Researchers have discovered yet another reason to hit the gym.
A new study of older adults who were at risk of developing Alzheimer’s disease claims that moderate physical activity can prevent shrinkage of the hippocampus, the area of the brain responsible for memory and spatial orientation. It is also the first part of the brain that comes under attack from the devastating disease.
"The good news is that being physically active may offer protection from the neurodegeneration associated with genetic risk for Alzheimer's disease," said Dr. J. Carson Smith, a kinesiology researcher at the University of Maryland School of Public Health
who conducted the study in a statement
"We found that physical activity has the potential to preserve the volume of the hippocampus in those with increased risk for Alzheimer's disease, which means we can possibly delay cognitive decline and the onset of dementia symptoms in these individuals,” he said.
“Physical activity interventions may be especially potent and important for this group," Smith added.
For the study, Smith and his colleagues monitored four groups of “healthy older adults ages 65-89."
The subjects all displayed "normal cognitive abilities over an 18-month period." The volume of their hippocampus also was measured using magnetic resonance imaging (MRI) at the start and finish of the 18 months.
Researchers divided the subjects into four groups, those with high or low Alzheimer’s risk and low or high levels of physical activity. Alzheimer’s risk was determined by the presence of lack of presence of an apolipoprotein called E epsilon 4 allele.
Only the group of high risk and no exercise saw a decrease in hippocampal volume over the 18 months, researchers said. All the other groups maintained hippocampal volume.
"This is the first study to look at how physical activity may impact the loss of hippocampal volume in people at genetic risk for Alzheimer's disease," said Dr. Kirk Erickson, an associate professor of psychology at the University of Pittsburgh in a statement.
"There are no other treatments shown to preserve hippocampal volume in those that may develop Alzheimer's disease,” he added.
“This study has tremendous implications for how we may intervene, prior to the development of any dementia symptoms, in older adults who are at increased genetic risk for Alzheimer's disease," Erickson said.
Smith said the study provides “additional evidence that exercise plays a protective role against cognitive decline.”
The Alzheimer’s Association
, which seeks to promote Alzheimer's care, support and research, recommends physical exercise “for maintaining good blood flow to the brain as well as to encourage new brain cells.”
“Growing evidence shows that physical exercise does not have to be strenuous or even require a major time commitment," the association said. "It is most effective when done regularly, and in combination with a brain-healthy diet, mental activity and social interaction.”
Smith said the study suggests the need for more research on how physical activity “may interact with genetics and decrease Alzheimer’s risk.”
Smith had previously shown that walking improved cognitive function in patients already experiencing decline.
He plans to do further research on the effects of exercise intervention on healthy older adults with genetic and other risk factors for developing Alzheimer’s to see how exercise might impact hippocampal volume and subsequent brain function.
According to the Alzheimer’s Foundation of America
, more than 5 million Americans suffer from the disease, a number they say will triple by 2050 as the population ages.
The findings are published in the open-access journal Frontiers in Aging Neuroscience.