Aerobic Exercise Reduces Blood Pressure
Study shows positive outcome across the board
MONDAY, April 1, 2002 (HealthDayNews) --Exercise is good for your blood pressure -- no matter your age, weight, race or gender. And it really doesn't matter whether you get exercise from a brisk walk, a fast run or few laps in the pool; the results are equally as good.
That's the conclusion of a new study published today in the Annals of Internal Medicine. Researchers conclude that almost any type of aerobic exercise is an effective tool for lowering blood pressure -- and that it works for just about everyone.
"Our report is the most comprehensive study in this area... [it] was able to provide an overall effect of exercise on blood pressure reduction across the board," says study author Dr. Jiang He, associate professor of epidemiology and medicine at Tulane University School of Public Health and Tropical Medicine.
Rather than conduct new clinical trials, He and his group analyzed evidence from many previous trials showing links between aerobic exercise and blood pressure. While many of these studies concentrated on specific groups -- such as white men or overweight blacks -- by combining all the results and analyzing them in a new way, He was able to show a multi-varied effect of exercise on blood pressure in all groups.
"Our study showed blood pressure reduction in overweight and non-overweight persons, and in blacks, whites, and Asians," says He.
He also found that all types of aerobic exercise work equally well. These include walking, running, jogging and swimming. Aerobic exercise also works for both those taking medication for high blood pressure and those with normal pressure.
While experts don't debate He's findings, some say it's important to note that the effects of exercise were modest at best, with an average per person drop in blood pressure of just 3-to-4 mm Hg. This means that if a person had a slightly elevated blood pressure count of 130 (higher number) over 86 (lower number), the aerobic exercise regimen could lower it to about 125 over 81. The numbers most often cited as normal blood pressure are 120 over 80.
"This can be important for people with borderline hypertension, and when combined with other lifestyle modifications such as a change in diet and quitting smoking, can drop pressure enough to keep some people from having to use medication to control blood pressure," says hypertension expert Dr. Samuel J. Mann, an associate professor of medicine at New York Weill Cornell Medical Center.
But Mann cautions those with extremely high blood pressure not to rely on exercise alone in controlling hypertension.
"Exercise is good for the heart, it's good for the body, it's good for your health and everyone should exercise regularly. Just don't stop taking your blood pressure medication unless your doctor says it's OK to do so," he says.
The new study involved 2,419 adults included in 54 different trials on exercise and blood pressure. All were physically inactive adults who agreed to exercise for a minimum of two weeks. They included Caucasian, Black and Asian men and women, aged 21-to-79 years, normal and overweight adults, and those with both normal and high blood pressure.
All studies utilized "aerobic" exercise -- activities that increase heart rate and improve the body's ability to use oxygen. Most of the studies involved participating in one or more aerobic activity for 20-to-30 minutes per session, several times a week.
By combining the results of all 54 studies in a process known as "meta analysis," He and his group got an overall view of the effects of exercise on many different groups of people.
The conclusion: On average, exercise helped study participants reduce systolic (top number) pressure by nearly 4 mm Hg, and diastolic (bottom number) pressure by slightly more than 2.5 mm Hg.
According to He, "The blood pressure reduction was slightly greater in persons with high blood pressure" (systolic 4.9 mm Hg and diastolic 3.7 mm Hg) than in persons with normal blood pressure (systolic 4.0 mm Hg and diastolic 2.3 mm Hg). However, he adds that these differences were not statistically significant.
What was significant, however, was that the reduction was accomplished whether people lost weight while exercising, something that was not readily apparent in previous studies.
The one surprising finding: Those in exercise programs lasting longer than six months saw a lesser reduction in blood pressure than those in the shorter studies -- a fact that Mann believes has more to do with compliance than anything else.
"When you ask people who don't normally exercise to start exercising, they do so with more frequency at the start of the program, with levels of activity dropping off the longer the program goes on," says Mann, who adds that the key to retaining the pressure-lowering effects of exercise is to simply keep doing it.
And He agrees, adding, "Adults should consider lowering blood pressure [as] one of the many reasons to exercise 30 minutes several times per week," he says.
What To Do
For more information on the effects of exercise on blood pressure, visit Life Fitness Education.
To learn more about how high blood pressure affects your health, check The Blood Pressure Center.
To learn how diet and other lifestyle modifications can lower your blood pressure, visit The American Heart Association.