Preliminary Analysis: Moderating the Stress Perception of Collegiate Distance Runners Using Branched-Chain Amino Acids

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Exercise-induced fatigue may be caused by increases in cerebral serotonin resulting in symptoms of central fatigue (i.e. decreased mood, and increased stress and sleepiness). Branched-chain amino acid (BCAA) supplementation is one intervention that can reduce symptoms of central fatigue by competing for the tryptophan transporter reducing serotonin synthesis. Psychological monitoring tools such as The Daily Analysis of Life Demands for Athletes (DALDA) Questionnaire can be used to study symptoms of central fatigue by identifying sources of general and sport-specific stress as well as an athlete’s reaction to stressors. PURPOSE: To examine the response of BCAA on stress perception of trained collegiate distance runners using DALDA. METHODS: 8 collegiate distance runners (men n=4, women n=4) took BCAA supplement (SUP) (0.08g/kg) or placebo (PLA) daily for 6 weeks, alternating conditions week to week. Each morning athletes filled out the 34-item DALDA prior to training by selecting one of 3 answers corresponding to stress symptoms: A = “feel worse than normal”, B= “feel normal”, C= “feel better than normal”. Response ratios were generated for each of the 3 answers for each condition (SUP or PLA) by taking total number of responses for each answer over number of answers overall. Response ratios were calculated as weekly mean ± SD and MANOVA was used for analysis. The alpha criterion was set to p<0.05. RESULTS: Statistical significance was found (p<0.01), and further analyses were done to examine changes from week to week. On average, athletes reported fewer ‘A’ responses in SUP weeks than PLA weeks (SUP: 9.27% ± 2.21%; PLA: 13.46% ± 7.29%), while response percentage for ‘C’ was the same between both conditions (SUP: 11.78 ± 2.12%; PLA: 11.24% ± 2.32%). Changes from SUP weeks to PLA weeks produced noticeable changes in ‘A’ responses (e.g.: 14.36% SUP week to PLA week; -9.95% from PLA week to SUP week). CONCLUSIONS: Results from DALDA revealed a noticeable change in the stress response of the athletes from condition to condition. The athletes reported higher instances of feeling “worse than normal” during PLA weeks and fewer instances of feeling “worse than normal” during SUP weeks. These results indicate that BCAA supplementation seems to be an effective means of reducing the stress perception in these collegiate distance runners.


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