November 2, 1999
WASHINGTON (AP) â€” Negative stereotypes about getting old can hurt how people function, says a study that found healthy elderly people could suddenly walk faster when they were subconsciously fed positive images of aging.
How well older people walk â€” both their speed and whether they shuffle unsteadily â€” can predict their future health and independence. Falls are a huge health problem, and doctors recommend exercise programs for even the very elderly to strengthen muscles important for walking and balance.
But the new study, published today in the Journal of the American Geriatrics Society, suggests the mind also may play a powerful role â€” and that bleak expectations of aging may hurt even healthy people's strides.
"The effects are pretty profound," said lead researcher Jeffrey Hausdorff, a gerontologist at Boston's Beth Israel Deaconess Medical Center who invented thin, electronic shoe soles that precisely measure gait.
"It means we need to think about trying to reduce the stereotypes of aging," he added. "We concentrate a lot on physical function and things related to that. This shows other aspects of aging are also important."
Doctors have long explored the mind's role in medicine. Case in point: The "placebo effect" where some ill patients get better if they think the sugar pills they swallow are really drugs. Also, psychological studies suggest subconscious messages can influence perceptions.
That's where stereotypes enter. Harvard University graduate student Becca Levy conducted experiments that found negative stereotypes of aging worsened people's memory and self-confidence, while positive stereotypes improved them. But, she wondered, would those stereotypes also affect physical function?
Walking is a good test. Walking speed declines with age, and the elderly often shuffle because of poor balance. So Levy and Hausdorff tested 47 men and women, ages 63 to 82, who walked without a cane or walker.
First, participants walked a hallway almost the length of a football field. Using Hausdorff's special invention, the walkers' speed and "swing time," the time a foot spends off the ground, were recorded.
Then participants played a brief computer game. Positive words â€” such as "wise," "astute" or "accomplished" â€” flashed on half the screens just long enough to register subconsciously. Negative words â€” such as "senile," "dependent" and "diseased" â€” flashed to the other half.
Then they walked that long hallway again. This time, the positively influenced people walked 9 percent faster â€” improvement similar to some exercises. "Swing time" also increased, meaning they shuffled a little less.
Maybe positive stereotypes "change their mood or self-confidence and that impacts their behavior," theorized Levy, now an assistant professor at Yale University.
Walking didn't change for the negatively influenced people, who presumably already were exposed to society's negative stereotypes, she said.
Nobody knows how long the positive effects last, or if positive thinking also could help patients with arthritis, Parkinson's or other gait-altering diseases, said Hausdorff, who is continuing the research.
The finding "is an interesting one, and it makes sense in the context of ... the multiple factors that play a role in balance problems," said geriatric specialist Chhanda Dutta of the National Institutes of Health.
Why do the elderly have problems walking? Hausdorff explains with a demonstration: Strap 10-pound weights to each ankle, simulating how heavy a muscle-wasted leg is to lift, and don a pair of taped-over glasses to simulate bad eyesight. A youthful stride immediately turns to a tentative shuffle; the feet even turn in a way that skews balance.
There are good ways to avoid falls, Dutta said: Muscle-strengthening exercises that even 90-year-olds can do, adjusting medications that skew balance, proper eye care and clearing clutter from walking paths.
But one study that found tai chi improves the elderly's balance also concluded the exercise provides "a better self-awareness, self-perception of their body." Dutta said that finding fits with the new study's emphasis on positive thinking.