Nearly two-thirds of adults living in the United States have high blood pressure, defined as having a systolic pressure of 130 mm Hg or higher or a diastolic pressure of 80 mm Hg or higher. Aerobic exercise is one of the most effective strategies for maintaining healthy blood pressure, but fewer than 40 percent of adults meet current exercise guidelines. Findings from a new study suggest that high-resistance inspiratory muscle strength training improves blood pressure.

High-resistance inspiratory muscle strength training is a form of resistance exercise that strengthens the muscles involved in breathing. The technique involves inhaling forcefully via the mouth through a portable, hand-held device that provides resistance against the inhalation. The frequency of training, number of repetitions, and amount of resistance vary based on the participant’s needs and respiratory health.

The study involved 36 healthy adults (ages 50 to 79 years) who had high systolic blood pressure. Half of the participants performed high-resistance inspiratory muscle strength training (five sets of six breaths, with one minute of rest between sets) for six weeks. The other half performed sham breathing exercises against very little resistance. The study investigators measured various biomarkers associated with stress and cardiovascular health in the participants' blood. They measured the participants' resting blood pressure at four time points (screening, baseline, end‐intervention, and follow‐up) and measured ambulatory pressure via a portable monitoring device every 20 minutes during the day and every 60 minutes at night over a 24-hour period. They also measured flow‐mediated dilation, an indicator of vascular endothelial function. They treated endothelial cells with plasma drawn from the participants before and after the intervention to assess the bioavailability of nitric oxide, a key signaling molecule in the cardiovascular system.

When participants performed with high-resistance inspiratory muscle strength training, their resting systolic blood pressure decreased from an average of 135 mm Hg to an average of 126 mm Hg. Similarly, their diastolic blood pressure decreased from an average of 79 mm Hg to an average of 77 mm Hg. Their 24-hour systolic blood pressure decreased, and their arterial flow‐mediated dilation improved by approximately 45 percent. The sham training had no effects on blood pressure or flow-mediated dilation. Participants who performed high-resistance inspiratory muscle strength training exhibited decreases in C‐reactive protein (a biomarker of inflammation) and improvements in other markers associated with cardiovascular function. Nitric oxide bioavailability increased in both groups but was 10 percent higher among those who performed high-resistance inspiratory muscle strength training.

These findings suggest that high-resistance inspiratory muscle strength training demonstrates promise as a lifestyle strategy to lower blood pressure. Another lifestyle behavior that reduces blood pressure is sauna use. Learn more about sauna use in our overview article.

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