Do you remember the last time that you let out a big granddaddy sigh? Felt pretty good, eh? Science says there’s a reason for all that goodness AND that you can invite it in, at will, any time.
The Huberman Lab is a podcast hosted by Stanford neuroscientist Dr. Andrew Huberman, Ph.D. The focus of the podcast is providing tools that help people to reduce stress in real time. In other words, the goal is to feel calm now amid the stress-inducing activity.
Many of the tools I have provided in the blog, such as meditation and breath work, are best practiced away from the moment of stress. Training the brain to perform differently, they build resilience and increase your capacity to effectively manage difficult situations in the future. These mindfulness methods are generally not intended as psychological first aid in the moment of crisis.
Huberman, and his lab crew, on the other hand, are interested in developing tools that help you lean into stress. Tools you apply when you’re trying to dodge a hard tackle on the playing field of life. One of the best tools they have discovered for this job is cyclic sighing.
Humans and other mammals sigh automatically every few moments to support proper lung function (Li et al, 2020). You don’t think about these sighs. This form of basal sighing is a natural part of the breathing process. These physiological sighs act as an automatic reset. They happen spontaneously in times such as deep sleep when a build-up of carbon dioxide gas (the waste product of respiration) occurs in the blood stream. High levels of carbon dioxide trigger the impulse to breathe. The physiological sigh is a unique breathing pattern that facilitates a large release of carbon dioxide.
The physiological sigh consists of a double inhale followed by an extended exhale. Recall seeing a child, an adult or, even you, crying uncontrollably. The double inhale, extended exhale pattern occurs spontaneously to help catch the breath and act as a self-soothing mechanism. The reason the physiological sigh is so impactful is that it offloads a pile of carbon dioxide.
The lungs are not just two balloons. On average, the lungs contain 480 million tiny air sacs called alveoli. The alveoli are at the heart of gas exchange in your body, picking up the incoming oxygen and releasing the outgoing carbon dioxide. Together, the alveoli compose an overall surface area equivalent to the size of a tennis court which gives them a huge capacity for gas exchange.
The build-up of carbon dioxide in the blood creates stress and that gets magnified by any of the alveoli that are in a collapsed state. The second inhale of the physiological sigh is particularly important in terms of the alveoli because it re-inflates those tiny little air sacs so, when you exhale, the volume of carbon dioxide discarded is maximized.
The practice of cyclic sighing takes advantage of the natural physiological sigh for decreasing stress. Cyclic sighing is just the voluntary execution of the physiological sigh. Science has validated that if you’re feeling stressed in any circumstance, inhaling twice through the nose, followed by a long exhale through the mouth (about twice as long as the first inhale) repeated once, twice, or three times will dramatically lower your level of stress quickly and allow you to feel calmer. Repeated as a short breathwork practice for 5 minutes, cyclic sighing has been shown in clinical trials to improve sleep, lower resting heart rate, and enhance mood.
So, the next time the cold, boney hand of stress grabs a hold, inhale deeply, inhale a little more and let it out with a big, long, slow sigh 1-3 times.