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High-Resistance Inspiratory Muscle Strength Training (IMST) is the practice of inhaling vigorously through a hand-held device that provides resistance. The study compares it to sucking hard through a tube that sucks back.
Daniel Craighead, an assistant research professor in the Department of Integrative Physiology at the University of Colorado at Boulder, says that 30 inhalations per day at high resistance (s0, see it as one breathing workout) may improve cardiovascular health, cognitive health and sports performance.
“There are a lot of lifestyle strategies that 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,” Craighead says. “IMST can be done in five minutes in your own home while you watch TV.”
Craighead and a team of researchers at the University of Colorado at Boulder recruited 36 healthy adults ages 50-79 and had half of them did IMST for six weeks. The other half did a breathing workout regimen with much lower resistance. The first group saw a 45 percent improvement in vascular health and an increase in levels of nitric oxide, a molecule which is important in preventing plaque buildup in the arteries. Their inflammation and oxidative stress levels were significantly lower, as well.
Remarkably, participants who performed IMST saw a nine-point drop in systolic blood pressure (the top number) on average. That means IMST was more effective than walking 30 minutes a day, five days a week, at least in this study group. It’s also as effective as some pressure-lowering medications.
“If you’re running a marathon, your respiratory muscles get tired and begin to steal blood from your skeletal muscles,” said Craighead, who uses IMST in his own marathon training. “The idea is that if you build up endurance of those respiratory muscles, that won’t happen and your legs won’t get as fatigued.”
A research group is in the process of creating an app to show people how to easily practice IMST at home.
“It’s easy to do, it doesn’t take long, and we think it has a lot of potential to help a lot of people,” said Craighead.
As always, talk to your physician before substituting any medicine or drugs with IMST.
How To Use IMST
- Pick your resistance from 1-5.
- Place nose clips on your nose to ensure that you’re only doing breathing from your mouth.
- Sit up straight and put the mouthpiece into your mouth. Breathe in for as deep and hard as you can for two seconds, then breathe out. Repeat for 15 breaths per minute.
- Do this for 10-15 minutes a day, four or five times a week.
You can also find video tutorials for IMST.