The study, published recently in the Journal of the American Heart Association, provides strong evidence that the ultra-time-efficient manoeuvre known as High-Resistance Inspiratory Muscle Strength Training (IMST) could play a key role in helping ageing adults fend off cardiovascular disease.
“There are a lot of lifestyle strategies that we know can help people maintain cardiovascular health as they age. But they take a lot of time and effort and can be expensive and hard for some people to access,” said lead author Daniel Craighead, an assistant research professor in the Department of Integrative Physiology. “IMST can be done in five minutes in your own home while you watch TV.”
Developed in the 1980s as a way to help critically ill respiratory disease patients strengthen their diaphragm and other inspiratory (breathing) muscles, IMST involves inhaling vigorously through a hand-held device that provides resistance.
Initially, when prescribing it for breathing disorders, doctors recommended a 30-minute-per-day regimen at low resistance. But Craighead and colleagues have been testing whether a more time-efficient protocol of 30 inhalations per day at high resistance, six days per week could also reap cardiovascular, cognitive and sports performance improvements.
After six weeks, the IMST group saw their systolic blood pressure (the top number) dip nine points on average, a reduction which generally exceeds that achieved by walking 30 minutes a day five days a week.
That decline is also equal to the effects of some blood pressure-lowering drug regimens. Markers of inflammation and oxidative stress, which can also boost heart attack risk, were significantly lower after people did IMST.
“We have identified a novel form of therapy that lowers blood pressure without giving people pharmacological compounds and with much higher adherence than aerobic exercise,” said senior author Professor Doug Seals.
