MONDAY, Sept. 2, 2002 (HealthDayNews) -- A woman's fitness level may help predict her future risk of hypertension, says a study in the September issue of Psychophysiology.
"We think these initial findings are sufficiently positive to encourage a randomized controlled trial that will provide a better test of the independent effects of cardiorespiratory fitness on responses during stress," says study author Rod K. Dishman.
The study included 13 men and 13 women, average age mid-20s, with normal blood pressure. They all exercised moderately or vigorously at least three times a week over the previous year.
They were given three tests. They did mental math by subtracting a two-digit number from a four-digit number without the aid of a calculator or paper and pencil. In another test, they place an ice bag on their forehead for two minutes. In the third test, they immersed their right hand in ice water for two minutes.
During all these tests, the researchers measured the subjects' blood pressure, heart rate, breathing frequency and calf muscle blood flow.
The mental math test increased both systolic and diastolic blood pressures and blood flow to the calf muscle. The hand/ice water test increased blood pressure readings, but had no effect on calf muscle blood flow. The forehead/icebag test resulted in only slight blood pressure increases and no changes in calf muscle blood flow.
The researchers found something particularly interesting during the hand/ice water test. Women who were more fit had less of an increase in systolic blood pressure.
"The blunted systolic blood pressure response among the fitter women has implications for clarifying the usefulness of the [hand in ice test] as a predictor of future risk of hypertension among women," the researchers write.
More information
Learn how to keep your blood pressure under control from the National Heart, Lung, and Blood Institute.
