Glenn Jordan M, Smith Keyona, Moyen Nicole E, Binns Ashley, Gray Michelle
Human Performance Laboratory, University of Arkansas.
J Nutr Sci Vitaminol (Tokyo). 2015;61(2):161-6. doi: 10.3177/jnsv.61.161.
Longitudinal beta-alanine (BA) supplementation can improve exercise performance in males through increases in carnosine; however, females experience greater relative increases in carnosine compared to males. This potentially allows females to benefit from acute BA doses; however, effects of an acute BA dose on performance in females remain unknown. The purpose of this investigation was to evaluate how an acute dose of 1.6 g BA affects anaerobic performance in female cyclists. Twelve females (age=26.6±1.3 y) volunteered to participate in this randomized, double-blind study. All participants completed two supplement trials: 1) Placebo=34 g dextrose and 2) BA=1.6 g BA + 34 g dextrose. Thirty-minutes after supplementation, participants performed three repeated Wingate cycling tests with 2 min of active rest after each. Fatigue index, mean power, and peak power were measured during each Wingate. Lactate, heart rate, and rating of perceived exertion (RPE) were measured at rest, immediately after each Wingate, and after each active rest period. RPE significantly decreased (p<0.001) immediately following Wingates 1 and 2 and after each 2-min rest period for the BA trials; however, no differences were observed immediately after Wingate 3 (p>0.05). No significant supplementation effect was observed for any performance or physiological variable (p>0.05 for all variables). Findings suggest that an acute dose of BA (1.6 g) decreases RPE during anaerobic power activities in trained female cyclists.
长期补充β-丙氨酸（BA）可通过增加肌肽来提高男性的运动表现；然而，与男性相比，女性肌肽的相对增加幅度更大。这可能使女性能够从急性BA剂量中获益；然而，急性BA剂量对女性运动表现的影响尚不清楚。本研究的目的是评估1.6克BA的急性剂量如何影响女性自行车运动员的无氧运动表现。12名女性（年龄=26.6±1.3岁）自愿参与这项随机双盲研究。所有参与者完成了两项补充试验：1）安慰剂=34克葡萄糖和2）BA=1.6克BA+34克葡萄糖。补充后30分钟，参与者进行了三次重复的温盖特自行车测试，每次测试后有2分钟的主动休息。在每次温盖特测试期间测量疲劳指数、平均功率和峰值功率。在休息时、每次温盖特测试后立即以及每次主动休息期后测量乳酸、心率和主观用力程度（RPE）。在BA试验中，温盖特测试1和2后以及每次2分钟休息期后，RPE显著降低（p<0.001）；然而，温盖特测试3后立即未观察到差异（p>0.05）。对于任何运动表现或生理变量，均未观察到显著的补充效果（所有变量p>0.05）。研究结果表明，1.6克BA的急性剂量可降低训练有素的女性自行车运动员在无氧功率活动期间的RPE。
