增補β-丙胺酸對3分鐘腳踏車衰竭測驗生理反應之影響

Abstract

目的：本研究主要探討增補β-丙胺酸對優秀運動員有氧與無氧表現之影響。方法：將24名高中以上男性優秀運動員（年齡為18.7 ± 1.6歲、身高為176.0 ± 4.0公分、體重為68.7 ± 5.9公斤），以隨機分組方式分為β-丙胺酸組（6.4 g•d-1的β-丙胺酸）與安慰劑組（6.4 g•d-1的纖維素）。在4週增補的前後，受試者進行漸增負荷運動測驗及3分鐘腳踏車衰竭測驗，以評估增補β-丙胺酸在生理反應與運動表現之影響，例如，漸增負荷運動測驗的最大攝氧量 (VO2max) 、換氣閾值 (VT) ，以及3分鐘腳踏車衰竭測驗的攝氧峰值 (VO2peak) 、結束功率 (EP) 及高於結束功率之總作功 (WEP)。並於3分鐘腳踏車衰竭測驗時採集血液，以分析血乳酸與血液pH值。結果：增補前與增補後的所有生理變項與運動表現，在兩組之間皆無顯著差異。β-丙胺酸組在增補後的最大攝氧量（增補前 vs. 增補後，55.8 ± 6.8 vs. 56.6 ± 5.5 ml•min-1•kg-1）、換氣閾值（增補前 vs. 增補後，34.1 ± 3.7 vs. 35.5 ± 4.8 ml•min-1•kg-1）、攝氧峰值（增補前 vs. 增補後，59.3 ± 7.2 vs. 57.7 ± 7.1 ml•min-1•kg-1），結束功率（增補前 vs. 增補後，257.8 ± 25.0 vs. 258.6 ± 30.7 W）與高於結束功率之總作功（增補前 vs. 增補後，10.0 ± 3.4 vs. 10.5 ± 2.00 kJ），皆未達顯著差異。然而，在增補β-丙胺酸後的血乳酸值（增補前 vs. 增補後，11.0 ± 2.8 vs. 9.3 ± 2.0 mmol•L-1）與血液pH值（增補前 vs. 增補後，7.17 ± 0.06 vs. 7.12 ± 0.05）則顯著減少。安慰劑組的所有生理變項與運動表現在增補前與增補後之間皆無顯著差異。結論：增補β-丙胺酸可能無法改善優秀運動員的有氧與無氧表現，但是能減少在3分鐘腳踏車衰竭測驗時的代謝壓力。Purpose: To investigate the effect of β-alanine supplement on the aerobic and anaerobic performance in elite athletes. Methods: Twenty-four athletes were recruited and randomly assigned to the β-alanine (6.4 g•d-1) or placebo (6.4 g•d-1 of cellulose) group. Before and after a 4 weeks supplement, participants performed the incremental cycling test and 3-min all-out cycling test to determine the effects of β-alanine on the physiological responses and performance, i.e., maximal oxygen uptake (VO2max) and ventilatory threshold (VT), peak oxygen uptake (VO2peak), end test power (EP), and work done above the EP (WEP). The blood samples were obtained during the 3-min all-out cycling test to measure the blood lactate and pH concentrations. Results: No significant differences were found on the all physiological variables or performance at pre- or post-supplementation between two groups. In the β-alanine group, no significant differences were found on the VO2max (pre vs. post, 55.8 ± 6.8 vs. 56.6 ± 5.5 ml•min-1•kg-1), VT (pre vs. post, 34.1 ± 3.7 vs. 35.5 ± 4.8 ml•min-1•kg-1), VO2peak (pre vs. post, 59.3 ± 7.2 vs. 57.7 ± 7.1 ml•min-1•kg-1), EP (pre vs. post, 257.8 ± 25.0 vs. 258.6 ± 30.7 W) and WEP (pre vs. post, 10.0 ± 3.4 vs. 10.5 ± 2.0 kJ) after supplementation. However, β-alanine supplementation significantly decreased blood lactate (pre vs. post, 11.0 ± 2.8 vs. 9.3 ± 2.0 mmol•L-1) and pH levels (pre vs. post, 7.17 ± 0.06 vs. 7.12 ± 0.05). There were no significant differences on the all physiological variables or performance in the placebo group between pre- and post-supplementation. Conclusion: β-alanine supplement might not improve the aerobic and anaerobic performance, but reduce the metabolic stress during 3-min all-out test in elite athletes.