Young adults who devote more time to physical activity have a reduced risk of developing high blood pressure in the next 15 years, according to new research .
"This is reassuring and confirming evidence that physical activity is actually causally related to hypertension," said lead author David Jacobs, Jr., Ph.D.
Jacobs, an epidemiologist at the University of Minnesota in Minneapolis, and colleagues used data from a nationwide study that tracked the physical activity levels and blood pressure measurements of nearly 4,000 black and white men and women over a 15-year period.
Although previous studies have linked lack of exercise to hypertension development in middle-aged and older adults, this is the first to examine the relationship in young adults ages 18 to 30.
Overall, 634 adults developed hypertension, defined as having systolic pressure the top number of at least 140 mm Hg or diastolic pressure of at least 90 mm Hg or needing to take antihypertensive medications.
But "when we looked at average activity over a long period of time and the change in physical activity, both of those were inversely associated with hypertension, even with adjustment for other factors," such as age and family history of hypertension, Jacobs said.
Young adults who exercised an average of five times a week and expended 300 calories per exercise session experienced a 17 percent reduction in the risk of developing hypertension, compared to less active participants.
In addition, participants who increased their total physical activity from the start of the study actually decreased their risk of high blood pressure by 11 percent for every 1,500 calories they burned through exercise weekly.
The study offers "one more reason to follow existing recommendations to increase physical activity not only for healthy weight and overall cardio health, but to prevent the incidence of high blood pressure as we go from young adulthood to middle age," said Michael Zemel, Ph.D., a professor of nutrition and medicine at the University of Tennessee in Knoxville.
"To achieve levels of physical activity that are protective you don't have to go from being a couch potato to a gym rat," Zemel said.
Incremental changes in physical activity, if sustained over a long period of time, provide an enormous benefit, he said.