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.
Exercise, Serotonin, and Mood
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 acid and is obtained through the diet. It is also the biological precursor to serotonin. More amounts of free tryptophan mean more potential for serotonin to 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 .
Exercise Breaks Down Barriers to Serotonin Synthesis
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 transferable 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 and boosting energy. Why not reap all of these benefits while improving your mood by exercising?
Not Feeling the Mood-boosting Effect of Exercise?
While research has shown exercise can increase serotonin levels, tryptophan is required as the precursor. However, tryptophan can be depleted by repeated stress or diverted to the kynurenine pathway if inflammation is present, making it hard to produce enough serotonin to boost your mood. Neurotransmitter testing in urine can identify depleted serotonin levels. If they are low, additional tryptophan or the more immediate serotonin precursor 5-hydroxytryptophan (5-HTP) can be taken as a supplement to help support healthy serotonin levels.
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Clinical Support Specialist at Sanesco International, Inc.
Annabelle Bennett is a Clinical Support Specialist at Sanesco. She is a recent Clemson University alumnus with a Bachelor of Science in Biological Sciences. She enjoys getting her dopamine boosts from coffee, the beach, and her two little dogs.