July 31, 2010
Ongoing physical activity has been linked to a longer life and all kinds of benefits for the body, including less heart disease, fewer falls and broken bones, greater lung function and a trimmer physique. Now, two new studies provide further evidence that regular exercise may be good for staying mentally sharp into old age. Resistance training, in which the body works against weight, may have particular benefits for the brain. The studies were published in the Archives of Internal Medicine, one of the medical journals from the American Medical Association.
In one study, researchers from Vancouver, Canada, divided 155 women ages 65 to 75 into three groups. Each followed different exercise regimens over the course of a year. In one group, 54 of the women did resistance training exercises once a week; in another, 52 women did twice weekly resistance training. Resistance training exercises emphasize strengthening the muscles and include the use of weights or lifting one’s own body weight, as in doing push-ups or pull-ups. The remaining 49 women served as controls, participating in twice-a-week classes that focused on balance and muscle tone training rather than resistance.
After a year, women in both of the resistance training groups scored higher on mental acuity tests that measured mental focus and attention than those in the balance and muscle tone group. They also scored higher on conflict resolution tests, and they were stronger.
“This has important clinical implications because cognitive impairment is a major health problem that currently lacks a clearly effective pharmaceutical therapy,” the authors wrote. In addition, they noted, “resistance training is not widely adopted by seniors.” The amount of exercise that the researchers assigned was moderate and within the range of exercise programs commonly recommended for seniors.
In the second study, researchers in Germany found that regular exercise was associated with reduced memory and thinking problems in older adults. Men and women, ages 55 and up, who engaged in moderate or high physical activity over a two-year period scored higher on cognitive exams than their sedentary peers.
The researchers assessed the exercise habits of, and performed memory tests on, nearly 4,000 older men and women in southern Bavaria, beginning in 2001. At the start of the study, 418 participants, or 10.7, percent showed signs of memory and thinking problems. After two years, 207, or 5.9 percent, of the initially healthy study participants developed memory problems.
Among those who rarely exercise, the incidence of new cognitive problems was 13.9 percent. In contrast, the incidence was considerably lower among those who exercise moderately (6.7 percent) or at high intensity (5.1 percent).
The study didn’t distinguish between specific types of exercise, like aerobic activities versus balance or strength training. Nor did it look at particular hobbies like walking or ballroom dancing, which earlier studies have shown may help keep the brain sharp. But the results add further weight to the idea that regular exercise can help keep the mind alert and lower the risk of cognitive problems, and maybe even Alzheimer’s disease, in old age.
A study last year, for example, from Rush University Medical Center in Chicago found that older adults who maintain their muscle strength are at lower risk of memory problems and Alzheimer’s disease than their same-aged peers. Those who were stronger were also less likely to have mild cognitive impairment, a form of memory loss that, while not as severe as Alzheimer’s, sometimes precedes the disease.
It may be especially important to exercise and adopt other healthy lifestyle measures early in life, given mounting evidence that Alzheimer’s risk can be cut by exercise during midlife. Alzheimer’s is a complex disease that likely depends on many factors, including the genes you inherit. Lifestyle factors are likely just one part of the preventive puzzle. While a twice-a-week visit to the gym won’t guarantee a physically and mentally robust old age, it may help you to look, feel, and act younger.
Teresa Liu-Ambrose; Lindsay S. Nagamatsu; Peter Graf; B. Lynn Beattie; Maureen C. Ashe; Todd C. Handy: “Resistance Training and Executive Functions: A 12-Month Randomized Controlled Trial.” Archives of Internal Medicine, Jan. 25, 2010, Vol. 170(2): pages 170-178.
Thorleif Etgen; Dirk Sander; Ulrich Huntgeburth; Holger Poppert; Hans Förstl; Horst Bickel: “Physical Activity and Incident Cognitive Impairment in Elderly Persons: The INVADE Study.” Archives of Internal Medicine, Jan. 25, 2010; Vol. 170(2): pages 186-193.