Publication:

補充支鏈胺基酸與精胺酸對連續兩天籃球比賽體能與技術表現之影響

支鏈胺基酸（branched–chain amino acids, BCAA）與精胺酸（arginine, Arg）具有多重生理功能，補充BCAA可能可以降低游離色胺酸（free tryptophan）進入腦部，減少腦部血清素（serotonin）形成，進而延緩中樞疲勞；亦可能刺激胰島素分泌，促進肌肉蛋白質合成，與減少肌肉異化作用，進而減少運動後肌肉損傷。補充Arg可能可以藉由合成一氧化氮（nitric oxide），刺激血管擴張及血流量增加，進而加速代謝產物的移除；亦可能促進尿素循環，增加將氨轉換成尿素。目的：本研究目的為探討合併補充BCAA與Arg，對連續二天籃球模擬比賽之專項體能表現、投籃命中率、技術測驗及運動後肌肉損傷的影響。方法：以11名甲二級大學男子籃球校隊為研究對象，採隨機交叉設計，每次測試為期二天。於運動前1小時補充0.17 g/kg BCAA與0.04 g/kg Arg（AA測試）或安慰劑（placebo測試）。運動測試以間歇性運動型態模擬籃球比賽，上、下半場各20分鐘，中場休息15分鐘，上、下半場各2節，每節10分鐘，每節包括連續10次跳、四線折返衝刺、底線衝刺跳投、Z字防守後跳投、罰球10顆、禁區組合運動、全場組合運動、5方向投籃及6次邊線折返跑；記錄各項時間與投籃命中率，以評估體能表現與投籃技術表現。並於運動前、中場休息及運動後進行體能測驗，包括反動作跳測量（counter movement jump）與技術測驗（包括球員挑戰運球、過人、傳球、上籃、投籃等專項技術）。運動前與每節運動後詢問自覺量表（Ratings of Perceived Exertion）。於第一天運動前、後及運動後2小時，與第二天運動前、後，採取靜脈血液樣本，分析血漿肌酸激酶、乳酸脫氫酶、乳酸、氨、尿素、葡萄糖、甘油、非酯化脂肪酸、睪固酮、皮質固醇濃度。結果：AA測試於第二天第三節的籃球專項體能表現顯著快於placebo測試，第二天第四節呈現快於placebo測試的趨勢；投籃命中率與技術測驗在二測試間無顯著影響。血液生化值部分，AA測試兩天之血漿尿素濃度曲線下增加面積均呈現高於placebo測試的趨勢；而肌酸激酶、乳酸脫氫酶、乳酸、氨、葡萄糖、甘油與非酯化脂肪酸、睪固酮、皮質固醇濃度在二測試間則無顯著差異。結論：籃球選手於運動前合併補充BCAA與Arg，可能可提升連續天的比賽中，第二天運動後期的籃球專項體能表現，且補充Arg可能可以增加將運動期間產生的氨轉換成尿素；但對投籃等技術表現、能量代謝、肌肉損傷及自覺疲勞程度則無顯著影響。補充BCAA與Arg可能可以讓受測者在相同的自覺疲勞程度下，達到更佳的體能表現，但對中樞疲勞的影響機轉，仍需要進一步研究。

Branched-chain amino acids (BCAA) and arginine (Arg) have multiple physiological functions that may improve exercise performance. BCAA supplementation could suppress central fatigue by reducing the entry of free tryptophan, the precursor for serotonin, to the brain. BCAA can also stimulate insulin secretion, muscle protein synthesis, reduce muscle catabolism and reduce post-exercise skeletal muscle damage. Arg supplementation may stimulate endothelium-dependent vasodilation by increasing nitric oxide synthesis, resulted in the accelerated removal of the metabolites that may influence exercise performance. Objective: The purpose of this study was to investigate the effects of BCAA and Arg supplementation on basketball-specific physical performance, shooting, skill test and muscle damage in two consecutive days of simulated basketball games. Methods: Eleven male basketball players from a Division II university were recruited as the subjects. The study used a randomized cross-over design. Each trial contained two days. The subjects consumed either 0.17g/kg BCAA and 0.04g/kg Arg (AA trial) or placebo (placebo trial) 1 hour before the exercise test. The exercise test was a simulated basketball game with 20 min in each half and a 15-min rest in between. Each half contains 2 10-min periods with a 2-min rest in between. Each quarter includes 10 consecutive jumps, ladder suicide sprint, baseline jump shots, foul-line jump shots, free-throw shooting, key combination, full court combination, 5 directions shooting, and 6 court-width sprints. The time required to finish each tasks and the shooting percentage were recorded as the marker for basketball-specific physical performance and shooting skills, respectively. A counter movement jump test was performed before and after the simulated game, as well as at the half-time. A skill test, including dribbling, passing, layups and shooting was performed before and after the game and the time required to finish the test was recorded. The Ratings of Perceived Exertion were recorded before, at the half-time, and after the game. Blood samples were collected from the antecubital vein before, after, and 2 hours after the first simulated game, and before and after the second simulated game. The plasma concentrations of creatine kinase, lactate dehydrogenase, lactate, ammonia, urea, glucose, glycerol, non-esterified fatty acid, testosterone and cortisol were measured. Results: The time required to finish the task in AA trial was significantly decreased in the third period, while it showed a trend of decrease in the fourth period, compared to placebo trial. There was no significant difference between the 2 trials in the shooting percentage and skill test. The incremental area under the curve of the plasma urea concentration showed a trend of decrease on both days of the AA trial compared to that of placebo trial. There were no difference in the concentrations of creatine kinase, lactate dehydrogenase, lactate, ammonia, glucose, glycerol, non-esterified fatty acid, testosterone and cortisol between the 2 trials. Conclusion: The study suggested that BCAA and Arg supplementation may improve the physical performance on the second day of two consecutive days of simulated basketball games. In addition, Arg may help to increase the conversion of ammonia to urea. Nevertheless, the supplementation had no effect on skill performance, energy metabolism, muscle damage and perceived exertion. BCAA and Arg supplementation may allow the subjects to improve physical performance at the same level of perceived exertion. The mechanism through which BCAA and Arg may influence central fatigue requires further investigation.