Exercise May Improve Mental Decline
Researchers are now discovering that moderate exercise can help improve cognitive functioning in people who did moderate physical activity in midlife or later. The study found that six months of high-intensity aerobic exercise improved cognitive function in people with mild cognitive impairment.
Mild cognitive impairment is a transition stage between the cognitive decline of normal aging. The disorder can affect many areas of thought and action such as language, attention, reasoning, judgment, reading and writing.
The first study included over 1,300 people who did not suffer from dementia and volunteered for the Mayo Clinic Study of Aging. Lead researcher Yonas E. Geda, M.D., M.Sc., and her team gave each person involved with the study a physical exercise questionnaire and were assessed and classified as having normal cognition (1,126) or mild cognitive impairment (198).
People who did moderate exercise of some sort such as swimming, walking, yoga, aerobics or strength training during midlife were 39 percent less likely to have mild cognitive impairment. Those who did moderate exercise later in life were 32 percent less likely to have the condition.
The researchers at the Mayo clinic believe exercise might protect people against mild cognitive impairment. They feel it is because of production of nerve-protecting compounds that increases blood flow to the brain and improves development and survival of neurons, and decreased risk of heart and blood vessel diseases.
“A second possibility is that physical exercise may be a marker for a healthy lifestyle," they write. "A subject who engages in regular physical exercise may also show the same type of discipline in dietary habits, accident prevention, adherence to preventive intervention, compliance with medical care and similar health-promoting behaviors."
A second study Laura D. Baker, Ph.D., of the University of Washington School of Medicine and Veterans Affairs Puget Sound Health Care System, Seattle, and colleagues reported that the results of their study showed cognitive improvement with moderate exercise. The study included 33 adults, average age 70, with mild cognitive impairment. Some were randomly assigned to do high-intensity aerobics for 45 to 60 minutes a day, four days a week. Others were put in a control group that had the same workout schedule, but did stretching exercises and kept their heart rate low.
Researchers found that after six months the patients who did high-intensity aerobic exercise had improved cognitive function compared to those in the control group. The beneficial effects seemed to be much better in women than in men. Researchers believe it is because the body's use of and production of insulin, glucose and the stress hormone cortisol differed in women and men.
"Aerobic exercise is a cost-effective practice that is associated with numerous physical benefits. The results of this study suggest that exercise also provides a cognitive benefit for some adults with mild cognitive impairment," the authors conclude. "Six months of a behavioral intervention involving regular intervals of increased heart rate was sufficient to improve cognitive performance for an at-risk group without the cost and adverse effects associated with most pharmaceutical therapies."