion（RPE）in Taiwan. Methods：Subjects were 10 high school baseball pitchers.(age:16.7±1 yr, height:174.3±4.3 cm, weight:72.5±7.3 kg, years of pitching:2.8±1.3 yr), A double-blind repeated-measures design was used for the experiment. The testing order was counter-balanced. Placebo or caffeine (5mg/kg) capsules were ingested 60 minutes before 20 pitching tests with a 7-day washout period between tests. The effects of treatment were evaluated using a repeated-measures t-test to compare：muscle action potential, pitching speed, accuracy and RPE. A p values of less than .05 were considered to be statistically significant. Results：Muscle action potential of triceps：caffeine (0.45V), placebo (0.42V)；muscle action potential of wrist flexor：caffeine (0.23V), placebo (0.23V)；pitching speed：caffeine (116.4km/hr), placebo (113.9km/hr)；pitching accuracy：caffeine (23.6％), placebo (28％)；RPE：ingested caffeine (13.5), ingested placebo (14.1), the results of all the above tests were no significantly difference between groups. Conclusion：The effects of caffeine ingestion on pitching performance of senior high school baseball pitchers in Taiwan was no significantly different. The pitching number is about 20 pitches (the average pitching number of one inning). We can only infer that the caffeine consumption doesn`t have significantly influence on whose pitching number is lower than average. But for those whose pitching number is larger than average, we still need to go for further research.