Lack of Exercise at Young Age Raises Hypertension Risk

High blood pressure, or hypertension, increases significantly with low levels of physical activity and fitness, a study of young adults shows.

The study in the journal Hypertension found that about one-third of all high blood pressure cases could be prevented with increased physical fitness.

"Those who were the least physically fit, as determined by the amount of time on a treadmill and self-report, were more likely to develop hypertension," says study author Mercedes Carnethon, Ph.D., at Northwestern University.

Because high blood pressure does not generally have warning signs or symptoms, it has been called "silent killer" because many people do not realize they have it.

High blood pressure can be detected in a quick, painless manner by having a blood pressure measurement performed by a physician or other healthcare professional. Blood pressure checks should be performed regularly, at least once a year or more often, if recommended by a healthcare provider.

Long-Term Study Uses Treadmill, Questionnaires

For the study, researchers asked if levels of physical activity and fitness as a young adult affect risk of developing high blood pressure later in life.

To answer that question, 4,618 men and women between 18 and 30 years old were recruited for a 20-year study of cardiovascular disease risk factors. Study volunteers completed a treadmill test and a physical activity questionnaire when the study began. In addition, their overall health was assessed at six follow-up appointments over 20 years.

Just over 1,000 people in the study developed high blood pressure, which was defined as having blood pressure that is higher than 140/80 millimeters of mercury (mm Hg) or having been prescribed medication to treat high blood pressure.

Even after adjusting for other known heart disease and high blood pressure risk factors - such as smoking, age, race, sex, cholesterol, and diet - the researchers found that lower levels of physical activity and fitness were associated with an increased risk of high blood pressure.

Dr. Carnethon says this study is especially helpful because it did not rely solely on self-report of physical activity, but relied on an objective measure of physical activity - the treadmill test.

If people moved more and were able to increase their fitness level, the researchers estimate that about 34 percent of hypertension cases could be prevented.

Old Habits Are Hard to Change

The reason sedentary behavior in young adults translated to a higher risk of elevated blood pressure later in life, says Dr. Carnethon, was probably because the sedentary behavior did not change as people grew older.

"The results of this study aren't too surprising, but what I think is impressive is the amount of hypertension that can be prevented, says Dr. Goutham Rao, at Children's Hospital of Pittsburgh.

"For example, in white women, the difference between low levels of fitness and high levels of fitness is a fivefold higher risk in the low level group," he says. "The magnitude of the difference was surprising."

"Hypertension is largely controllable or reversible,” explains Dr. Rao. "The good news is that there's no point at which you can not benefit from increased activity." But, he says, it is better to start younger because people who are active in their youth are more likely to stay active as adults.

One in three Americans has hypertension, according to the Centers for Disease Control and Prevention (CDC). High blood pressure is a risk factor for heart disease, stroke, and kidney disease.

Regular physical activity is one way that a person can help keep blood pressure at normal levels. The CDC recommends at least 30 minutes of moderate physical activity on most days of the week.

Always consult your physician for more information.