Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, NC, USA.
J Int Soc Sports Nutr. 2023 Dec;20(1):2214112. doi: 10.1080/15502783.2023.2214112.
Nutrition plays a key role in training and athletic performance and dietary supplements can make a small, but potentially valuable, contribution to achieving peak athletic performance. This study is the first to investigate the effects of supplementation from the combination of BCAAs, L-citrulline, and A-GPC on exercise performance.
In this randomized, double-blind, crossover study 30 male trained cyclists (age: 43.7 ± 8.5 years) completed a 20 km cycling time trial (TT) test and a high intensity endurance cycling (HIEC) test following a 7-day supplementation period with either a supplement containing 8 g BCAAs, 6 g L-citrulline, and 300 mg A-GPC or a placebo (15 g maltodextrin). For each trial, mean values for time to completion, peak and average power output, OMNI rating of perceived exertion, and visual analogue scale (VAS) responses on perceived exertion were computed for the 20 km TT test. Mean values for time to fatigue and VAS responses on perceived exertion were computed for the HIEC test. Procedures for dietary intake and exercise patterns were implemented to achieve consistency throughout the study period.
There was a significant increase ( = .003) in peak power in the 20 km TT (354.27 ± 87.88 and 321.67 ± 63.65, for supplement and placebo trials, respectively) and a significant increase ( = .001) in time to fatigue in the HIEC test (0:19:49 ± 0:11:13 min and 0:14:33 ± 0:09:59 min, for supplement and placebo trials, respectively) with the test supplement compared to the placebo. With the test supplement, there was an average increase in TT peak power of 11% and an average increase in time to fatigue of 36.2% in the HIEC test compared to the placebo. There was no significant improvement in time to completion, average power, OMNI rating of perceived exertion, or VAS responses on perceived exertion in the TT test and no significant improvement in VAS measures of perceived exertion in the HIEC test.
The combination of BCAAs, L-citrulline, and A-GPC used in this study improves cycling performance and may be useful for individuals seeking to improve athletic performance, particularly in disciplines requiring lower body muscular strength and endurance.
营养在训练和运动表现中起着关键作用，膳食补充剂可以对达到最佳运动表现做出微小但有潜在价值的贡献。本研究首次调查了补充支链氨基酸（BCAAs）、L-瓜氨酸和 A-GPC 的组合对运动表现的影响。
在这项随机、双盲、交叉研究中，30 名男性训练有素的自行车手（年龄：43.7±8.5 岁）在进行为期 7 天的补充后，完成了 20 公里自行车计时赛（TT）测试和高强度耐力自行车（HIEC）测试，补充剂中含有 8 克支链氨基酸、6 克 L-瓜氨酸和 300 毫克 A-GPC，或安慰剂（15 克麦芽糊精）。对于每个试验，计算了 20 公里 TT 测试中完成时间、峰值和平均功率输出、OMNI 感知用力等级和感知用力的视觉模拟量表（VAS）反应的平均值。计算了 HIEC 测试中疲劳时间和感知用力的 VAS 反应的平均值。实施了饮食摄入和运动模式的程序，以在整个研究期间保持一致性。
在 20 公里 TT 中，峰值功率有显著增加（ = .003）（补充剂试验为 354.27±87.88，安慰剂试验为 321.67±63.65），HIEC 测试中疲劳时间有显著增加（ = .001）（补充剂试验为 0:19:49±0:11:13 分钟，安慰剂试验为 0:14:33±0:09:59 分钟），与安慰剂相比，试验补充剂有显著改善。与安慰剂相比，使用试验补充剂，TT 峰值功率平均增加 11%，HIEC 测试中疲劳时间平均增加 36.2%。在 TT 测试中，完成时间、平均功率、OMNI 感知用力等级或感知用力的 VAS 反应没有显著改善，在 HIEC 测试中，感知用力的 VAS 测量也没有显著改善。
本研究中使用的 BCAAs、L-瓜氨酸和 A-GPC 的组合提高了自行车运动表现，可能对寻求提高运动表现的个体有用，特别是在需要下肢肌肉力量和耐力的运动项目中。
