Running is good for your brain — it makes you feel good, helps relieve stress, and can foster creativity when you’re in a rut — but scientists don’t have the exact answer to how it does all this. A recent study from NYU researchers gives more insight into the importance of running on brain health.
Their findings show that running stimulates the release of two chemicals. The first is dopamine, and the second is known as brain-derived neurotrophic factor or BDNF.
“Our findings suggest that BDNF plays a key role in the long-lasting changes that occur in the brain as a result of running,” says Guendalina Bastioli, PhD, a neurobiologist at NYU Langone Health and the study’s lead author in a statement. “Not only do these results help explain why exercise makes you move, think, and feel better, they also show that these benefits continue even if you do not work out every day.”
BDNF, along with dopamine, are both released when running and have important roles in learning and memory. But how they interact together when a person is exercising is less understood. Previous research from the team had studied dopamine levels during running, but the current study shows the long-term behavior of the hormone and what it does to the brain during and after exercise.
Dozens of male mice had unlimited access to a freely rotating wheel or a locked wheel that could not move. After one month, brains slices from the mice were measured for dopamine and BDNF levels. The experiment was repeated with a new set of mice, but this time, some were genetically bred to have less BDNF than the average mouse.
Mice that were allowed to run on a wheel for 30 days had a 40% increase in dopamine release in the dorsal striatum than mice that could not exercise. The dorsal striatum is a brain area involved in movement. Overall, runners also had a 60% increase in BDNF levels than non-runners.
Even after mice experienced a week of rest with no running on the wheel, the elevated dopamine levels persisted. However, when BDNF levels were reduced, running did not lead to the added increase in dopamine.
The findings are important for people who consistently need to up their dopamine levels, such as people with Parkinson’s disease. Along with other movement disorders, treatment usually involves drugs that mimic dopamine’s effects on motor neurons.
“Our results help us understand why exercise alleviates the symptoms of Parkinson’s disease, as well as those of neuropsychiatric disorders such as depression,” says study senior author and neuroscientist Margaret Rice, PhD. “Now that we know why physical activity helps, we can explore it as a means of augmenting or even replacing the use of dopamine-enhancing drugs in these patients.”
Rice cautions that more research on humans is needed before drawing any conclusions between BDNF and dopamine in Parkinson’s disease.
The next step the team is pursuing is researching gender-based differences in BNDF and dopamine release during exercise using female mice. They will also investigate whether physically active mice have better motor skills than those who only run occasionally.
The study is published in the Journal of Neuroscience.
