DAYTON, Ohio -- Scientists know that a healthy diet and regular
exercise are vital to maximize brain functioning.
Regular aerobic exercise has been shown to improve reaction
time, speed of processing information, memory and attention.
Aerobic exercise has even been shown to reduce the symptoms of
depression.
Recommended levels of physical activity include at minimum three
weekly sessions of 20 minutes or more of aerobic activity that is
intense enough to elevate the heart rate, and two to three days
weekly of anaerobic activity (resistance training).
Exactly how exercise benefits the brain is still a mystery, but
it is likely that there are multiple factors at work. For example,
until relatively recently, neuroscientists believed that adults
never produced new brain cells, or neurons, the basic building
blocks of the nervous system. It was thought that we were born with
a set number of neurons that could not increase, and with age these
neurons and other brain cells died off.
We now know that not only is the brain capable of creating new
neurons, but there is evidence indicating that regular exercise
stimulates this regeneration.
Neurotransmitters are the chemical messengers of the brain.
Unfortunately, the number we produce declines as we age. However,
studies show that exercise appears to increase the production of
neurotransmitters such as norepinephrine, serotonin and dopamine.
These so-called "feel good" chemicals can have positive
effects on both thinking and mood, and the proper balance of these
chemicals is critical to maintaining a healthy brain. Other
beneficial brain chemicals that appear to be stimulated by breaking
a sweat are neutrophic factors, proteins that are responsible for
helping neurons survive, adapt and grow.
Another plus is the beneficial effect that exercise can have on
circulation. Proper blood flow is vital to both cellular waste
removal and delivery of essential nutrients responsible for proper
brain function, such as oxygen and glucose (blood sugar).
In addition to increasing overall blood flow, exercise has been
linked to the production of new blood vessels in the brain. In the
absence of regular physical activity, the brain's system of veins
and arteries can become clogged, interfering with processes
necessary to feeding and cleansing brain cells.
Lumosity.com, a leading website devoted to helping spread the
word about methods to improve brain health, cites interesting
research establishing a positive link between cardiovascular
fitness and cognition.
Dr. Arthur Kramer at the Beckman Institute at the University of
Illinois says that there may be a link between cardiovascular
fitness and the size of the hippocampus, a portion of the brain
critical for the formation of new memories.
Elderly adults who were physically fit tended to have larger
hippocampi than their less fit counterparts.
While exercise has been linked to hippocampus size and spatial
memory in rodents, this if the first study to demonstrate a similar
relationship in humans.
Although the degree varies depending on the individual, it is
well established that the hippocampus typically shrinks with age
and that this is associated with subtle but definite declines in
memory and spatial orientation.
Marjie Gilliam is a certified personal trainer and fitness
consultant. Email: marjie@ohtrainer.com. This article appeared
in the Dayton Daily News.
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