A new review of research on exercise and aging suggests that exercise has short- and long-term beneficial effects in improving brain function, slowing age-related cognitive decline, and reducing the risk of .
For example, one study that included men and women over age 65 showed that those who exercised for at least 15-30 minutes at a time, three times a week, were less likely to develop Alzheimer's -- even among those genetically predisposed to the disease.
Exercise Fights Aging in Brain
The results of the review were presented this week at the annual convention of the American Psychological Association in New Orleans.
In their review, researchers analyzed information from three different types of studies on exercise and aging.
The first group of studies looked at whether exercise and physical activity at certain points in a person's life can improve brain function and reduce the risk of age-related neurological diseases such as .
The results showed a significant relationship between exercise and brain function later in life and a reduced risk of dementia; these benefits appeared to last several decades.
Aerobic Training Keeps Brain Fit
The second group of studies looked at the long-term relationship between specific types of exercise or fitness training and brain function in nondemented older adults.
These studies suggested that an increased level of exercise or aerobic fitness training may improve mental processes even more than moderate activity.
In particular, one study of older adults who were randomly assigned to a walking group or a stretching and toning group for six months showed that the walkers who were aerobically active were better able to ignore distracting information during a task than those in the other group.
"Aerobically trained older adults showed increased neural activities in certain parts of the brain that involved attention and reduced activity in other parts of the brain that are sensitive to behavioral conflict," says Arthur F. Kramer, PhD, of the University of Illinois at Urbana-Champaign, in a news release.
Exercise May Slow Age-Related Changes in Brain
The third group consisted of animal studies designed to understand the molecular mechanisms behind exercise's effects on the aging brain.
These results showed that aerobic exercise and physical activity may work by moderating age-related changes in brain structure on a cellular level -- in effect, maintaining a younger-looking and younger-performing brain well into old age.
"From this review we have found that physical and aerobic exercise training can lower the risk for developing some undesirable age-related changes in cognitive and brain functions," says Kramer, "and also help the brain maintain its plasticity - [the] ability to cover one function if another starts failing later in life."