Serotonin is a brain chemical that helps move messages throughout the nervous system. This neurotransmitter performs many functions, including regulating mood, appetite and the sleep/wake cycle. Consuming certain foods helps stimulate the production of serotonin in the brain—and so does exercise.
Serotonin and Depression
Approximately 75 percent of this chemical is located in cells of the gut, where it regulates intestinal movements. The rest is synthesized in neurons of the brain; it's here that serotonin influences mood. High levels are associated with an elevated mood while low levels are associated with depression. Though many neurotransmitters work in harmony to influence mood, serotonin is one of the most important. Its levels are influenced by external factors, such as sunlight, diet and exercise.
Influence of Exercise on Serotonin
According to the National Institute for Health and Clinical Excellence, of the United Kingdom, exercise increases brain serotonin function in humans. A study published in Neuropsychopharmacology revealed that there are two mechanisms by which physical activity increases brain serotonin. First, motor activity increases the rate and frequency at which serotonin is "fired" within the brain, resulting in an increase in both the release and synthesis of it. Secondly, regular exercise increases the level of tryptophan in the brain (an amino acid used to manufacture serotonin). The exact mechanism is not clearly understood; however, it is clear that aerobic exercise improves mood through increasing brain serotonin levels.
Yoga, Pilates, weight training and stretching are fantastic exercises for strength, flexibility and stress management. However, aerobic exercise, including walking, running, biking, swimming (among others) seem to be the most effective at increasing serotonin synthesis in the brain. Have you ever heard of a "runner's high?" Well, it describes the effect of "feel good" neurotransmitter chemicals released during exercise that elevate mood during and after a workout. The optimal amount of exercise needed to enhance serotonin synthesis in the brain is 3 hours weekly, or 30 minutes most days of the week. Thirty minute sessions may be divided throughout the day in three 10-minute increments.
- Neuropsychopharmacology; Activity of serotonergic neurons in behaving animals; BL Jacobs and CA Fornal; 1999.
- Behav Pharmacol; In vivo measurement of extracellular serotonin in the ventral hippocampus during treadmill running; WM Wilson and CA Marsden; 1996.
- J Psychiatry Neurosci; How to increase serotonin in the human brain without drugs; Simon Young; November 2007.