Have you ever wondered why exercise is recommended to improve moods and relieve stress? It is likely the effect that exercise has on increasing serotonin activity in the brain. Serotonin is important for balancing moods and has a calming effect on the brain and body.
According to studies, physical activity increases the firing rates of serotonin neurons, which results in increased release and synthesis of serotonin . Research has also found that these mood-improving effects may persist even after you have exercised due to an increase of available, or non-albumin-bound (NAB), plasma tryptophan during physical activity. Tryptophan is considered an essential amino acids and is obtained through the diet. It is also the biological precursor to serotonin. More amounts of free tryptophan means more potential serotonin that may be produced. The amount of non-albumin bound (NAB) tryptophan depends on two things: the amount of albumin and non-esterified fatty acids (NEFAs) . Research has found that aerobic plus anaerobic exercise may produce more NEFAs . NEFAs and tryptophan bind to albumin at the same site, which suggests that NEFAs can displace tryptophan at these binding sites, freeing up more tryptophan to produce more serotonin .
There is one more important factor in this serotonin-stimulating process. Branched chain amino acids (BCAAs) are found alongside tryptophan in blood plasma and use the same carrier system to pass the blood-brain barrier . Again, tryptophan can be displaced by BCAAs when competing to bind to a transporter. Exercise has been found to promote BCAA catabolism , leaving more readily transferrable tryptophan than BCAAs in the bloodstream. Thus, more tryptophan is able to bind and travel to the brain, where it may then be converted to serotonin.
While there are several natural methods to boosting serotonin levels, physical activity also has other health benefits, such as controlling weight, boosting energy, and preventing health conditions and diseases. Why not reap all of these benefits while improving your mood by exercising?
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