A simple five-minute daily breathing exercise lowers blood pressure and potentially improves heart health as well as — or even better than — exercise or medications, say researchers at the University of Colorado Boulder.
The technique — known as high-resistance inspiratory muscle strength training (IMST) — asks patients to inhale deeply through a hand-held device that provides resistance.
To get a sense of how the technique works, researchers suggest imagining “sucking hard through a tube that sucks back.”
As part of the UC Boulder study, 36 adults ages 50 to 79 with above-normal systolic blood pressure readings — 120 or higher — were broken into two groups: Half performed high-resistance IMST for six weeks, and half did a placebo protocol, which involved much less resistance.
(Systolic blood pressure refers to the first or top number in a blood pressure reading. For example, if your reading is 120/80, your systolic blood pressure is 120.)
After six weeks, the systolic blood pressure of the IMST group dipped nine points on average. That reduction surpasses what is normally achieved by walking 30 minutes a day, five days a week. It is also equal to the effects of some drugs that aim to lower blood pressure.
In addition, those in the IMST group recorded a 45% improvement in vascular endothelial function, which is the ability of arteries to expand upon stimulation. Levels of nitric oxide — a molecule that dilates arteries and prevents plaque buildup — also increased.
Finally, markers of inflammation and oxidative stress fell significantly. Higher levels of these markers are linked to increased heart attack risk.
These findings were published recently in the Journal of the American Heart Association.
IMST has been used for decades to help patients with respiratory disease to strengthen their diaphragm and other breathing muscles. Now, researchers suggest that more widespread use of IMST might help aging adults lower their risk of cardiovascular disease, the No. 1 cause of death in America.
In a press release, Daniel Craighead, lead author of the study and an assistant research professor in UC Boulder’s Department of Integrative Physiology, says:
“There are a lot of lifestyle strategies we know can help people maintain cardiovascular health as they age. But the reality is, they take a lot of time and effort and can be expensive and hard for some people to access. IMST can be done in five minutes in your own home while you watch TV.”
The researchers note that 65% of U.S. adults over age 50 have above-normal blood pressure, which raises their risk of heart attack or stroke.
Traditionally, it has been recommended that those performing IMST engage in a 30-minute-per-day regimen at low resistance. But Craighead and others have found that a reduced regimen of 30 inhalations per day at high resistance, six days per week also offers cardiovascular, cognitive and sports performance benefits.
The researchers noted that the IMST regimen may be especially beneficial for postmenopausal women. Earlier research has found that postmenopausal women who are not taking supplemental estrogen do not see as much benefit to vascular endothelial function from exercise as men do.
However, IMST appears to boost vascular endothelial function in women just as much as men. According to Craighead:
“If aerobic exercise won’t improve this key measure of cardiovascular health for postmenopausal women, they need another lifestyle intervention that will. This could be it.”
The particular breathing-muscle training device used in the study is called a POWERbreathe K3, which is made by a company based in England and has a retail price of a few hundred dollars. But the researchers note they are developing a smartphone app that will enable people to do the same IMST regimen at home with other devices as well. They also note that anyone considering IMST should talk to their doctor first.