Applied Physiology and Nutrition Research Group, Faculdade de Medicina FMUSP, Escola de Educação Física e Esporte, Universidade de São Paulo, Av. Melo de Moraes, 65, Butantã, São Paulo, SP, 05508-030, Brazil.
Institute of Orthopaedics and Traumatology, Faculty of Medicine FMUSP, University of São Paulo, São Paulo, Brazil.
Amino Acids. 2019 Jan;51(1):27-37. doi: 10.1007/s00726-018-2593-8. Epub 2018 Jun 15.
β-Alanine (BA) supplementation may be ergogenic during high-intensity exercise, primarily due to the buffering of hydrogen cations, although the effects of beta-alanine supplementation on strength endurance are equivocal. The aim of the study was to determine the effects of 4 weeks of beta-alanine supplementation on skeletal muscle endurance using a battery of performance tests. This study employed a parallel group, repeated measures, randomised, double-blinded and placebo-controlled design. Twenty recreationally strength-trained healthy males completed tests of isotonic strength endurance (repeated bench and leg press), along with tests of isometric and isokinetic endurance conducted using an isokinetic dynamometer. Tests were performed before and after a 4 week intervention, comprising an intake of 6.4 g day of BA (n = 9) or placebo (maltodextrin, n = 11). Time-to-exhaustion during the isometric endurance test improved by ~ 17% in the BA group (p < 0.01), while PL remained unchanged. No significant within-group differences (p > 0.1) were shown for any of the performance variables in the isokinetic test (peak torque, fatigue index, total work) nor for the total number of repetitions performed in the isotonic endurance tests (leg or bench press). Four weeks of BA supplementation (6.4 g day) improved isometric, but not isokinetic or isotonic endurance performance.
β-丙氨酸（BA）补充剂在高强度运动中可能具有增强体力的作用，主要是由于其对氢离子的缓冲作用，尽管 BA 补充对力量耐力的影响尚无定论。本研究旨在使用一系列性能测试确定 4 周 BA 补充对骨骼肌耐力的影响。本研究采用平行组、重复测量、随机、双盲和安慰剂对照设计。20 名有规律进行力量训练的健康男性完成了等张力量耐力测试（重复卧推和腿推），以及使用等动测力计进行的等长和等速耐力测试。测试在 4 周干预前后进行，包括摄入 6.4g/天的 BA（n=9）或安慰剂（麦芽糊精，n=11）。BA 组的等长耐力测试中力竭时间提高了约 17%（p<0.01），而 PL 没有变化。在等速耐力测试中，任何性能变量（峰值扭矩、疲劳指数、总功）或等张耐力测试中完成的总重复次数（腿或卧推）都没有显示出组内差异（p>0.1）。4 周的 BA 补充（6.4g/天）提高了等长耐力，但没有提高等速耐力或等张耐力。
