File this one in the “strange but perhaps true” folder: How you exercise your upper arms could help lower your blood pressure reading at your next doctor’s appointment. And before you make any guesses about the exercise, be assured that it isn’t the traditional bicep curl. On the contrary, it’s something less vigorous — but surprisingly effective for the cardiovascular system: isometric resistance training. Not sure what isometric resistance training is? As an article from the Mayo Clinic explains, it’s the act of engaging your muscles statically. (In other words, no movement of the muscles is involved beyond getting them into a specific position.)
It might sound too good to assume that adding a new bicep exercise into your workout regimen could be a boon for your blood pressure. Yet, according to multiple studies, isometric resistance training exercises like bicep curls show tremendous potential for lowering blood pressure.
Isometric bicep curls might lower high blood pressure
A 2021 systematic review and meta-analysis published in Hypertension Research documented the potential of isometric resistance training for being an assistive tool for individuals who want to lower their blood pressure. As noted by the authors, “IRT [isometric resistance training] appears safe and may cause clinically relevant reductions in BP [blood pressure].” Further, a 2023 meta-analysis from Current Hypertension Reports came to the same conclusion, with researchers stating that isometric resistance training could help lower both systolic and diastolic blood pressure levels in adults diagnosed with hypertension. Another meta-analysis, this time from a 2019 issue of the Journal of Hypertension, was equally as positive.
Perhaps the most exciting scientific research into the possible blood pressure-lowering effects of isometric resistance training came from a 2022 meta-analysis found in the British Journal of Sports Medicine. There, the most effective hypertension-fighting exercises were listed in order of their effectiveness. Isometric exercise training took the top place, beating out aerobic exercises and high-intensity interval training (HIIT) modalities.
How isometric bicep curls might lower blood pressure
But why exactly do isometric resistance exercises like bicep curls work so well for your cardiovascular system? Dr. Neil Smart, a professor from the University of New England in Australia, gives a background on the science behind the phenomenon in a WebMD article. As Smart says, “The body doesn’t like [isometric resistance exercises] . . . As soon as you stop squeezing, blood flow will be normalized and then enhanced in an attempt to clear up this mess that’s been created in the forearm.”
The article goes on to further illustrate the process, explaining that the body releases a high dose of nitric oxide into the bloodstream. According to a 2022 article on nitric oxide supplementation from the Journal of Preventive Medicine and Hygiene, nitric oxide both improves cardio health and reduces blood pressure.
How to engage your muscles with isometric bicep curls
You can easily do isometric resistance training as part of your weekly arm workout. You just have to understand how isometric resistance training works in action to take advantage of the would-be health benefits of the exercise. One method to understand how it works is to compare it with common movement-based exercises. Consider the elements of a conventional bicep curl, for example. During the exercise, you would force your bicep muscles to change positions and lengths by contracting and extending the muscles in your arm repeatedly. Typically, these contract-release motions are called “reps” because they repeat the same motion several times in a row. This type of exercise falls under the category of traditional resistance training (without the isometric aspect).
As explained in a 2021 study published in Sports, resistance training is a technique to improve muscle strength and endurance. However, isometric resistance training isn’t meant to bulk up the muscles by making them work against a counterweight; it’s meant to force them to work against themselves. During an isometric resistance training curl, you would lift a weight enough to engage your biceps. Then, instead of allowing your arm to bring the weight down right away, you would hold the weight steady for several seconds. In this contracted state, your muscles would work as stabilizers. Not only would you still get that “burn,” but you’d potentially help decrease your blood pressure levels as well.
You aren’t relegated to just focusing your isometric resistance training on your biceps, either. All types of isometric resistance training are fair game if you want to switch up your workout and address your hypertension at the same time. For example, you may want to take up isometric handgrip exercises. According to a 2022 study from Systematic Reviews, adults who regularly engaged in isometric handgrip training experienced blood pressure level benefits. Also, certain exercise philosophies and workouts base many movements on isometric resistance training, including yoga. As outlined by Healthline, yoga offers plenty of isometric resistance training poses for you to explore.