Study looks at your brain on exercise
(TNS) Vigorous exercise boosts two brain chemicals that help people ward off severe depression, according to a new imaging study by scientists at the University of California, Davis Health System.
It has long been noted that exercise can boost mental acuity and mood. But the underlying biochemical mechanism has remained a mystery.
Researchers say the discovery could lead to new therapeutic insights, improving our understanding of brain metabolism and the chemicals that regulate emotional health.
The research also suggests a role for exercise in boosting the mood of those with major depressive disorder, often characterized by low levels of these brain chemicals. The study is published in the latest issue of The Journal of Neuroscience.
The UC Davis scientists studied 38 healthy volunteers, asking them to pedal on a stationary bicycle. The volunteers exercised strenuously for eight to 20 minutes, reaching 85 percent of their maximum heart rate.
A brain scan using powerful magnetic resonance imaging revealed increased levels of two critical neurotransmitters — glutamate and gamma-aminobutyric acid, or GABA — in the exercisers. The neurotransmitters were not elevated in a control group that did not exercise.
The most significant increases were found in a part of the brain called the anterior cingulate cortex, which regulates some cognitive functions and emotion, as well as heart rate. They also saw increases in the visual cortex, which processes visual information.
"Major depressive disorder is often characterized by depleted glutamate and GABA, which return to normal when mental health is restored," said lead author Richard Maddock, professor in the Department of Psychiatry and Behavioral Sciences, in a statement. "Our study shows that exercise activates the metabolic pathway that replenishes these neurotransmitters.
"Not every depressed person who exercises will improve, but many will," Maddock said. "It's possible that we can help identify the patients who would most benefit from an exercise prescription."
The research hints at a deleterious effect of a sedentary lifestyle on brain function, he added.
Other scientists have speculated that exercise helps the brain by increasing blood flow and oxygenation rates. A 2003 study found briefly elevated levels of different neurotransmitters, called serotonin, dopamine and norepinepherine, which are linked to feelings of happiness and energy.
The UC Davis team plans to further study how the brain uses neurochemicals during exercise and what role these chemicals may play in ultra-endurance and the sudden fatigue phenomenon during intense exercise, commonly referred to as "hitting the wall."
———
©2016 San Jose Mercury News (San Jose, Calif.)
Visit the San Jose Mercury News (San Jose, Calif.) at www.mercurynews.com
Distributed by Tribune Content Agency, LLC.