theguerillachemist

One more reason to go with EAA(or while food complete protein) over BCAA. Exercise performance can be reduced from elevated serotonin levels. This study, in rats both exercising and sedentary, aimed to see why BCAA, which lower brain serotonin levels do not cause increases in exercise performance. BCAA, while inhibiting tryptophan uptake, also seem to inhibit synthesis of other catecholamines, as well. Catecholamines are compounds like adrenaline, dopamine, serotonin, norepinephrine, etc which are all responsible for your body’s “fight or flight” response to stress, in this case exercise. The precursors to catecholamines are the amino acids tryptophan and tyrosine(both are EAA), both of which BCAA inhibit the uptake and concentration levels in the brain. The study found that BCAA do reduce catecholamine synthesis and concentrations of tyrosine and tryptophan in both groups of rats. This may explain why BCAA do not enhance performance, even though they reduce serotonin levels which has been shown to increase performance. This effect was negated by co-administering tyrosine with BCAA. Bottom line: take EAA(or whole complete protein foods) preworkout to prevent decreases in performance associated with taking BCAA.