'T'ai chi' Lowers Blood Pressure For Older Adults

"You better believe we were surprised by those results," says Deborah R. Young, Ph.D., assistant professor at the Johns Hopkins University School of Medicine in Baltimore. "We were expecting to see significant changes in the aerobic exercise group and minimal changes in the t'ai chi group."

T'ai chi, which has been studied by other scientists as a balance and flexibility exercise, consists of a series of 13 movements, each of which has 10 to 15 additional moves.

After 12 weeks, systolic blood pressure had fallen significantly, an average of 8.4 millimeters of mercury (mm Hg), in the aerobic exercise group. However, it also fell significantly, 7 mm Hg, in the t'ai chi group. The beneficial effects were seen in both groups after only six weeks of exercise, Young adds.

"It could be that in elderly, sedentary people, just getting up and doing some slow movement could be associated with beneficial reductions in high blood pressure," she says.

T'ai chi and similar light-intensity activities are within the capabilities of most older people.

Because her research is a pilot study, Young recommended that older citizens not hang up their walking shoes and take up t'ai chi. "Until we know more, I encourage people to go out and do brisk walking on a regular basis. We know it's associated with a multitude of health benefits," she says. With t'ai chi, these health benefits have not yet been established.

Young says previous studies have indicated that moderate aerobic exercise, such as brisk walking or bicycling at a moderate intensity level, could lower blood pressure. The pilot study evaluated whether light exercise would have any effect on blood pressure.

High blood pressure affects an estimated one in four adults in the United States and is a risk factor for stroke and heart attack.

The scientists studied 62 sedentary adults 60 years old and over who were recruited from the Baltimore community. Forty-five percent of the subjects were African-American and 79 percent were women. None of the participants took blood pressure medication. Their average systolic blood pressure (the upper number) was 130-159 mm Hg -- a range that encompasses high normal to stage 1 high blood pressure. Their diastolic pressure was in the normal range at less than 95 mm Hg.

Half the adults were randomly assigned to a 12-week program of moderate aerobic exercise consisting of brisk walking and low-impact aerobics. The other 31 individuals learned t'ai chi.

"We do not know why light exercise provided as significant a decrease as the moderate exercise," Young says. She stressed that her pilot study needs confirmation by research on larger groups, including a control group that remains sedentary.

The study was presented at the American Heart Association's 38th Annual Conference on Cardiovascular Disease Epidemiology and Prevention. Young's co-researchers are Lawrence J. Appel, M.D., M.P.H., and Sun-Ha Jee, Ph.D.