Jan. 11, 2024 – What you already know: Physical activity helps ease high blood pressure.
What you may not know: Researchers have found that one type of exercise – and one single exercise in particular – helps lower blood pressure especially well.
A 2023 review of 270 prior studies including nearly 16,000 people found that a program of isometric exercise reduced systolic blood pressure (the top number) by 8.24 mm Hg (or milligrams of mercury, a measure doctors use for blood pressure), and diastolic blood pressure by 2.5 mm Hg.
Isometric exercise brought bigger blood pressure benefits than aerobic exercise (a blood pressure drop of 4.49 points and 2.53 points), resistance training (down 4.55 and 3.04 points), and interval training (a decrease of 4.08 and 2.5 points).
“We, along with other research groups around the world, have clearly demonstrated the efficacy of isometric exercise to lower resting blood pressure in people with blood pressures ranging from normal through to hypertensive,” said study co-author Jim Wiles, PhD, director of clinical exercise science research at Canterbury Christ Church University in England.
You perform an isometric exercise when you flex your muscles to hold a position. (When you move, those are called isotonic muscle contractions.)
“A lot of people actually do isometric exercise and don’t realize it, for example, when you go to a yoga class,” said Neil Smart, PhD, a professor of exercise and sports science at the University of New England in Australia.
Imagine squeezing a tennis ball for 30 seconds. When you hold an isometric pose, your straining muscles constrict the surrounding blood vessels. Partially pinching off blood flow this way while flexing causes a buildup of anaerobic metabolites (substances that inhibit the flow of oxygen).
“Even though it’s only a localized activity, there seems to be a whole-body effect in terms of blood pressure,” Smart said.
Research has only looked at three exercises: Leg extensions (performed with weight on a leg extension machine), hand grip squeeze, and wall squats. It’s possible other isometric exercises may offer benefits – they just haven’t been studied specifically for blood pressure.
Wall squats in particular seem effective. When 24 middle-aged men with high-normal blood pressure performed isometric wall squats three times a week for a year, their systolic blood pressure decreased by 8.5 points, and their diastolic blood pressure decreased by 7.3 points, according to a 2022 study in the Journal of Hypertension.
“How the repetition of this acute response translates into chronic blood pressure changes is not well understood, but it is linked to potential changes in local vascular function, autonomic vascular function and possibly structural vascular adaptations,” said study author Jamie O’Driscoll, PhD, a researcher at Canterbury Christ Church University in England
If you have blood pressure issues, don’t pack up your running shoes or stop lifting weights.
“No one should replace aerobic exercise with isometric,” said Philip Millar, PhD, an associate professor of physiology at the University of Guelph in Canada. “For example, isometric training does not appear to change cholesterol levels, a known cardiometabolic benefit of aerobic exercise.”
Think of isometric exercises as something to add to your regular physical activity. And that’s easy, since you can do them a tiny space, without leaving the house, and you don’t need gym equipment or a lot of extra time.
That’s especially important for people who can't get around well, particularly older people or those with obesity who find walking for 30 minutes to be too difficult. And people who can’t afford a gym membership, travel often, or simply lead busy modern lives can always squeeze in some isometric exercises.
For more details and similar articles, go to www.WebMD.com.