The emWave2 is a $199 handheld device sold by HeartMath, LLC, a wholly-owned subsidiary of Quantum Intech, Inc., which owns the patents on the emWave inventions from the research and development done at their non-profit Institute of HeartMath (IHM).
On the surface, the emWave2 seems to do nothing more than simply measure your pulse then blink a light and beep. That seems like a high price for something so small and simple.
And yet, it changed my life like no other device ever has. It gets my enthusiastic recommendation. Read the rest of my emWave2 review to learn why.
What’s going on behind the scenes is a precise calculation the emWave2 performs by measuring the time between heartbeats and calculating the variations in those interval lengths. This important biological marker of health is your heart rate variability (HRV).
There's an excellent paper titled A Healthy Heart is Not a Metronome if you want to read a review of current science on this topic. Here’s the condensed version: if your heart is beating “on the beat” like a metronome, that’s a bad sign. The tempo of the beat of a healthy heart varies—sometimes a lot. We want to have a high HRV.
The research keeps growing every year. HRV correlates with almost every health outcome worth studying. It is lower in depressed patients and higher in those who thrive best after a heart attack. Low HRV in people with diabetes predicts a higher likelihood of dying from any cause five whole years later. Extensive essays could be written just listing correlations like these.
Trends in HRV also correlate with successful athletic training. As a rule, reduced HRV implies overtraining, and higher HRV is evidence of a better training response (1).
The correlation with heart disease alone is enough to show we should all care about HRV. Heart disease is the number one cause of death worldwide.
In college, I experienced my first panic attack. Nothing stressful was happening when it hit. A sense of dread washed over me out of nowhere. It was obvious that something was wrong. I had no idea what it was or how to fix it. I felt out of control of my own body, which made it worse.
I ended up rushing to the medical center on campus. They referred me to a campus psychologist. They said I should try some breathing exercises whenever I felt a panic attack coming on.
However, no amount of closing my eyes and counting my breaths ever lessened the attacks. I actually felt a little insulted. I may get a lot of things wrong. But surely, I do a good enough job breathing, right?
I imagine this is what people who are told to try an emWave2 for their anxiety might feel at first.
Ten years later, I understand now that we are breathing wrong, which is the root cause of most, if not all, anxiety and panic attacks. But it doesn't work quite the way my psychiatrist thought.
A panic attack is one of the most extreme side-effects of poor breathing habits. By way of analogy, obesity is one of the most extreme side-effects of eating excessive junk food.
Well, they only ever gave me breathing exercises to try during a panic attack. That's like telling someone to jog around for a few minutes when they notice they're obese.
It's too little too late. The damage has already been done by then.
The real cause of most anxiety is poor breathing habits from the time you wake up to the time you fall asleep. It doesn't even stop there. How you breathe while you're sleeping matters, too.
When I discovered the emWave2, I wasn't trying to cure my panic attacks. I didn't realize that breathing was so important either. The HeartMath Institute itself doesn't emphasize this. The technique they promote for raising HRV involves focusing on positive feelings.
It took a month of experimenting with the emWave2 before I saw real results. Initially, I believed the emotional tone of my thoughts was the catalyst for improvement as the instructions had conveyed. Soon, I discovered that wasn't the answer. There was no correlation at all between what I thought about and my results.
When I finally noticed that my breathing had an impact, I started paying closer attention. Then I narrowed it down to a small window of breathing paces that did the job: five to six breaths per minute.
In the beginning, the device stayed silent and red 90% of the time. By the end of the month, I was able to make the light turn green and give me the satisfying ding of success almost by command.
I could also feel a difference when it turned green even though I didn't fully understand why it worked. In those moments, I noticed that I was breathing much slower than usual.
It was only later that I would realize how important this discovery was that I had made. An immense body of research shows countless benefits for everyone from breathing within this window.
It's been a few years since I took that month out to practice breathing with the emWave2 every day. I haven't experienced a single panic attack since then, even though I've been through plenty of stress.
For example, I'm prone to claustrophobia. A subway in New York malfunctioned and stranded me in a tight underwater tunnel for hours. People started panicking. A few even talked about throwing the driver out and trying to fix it themselves. Instead of feeling wracked with anxiety, I was the one using the device to help a few other people stay relaxed.
It felt incredible to not only stay calm under pressure but to be the one helping others remain calm as well. I owe my transformation entirely to using the emWave2 because the device helped me improve my HRV.
What exactly is anxiety? Almost everyone knows how it feels. But what is it? What system in the human body is malfunctioning when it happens?
Most people have heard the term “fight or flight.” If you start walking across the street and see a bus speeding towards you, your body will freeze for a second, and then you will run for your life! So far, so good. It is a life-saving reaction in those moments.
But the fight or flight response isn't always all-or-nothing. We don't enter it only in special extreme conditions. We're commonly using our fight or flight response to various degrees throughout the day.
The fight or flight response comes from one of the two sides of our nervous system. That's the sympathetic nervous system, which I'll refer to as the SNS from here on.
The SNS is involved in both the “flight” state of high anxiety and also the “fight” state, that urgent need to react immediately! Road rage, for instance, is an indication of the SNS being overactive.
The other side of the nervous system produces what's called the “rest and digest” response. That's the parasympathetic nervous system, which I'll refer to as the PNS.
The balance between the SNS and PNS is like a see-saw.
Every SNS increase reduces the PNS, and vice versa. So in a panic attack, one might be all the way over in full-blown activation of the SNS.
Alternatively, someone could also spend most of their day shifted three-quarters of the way towards max SNS activation. They would probably experience more anger in traffic and also have greater difficulty trying to fall asleep at night.
So, what determines how your body balances the SNS and PNS? Your breathing rate is the key.
The key to wellness is how you habitually breathe all day every day. This eye-opening study found that it can take three full months of better breathing habits before the SNS finally calms down.
Not only that, but there's also another way poor breathing habits increase anxiety and other health problems.
Did you know that people who have anxiety are more likely to develop heart disease and have heart attacks? There's a reason panic attacks and heart attacks feel so similar. It's because poor breathing habits mean your brain and your heart both get less oxygen.
Ask yourself, how would you change your breathing, right at this moment, if you wanted to get more oxygen to your brain?
Think about it and then start breathing that way for a minute. Go ahead and try it out right now to see if it works.
. . .
. . .
. . .
Did you breathe faster than before? Will breathing quickly help you take in more oxygen for your brain?
Since oxygen is in the air, it would seem intuitive that taking in more air would get more oxygen into your brain. But in practice, that's the exact opposite of what works.
Surprisingly, the correct strategy is actually: breathe slower.
Here's why. Unless you're exercising, your bloodstream already has more oxygen than your body can use. Not all that oxygen can make it into your organs and tissues. Believe it or not, the amount of oxygen in your blood is usually irrelevant (if you're healthy). (1)
The Bohr effect explains how oxygen makes its way from your bloodstream into your brain, heart, and all the other places it needs to go.
Bohr's brilliant discovery was that carbon dioxide is what delivers the oxygen where it needs to go.
So think of oxygen as the food that lines your grocery store shelf.
Carbon dioxide (CO2) is like the workers unloading the farm-to-market delivery trucks. If they stop working, it doesn't matter how many farms and factories are producing food. People are going to go hungry.
Breathing faster won’t increase your blood oxygen under normal circumstances. But it will cause you to breathe out more CO2, thereby reducing the levels in your body needed for oxygen delivery. You can see how breathing faster hinders CO2 from helping deliver oxygen to the tissues and organs that need it.
Rapid breathing doesn't increase the oxygen going to your brain, heart or other organs. Bound oxygen is like food in the back of a delivery truck instead of available at the grocery store. More food produced by the farms doesn’t help address the empty shelves at the grocery store if no one is available to unload the trucks.
So when you breathe faster and reduce CO2, your brain and heart are deprived of oxygen.
That's why anxiety correlates with heart disease. Rapid breathing results in insufficient CO2. Low levels of CO2 will constrict blood vessels and keep the oxygen bound, making it less available to your brain and heart. The oxygen deprivation triggers worsening anxiety.
A common folk remedy for panic attacks is to breathe into a paper bag. It helps because if you hyperventilate that way, at least you'll breathe back in some of the CO2 you're blowing out.
If your heart and brain run low on oxygen during over-breathing, other organs do too. So chronic over-breathing may contribute to a wide range of poor health outcomes.
Let's take a random condition that you wouldn't expect to have any correlation: diabetes. If either the pancreas or adipose tissue (i.e. fat) are deprived of oxygen, that deprivation may contribute to the development of diabetes. Studies have proven that HIF-1 (which is a marker of low oxygen) creates dysfunctional insulin resistance.
Other studies have looked at the breathing rate of diabetic patients. Those with diabetes average 13-17 liters per minute. What’s the average for healthy subjects? Their rate is only 5-8 liters per minute. Surprisingly, even though those with diabetes breathe two to four times as much air, they often have markers of low oxygen levels in their tissues and organs.
We find similar results in nearly every category of health problems. With hardly any exceptions, unhealthy people over-breathe considerably more than healthy subjects.
Of course, this isn't conclusive evidence of cause and effect. We can't be 100% sure that over-breathing isn't somehow an adaptive response to illness. But we do know that over-breathing reduces oxygen delivery to vital organs and tissues. So this makes a case that deserves taking a good look at our breathing habits.
After I discovered five to six breaths per minute kept me in the green on the emWave2, I made my way through lots of scientific research.
The easy way to remember this pace is to know that 5.5 breaths per minute will be a 5.5 second inhale with a 5.5 second exhale. If you breathe at this pace, you don't necessarily need the emWave to get the health benefits.
Higher HRV plays a significant role in reducing all-cause mortality. It may improve health because slower breathing increases oxygen delivery throughout the whole body. Additionally, increasing HRV enhances the “rest and digest” state of PNS activation to aid in the absorption of nutrition from our food and promote deep, restorative, healing sleep.
As a side note, there is a device called the RESPeRATE. It costs more than the emWave2. Unlike the emWave2, it doesn't measure HRV. It just beeps to let the user know the pace to breathe while gradually slowing down the breathing rate. The FDA approved the RESPeRate device as a treatment for hypertension. It's proven to be as effective as blood pressure medication!
Surprisingly, it can take months of breathing better for the benefits to show up in your nervous system. It has to be more of a daily habit than an occasional exercise, which corresponds to my experience.
It took weeks before I could control my HRV to turn the emWave2 light green. After using it daily for a month or more, I learned to recognize the sensations regardless of if I was using the device or not. I eventually learned to intentionally slow down my typical breathing rate to optimize my HRV. The balance of my SNS and PNS nervous systems improved which eliminated my anxiety attacks.
Note that the rate found in healthy modern subjects is between 10-20 breaths per minute. So the 5.5-breaths-per-minute pace is surprisingly half the lowest rate documented in healthy people nowadays. Studies from before the 1950s found Americans breathing much closer to this slower pace.
The breathing ratio of liters of air per minute at rest is called the tidal volume (VT). Studies in 1929 and 1939 found subjects breathing around 5 liters per minute at rest. A study in 2005 found men breathing around 8.5L per minute.
Studies have also addressed HRV biofeedback directly. Improvements to subjects' parasympathetic and sympathetic nervous systems happen in addition to changes in breathing habits. So there's still more going on here that we don't yet fully understand.
Technically, no. The emWave2 isn't necessary to get these benefits if you understand why they happen. The health improvements mostly come from changing your breathing habits. You can do that without the device. But I think this invention is still worth the investment to help develop optimal breathing habits.
I couldn't have made these changes to my breathing habits without my emWave2. Even having something to beep and blink helped make it more like a game, and that motivated me to use it.
I learned to sense the feeling of my SNS being too active. I wouldn't have understood what that meant before. I would have thought it was nonsense. Who knew the balance of my nervous system could be objectively measured?
Since I have learned to recognize the different states that correspond to the data tracking of my high or low HRV, I can now easily predict whether the emWave2 will show my current state with a red or green light. So when I feel like I’m in the red, I notice it right away which allows me to begin resetting my breathing naturally.
I learned how those feelings differ from merely having a fast or slow heart rate. My mind can feel stressed and anxious even with a slow heart rate. Or it can feel calm and in control with a fast heart rate.
I can adjust my breathing to change that feeling depending on my heart rate at that moment. I can fine-tune my breathing thanks to the second-by-second feedback of the emWave2. I couldn't have done this otherwise.
If I have recently been moving around then a rate closer to six breaths per minute works best. If I have been sitting or standing still awhile then five breaths a minute works better.
I also realized how crucial posture is. If I was slouching, nothing could bring me out of the red for more than a few moments at a time.
But if I stood up straight enough that my diaphragm was activating my breath, I’d see benefits right away.
Rolling my shoulders or craning my neck forward does not affect my HRV. Straightening my core so that the movement of my breath starts below my ribs makes an immediate difference.
I even learned to identify the feeling which indicates I'm about to go into the red. Pausing my breathing prevents this from happening. I can readily detect this feeling now, even without the device. But I wouldn't have learned that skill if not for the useful feedback from the emWave2.
To this day, I still benefit from using this device to check back in, allowing me to see the effects of my current habits.
The emWave2 packs a lot of functions into a small space. The efficient design is convenient once you get the hang of it. But most of the hardware does more than one thing. So it can be a little confusing to figure it out at first.
Notice the two bumps at the top and bottom ends of the pulse sensor. To turn it on, you press the bottom one for two seconds.
Once the lights come on, you have to stop pressing. Otherwise, it will turn back off.
Then you need to rest your finger over the sensor—the same button you just pressed.
If you tap the bottom bump at this point, it will increase the volume (or reset it to silent if it’s already at its maximum). But holding it in for one second will turn the device back off.
Tapping the top bump will cycle through the brightness settings, but holding it in does nothing.
There's also an infrared sensor you will clip to your ear lobe.
The light at the bottom of the device blinks each time your heart beats. That blinking light indicates the device is working. As long as it’s not blank or skipping heartbeats, you can ignore it.
The panel of lights in the middle performs two different functions. First, it guides you when to breathe in and out with a “wave” of lights flowing up and down.
Nothing in the manual explains how this works. It's supposed to be guiding you on when to breathe. But it also creates its instructions by measuring your current breathing pace. This feature seems similar to the RESPeRATE device approved by the FDA to treat high blood pressure.
As I'll explain in a moment, I got consistently good results from just listening to the guidance sounds the device makes. I highly recommend you do the same. So I never really needed to pay attention to the wave of lights.
Second, that same panel racks up “reward points” that you can keep track of throughout your session. Every ten seconds you spend with medium HRV or every five seconds you spend with high HRV earns dim bars of light that will stack up as they are received.
If you fall to a low HRV, your progress resets. When the dim lights stack up and reach the top, you get a distinctive reward sound and you earn a bright bar of light that stacks up at the bottom. So you can try to fill the whole row up with brightly lit bars.
The light at the top is the most important part once you’re using the device. But you don't even need to pay attention to this either. It makes different sounds to communicate the same information that the light does.
When your HRV is low, the light stays red and the emWave2 makes no sound. When your HRV is medium, the light turns blue and the emWave2 makes a high-pitched sound. If your HRV is high, the light turns green and the emWave2 makes a relaxing, low-pitched sound.
Connect the infrared sensor to your earlobe. Power the device on by holding in the bottom bump. Rest your thumb on the sensor. Then try to make the top light change from red to blue to green as the cue sound changes from silent to a high tone and then the relaxed, low note. The goal is to try to keep it there.
If your light is either blue (improved HRV) or green (optimal HRV), then every five seconds it will beep either the high or low tone to let you know your HRV level.
I found the best results, by far, from breathing along with the sound the device makes. What I discovered works best is to breathe in, then pause until I hear a sound. Then I breathe out and pause until I hear a sound from the device again.
Interestingly enough, the HeartMath Institute thinks you should raise your HRV by thinking happy thoughts. Therefore, it would seem to be a sheer coincidence that the device registers a sound every five seconds because they don't tell users to breathe along with the tone as I have learned to do.
Yet research proves tremendous benefits to breathing between five to six breaths per minute. It just so happens that this pace equals five or six seconds for each inhale and exhale. This rate is the key to reducing anxiety and anger as well as reaping all the health benefits of optimal oxygenation of one’s organs.
The emWave2 also comes with a program that lets you play a few different games, as well as track your progress over time. These are interesting, and mixing it up is an effective way to keep motivated to use the device.
One game has you raising your HRV by lifting a hot air balloon into the sky.
You can also watch your raw data unfold in real-time.
You can track the changes in your scores over time.
There’s also a manual and video tutorials.
I find that concentrating too much on anything external, like raising a hot-air balloon, makes it harder to improve my score. The non-intrusive sound the handheld device makes is sufficient for me to be guided by it with my eyes closed. It’s easier for me to make rapid progress that way because I can pay closer attention to my inner sensations as I’m using it.
Don't get me wrong. The games and stats are all novel features. I'm glad that they're there, and I'm sure some people will enjoy them. But the most important thing is the real-time feedback on HRV. In my eyes, everything else pales in comparison to the value of that feature.
The health problems that result from exposure to stress are more within our control than we think. The external event that triggered our stress response might not even cause most of the resulting health problems. We might be doing most of it to ourselves by adopting bad breathing habits in response to stress.
Everyone experiences periods of anxiety or outbursts of anger. Both result from an overactive sympathetic nervous system. Practicing with the emWave2 can help retrain this SNS overactivation, which is the root cause problem. It can especially help those whose symptoms are frequent and severe.
Everyone experiences stress. In my opinion, the emWave2 can help manage it more than any other single tool.
Heart disease is the number one leading cause of death around the world. Training yourself to breathe better with the emWave2 can reduce your risk. It can do this by expanding blood vessels, boosting heart rate variability, and increasing oxygen delivery throughout the body. Those benefits likely decrease your risk of many other illnesses as well.
Some may not want to spend $199 on something so small with such a minimalist design. Those people should know that making a habit of taking only five to six breaths per minute would bring them most of the benefits. They can do this part for free and even use a free app to pace their breathing and build good habits.
Yet the ability to feel that and see it with the emWave2 helps you prove to yourself that you're doing something productive that results in quantifiable improvement. That makes the habit-building much easier. Also, the instant feedback helps you fine-tune your breathing to your unique physiology over time.
The emWave2 gets the highest recommendation I can give any product. Use it to design better breathing habits for yourself to reduce anxiety, anger, and the risk of everything from heart disease to diabetes. I believe everyone would benefit from spending at least a month using the emWave2 daily.
You can learn more about the emWave at HeartMath.com
This is a post by Aedon Castiel. Aedon is immersed in the world of biohacking, breath work and meditation and is a science writer Alexfergus.com
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