Branched-chain amino acids, arginine, citrulline alleviate central fatigue after 3 simulated matches in taekwondo athletes: a randomized controlled trial

Abstract

BackgroundThe decline in cognitive performance has been shown after fatiguing exercise. Branched-chain amino acids (BCAA) have been suggested to alleviate exercise-induced central fatigue. Arginine and citrulline could remove the excess NH3 accumulation accompanied with BCAA supplementation by increasing nitric oxide biosynthesis and/or urea cycle. The purpose of this study is to investigate the effect of the combined supplementation of BCAA, arginine, and citrulline on central fatigue after three simulated matches in well-trained taekwondo athletes.MethodsIn a double-blind randomized cross-over design, 12 male taekwondo athletes performed two trials containing three simulated matches each. Each match contained three 2-min rounds of high-intensity intermittent exercise. At the end of the second match, two different supplementations were consumed. In the AA trial, the subjects ingested 0.17 g/kg BCAA, 0.05 g/kg arginine and 0.05 g/kg citrulline, while placebo was consumed in the PL trial. A validated taekwondo-specific reaction test battery was used to measure the cognitive performance after each match.ResultsThe premotor reaction time in the three single-task tests and the reaction time in the secondary task in the dual-task test were maintained in the AA trial after three matches, while they were impaired in the PL trial, resulting in significantly better performance in the AA trial. These improvements in the AA trial coincided with significantly lower plasma free tryptophan/BCAA ratio, increased NOx concentrations, and similar NH3 concentrations.ConclusionsThis study suggested that the combined supplementation could alleviate the exercise-induced central fatigue in elite athletes.

Düzenli ve Yoğun Egzersiz Yaptırılan Ratlarda Takviye Olarak Tüketilen Dallı Zincirli Amino Asitlerin Miyokard ve Koroner Damarlar Üzerine Etkisi

“…Consistent with previous data [23,24] , we found no differences between the experimental and control groups with respect to glucose, creatinine, urea, albumin, total protein, and hemoglobin levels. In addition to those, we also found WBC count, the levels of ALT, AST, ALP, amylase, lipase, the concentration of calcium, magnesium and phosphor were similar between experimental and control groups.…”

The Physiological Effects of Amino Acids Arginine and Citrulline: Is There a Basis for Development of a Beverage to Promote Endurance Performance? A Narrative Review of Orally Administered Supplements

“…Relatively recent studies have investigated the effects of both L-Arg and L-Cit supplementation on physiological responses and improving exercise performance [9,10,26,27,35,44,[46][47][48]. Exercise intensity (i.e., velocity or power output) refers to the amount of work that can be accomplished to perform a given activity, often expressed as a percentage of an individual's VO 2max , or maximal power output, both typically measured using incremental exercise testing [49].…”

“…This study, however, did not assess the potential effects of the AA in combination. In contrast, Chen et al [10] assessed running economy in 12 athletes using L-Arg and L-Cit in combination using an oral tablet. The treatment group, who received 0.05 g/kg of body weight of L-Arg/L-Cit, improved performance over two consecutive days compared with PL (p = 0.002) [10].…”

“…The consumption of different AAs as supplements are proposed to enhance athletic performance, predominately by increasing blood flow to skeletal muscle, and in turn, improving performance capacity [4,7]. Two AAs in particular, Arginine (L-Arg) and Citrulline (L-Cit), are commonly used as sporting supplements and have been studied for their inhibition of exercise-induced fatigue and vasodilatory effects which can subsequently result in enhanced performance including increased power output, reduced energy expenditure, and improved time to exhaustion [8][9][10]. Over the last few decades, numerous members of the AA family have been studied, some at great length, for their potential to modify these physiological attributes [4].…”

Low-Carbohydrate-High-Fat Diet: Can it Help Exercise Performance?

“…However, these studies used simple cognitive tests that are not related to athletic competitions. There is evidence that central fatigue may contribute to the decline in perceptual-motor performance during exhausting exercise (Chen et al, 2016; Yang et al, 2016). Whether a long-term LCHF diet would increase central fatigue and subsequently impair perceptual-motor performance in athletes is still unclear.…”