It has long been noted that exercise can improve mental acuity and feelings of well being. Studies have shown that certain neurotransmitters are affected by exercise. Exercise can have an effect on the channels that produce serotonin, dopamine and norepinephrine and possibly others. New techniques such as microdialysis and voltammetry are now possible to measure neurotransmitters in a living animal.
Neurotransmitters are naturally existing chemicals in the human body. They are involved in the communication between the nerve cells of the body. The nerve cells control thought and movement. Nerve cells, called neurons, communicate with each other by releasing and accepting calcium and potassium. The neurotransmitters affect how much of the chemicals that excite the neurons are released or accepted. Serotonin, dopamine and norepinepherine are a type of neurotransmitter called monoamines. Exercise has an effect on the other types of neurotransmitters as well but the monoamines are studied extensively because of their affect on mood.
How Much Exercise?
Any amount of exercise shows measurable affect on neurotransmitters. Even short term exercise results in improved cognition. Those who exercise regularly show a reduction in diseases that would cause brain problems. Long runs create increases in serotonin and norepinepherine levels, which can lead to, among other things, feelings of happiness and energy. According to a study published in 2003 in "Journal of Applied Physiology," researchers found that dopamine levels were raised during prolonged exercise but the levels returned to normal quickly.
Types of Exercise
Neurotransmitter studies have varied intensity of exercise but not types of exercise. Many studies looked at the effects of running or other aerobic activity on brain neurotransmitters, but many types of exercise have not had their effects investigated. However it has been shown that a wide variety of exercises used in “exercise therapy” improve mood in depression.
The positive effects of exercise on the brain are clear: exercise causes initial increased mental clarity and over time it will reduce the rate of mental decline as well as guard against some degenerative diseases of the brain. Some of the positive effects may be caused by the impact exercise has on the neurotransmitters in the brain, but other effects may be just from increased blood flow or oxygenation rates. Inducing natural release of neurotransmitters is probably more advantageous than ingesting synthetic hormones.
Manipulating neurotransmitters can have an impact on health. Previous to our understanding of neurotransmitters there was no biochemical remedy for things such as depression or Parkinson’s (in which there is a problem with dopamine). When neurotransmitters were discovered and chemicals that could encourage them or imitate them, pharmaceutical remedies were offered. But many had unpleasant side effects. If exercise can help regulate neurotransmitters sufficiently, then those dependent on the drugs might be able to reduce their doses or discontinue them altogether.