title: Branched-chain amino acids, arginine, citrulline alleviate central fatigue after 3 simulated matches in taekwondo athletes: a randomized controlled trial.
abstract: BACKGROUND
  The 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.
  
  
  METHODS
  In 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.
  
  
  RESULTS
  The 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.
  
  
  CONCLUSIONS
  This study suggested that the combined supplementation could alleviate the exercise-induced central fatigue in elite athletes.
authors.affiliation: Graduate Institute of Sport Coaching Science, Chinese Culture University, 55, Huagang Rd, Shilin District Taipei, 111 Taiwan.
authors.forename: I-Fan
authors.initials: IF
authors.lastname: Chen
authors.affiliation: Graduate Institute of Sport Coaching Science, Chinese Culture University, 55, Huagang Rd, Shilin District Taipei, 111 Taiwan.
authors.forename: Huey-June
authors.initials: HJ
authors.lastname: Wu
authors.affiliation: Department of Physical Education, National Taiwan University of Sport, 16, Sec 1, Shuan-Shih Rd, Taichung, 404 Taiwan.
authors.forename: Chung-Yu
authors.initials: CY
authors.lastname: Chen
authors.affiliation: Department of Combat Sport, National Taiwan University of Sport, 16, Sec 1, Shuan-Shih Rd, Taichung, 404 Taiwan.
authors.forename: Kuei-Ming
authors.initials: KM
authors.lastname: Chou
authors.affiliation: Sport Science Research Center, National Taiwan University of Sport, 16, Sec 1, Shuan-Shih Rd, Taichung, 404 Taiwan.
authors.forename: Chen-Kang
authors.identifier: 0000-0001-8335-6595
authors.initials: CK
authors.lastname: Chang
mesh_terms: D000597:Amino Acids, Branched-Chain; D001120:Arginine; D056352:Athletes; D054874:Athletic Performance / Q000502:physiology*; D002956:Citrulline; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D005080:Exercise Test; D006801:Humans; D008297:Male; D016139:Martial Arts / Q000502:physiology*; D018763:Muscle Fatigue / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D064133:Sports Nutritional Physiological Phenomena; D013624:Taiwan / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000597:Amino Acids, Branched-Chain; D002956:Citrulline; D001120:Arginine
keywords: Dual task; Premotor reaction time; Taekwondo; Tryptophan