Exercise Alone No High Blood Pressure Cure
Exercise Lowers Blood Pressure -- but Older People Need More
April 12, 2005 -- A vigorous-intensity exercise program has many benefits for older people. But curing high blood pressure doesn't seem to be one of them.
The finding comes from a research team including Kerry J. Stewart, EdD, director of the research exercise physiology program at Johns Hopkins University in Baltimore. Stewart and colleagues know that some younger people can lower high blood pressure with exercise. So they set out to see whether a program of aerobic exercise and weight training could single-handedly cure mild blood pressure in older people.
More than 100 men and women took part in the study. All of these 55- to 75-year-olds had high blood pressure. With their doctors' consent, those on blood pressure drugs agreed to stop taking them during the study. Half the volunteers got the standard advice to exercise and follow a heart-healthy diet. The other half also got this advice -- but they also were enrolled in an exercise program.
The six-month exercise program consisted of three sessions per week. During each session, the volunteers stretched to warm up, then went through two sets of 10 to 15 repetitions of seven different exercises on weight machines. After that, they worked out for 45 minutes on a treadmill, a stationary bike, or a stair-stepper machine.
People Who Exercise Fared Better
At the end of the study, those in the exercise program were in much better shape. They didn't tend to lose much weight, because while they lost fat they gained muscle. They lost significant abdominal fat (a distribution of fat associated with heart disease risk) and increased their overall lean body mass.
And part of their blood pressure -- their diastolic blood pressure, or the "bottom" number -- was significantly lower than that of volunteers who did not exercise so aggressively. Diastolic blood pressure is a measure of the pressure within blood vessels between heartbeats or while the heart is resting.
Their systolic blood pressure also got lower. This is the "top number," or the pressure of blood flow when the heart pumps and is generally considered most important in elderly people. But it wasn't any lower than that of the volunteers not enrolled in the exercise program.
A close look at the data showed that volunteers who lost the most abdominal fat got the most improved blood pressure.
"Older people should still be encouraged to exercise because it produces numerous health benefits, but their expectations need to be modified about how much good the exercise alone will do for reducing systolic blood pressure," Stewart says, in a news release.
Older people have stiffer arteries than young people do. That may be one reason why six months of exercise does not produce as great a blood-pressure lowering effect in older people as in younger people. On the other hand, Stewart suggests, more vigorous exercise -- or exercise over a longer period of time -- may make blood vessels more flexible (a sign of healthy vessels) and offer greater blood pressure benefits.
It may also be true, Stewart says, that some older people may need to start blood pressure medications instead of relying solely on exercise.
The findings appear in the April edition of Archives of Internal Medicine.