EmWave2 Heart Rate Variability Monitor

what is it, you ask? here’s a description from their website: emWave technology collects pulse data through a pulse sensor and translates the information from your heart rhythms into graphics on your computer or into easy to follow lights on the portable emWave Personal Stress Reliever. Used just a few minutes a day, this simple-to-use technology helps you transform feelings of anger, anxiety or frustration into more peace, ease and clarity.

i recently got this as i was curious to explore how it might complement + enhance my meditation practice. it was rewarding to have something so nebulous “quantified” by being shown the variations of my brain waves during meditation. however i found the device itself rather annoying to use and the software kept crashing my computer (i’m on a mac but in general they do support macs) so i ended up sending it back.

i think it would be most useful for someone starting a meditation practice or dealing with serious anger/anxiety issues. it’s pretty pricey at $250 but they do offer a 30-day return.

You may want to leave a review on the Quantified Self Guide page for the HeartMath Stress Reduction Tools as well.

I’m a certified Heart Math trainer / exec coach and gave a presentation on heart rate variability and stress reduction at the QS Conference. I’m also the former CTO and co-founder of Basis.

I am also an emwave distributor who offers a discount for QS people - contact via pm.

There are a few inaccuracies in Maybanks’ comments. First, the emWave PSR doesn’t do anything with brain waves. That requires EEG, which I have also used extensively.

HRV training teaches you to consciously modulate the spacing between individual heart beats so it is more sine-wave like and at a higher amplitude, which results in clinically proven health benefits. It is very good at balancing autonomic nervous system functioning. Most people today are sympathetically over-activated (fight or flight) and learning the Heart Math techniques (not just plugging it in to your computer and doing your normal meditation) has a repeatable, measurable effect on stress and executive performance.

In my 15 years of using electronic tools to biohack my own brain, I’ve found it to be the most cost-effective way to get the most benefits, showing many of the benefits of EEG training (but not all) that costs more than 15 times as much. That’s why I became Heart Math certified (I am a high tech VP cloud computing guy, not a therapist or something…)

Most forms of pranayama and meditation won’t work with a Heart Math device, which is why it can be frustrating for a new user who “knows” some meditation but hasn’t had any coaching. The only meditation forms that seem to work with the emwave are heart-opening forms of Buddhist meditation, which themselves closely resemble the Heart Math techniques. “Opening the heart” is actually something you can quantify, measure, and receive feedback on using heart rate variability. It’s profound that a device can turn green when you do it right, taking months off the time it would take you to properly learn the technique without feedback.

Secondly, the emwave is not $250. It’s MSRP is $229 and there are other prices available!

As to the computer problems, the devices work without being plugged in at all and store session data internally for later upload, or they work in connected mode. If you got the very first batch of emwave 2 devices manufactured, there were a few problems reported by isolated users. They have since been resolved according to the Heart Math people.

[quote]I’m a certified Heart Math trainer / exec coach and gave a presentation on heart rate variability and stress reduction at the QS Conference. I’m also the former CTO and co-founder of Basis.
[/quote]Will basis have a high enough sampling rate to measure heart rate variability?

dave, thanks for catching my error in saying it measures brain waves, of course i meant to say heart rate variability. and i can see that a new user would be much better served by having a coach to teach them how to get the most benefit from it. i was not intending to offend or pass judgement on the company or product, merely sharing my own personal experience of using it after being intrigued by what i heard about it at the recent QS conference.

You’d have to ask the Basis guys. When I was there, I thought it was a huge mistake when they made the decision to pull the HRV-enabling features I’d been pushing. Who knows, maybe they changed their minds.[hr]

Maybanks - I’m curious - it sounds like you were a new user to it, but the computer crashing problems didn’t help. How many actual sessions did you do before sending it back?

We have been dreaming about how cool it would be to enable people to collect HRV/cardiac coherence data as they go about their daily lives, and then later explore and reflect on the results along with other time-synchronized contextual data to help make sense of what was going on when. It’s one of the main types of data that we think would be high leverage for people using BodyTrack to understand environment/wellness interactions.

We’ve been wondering for a while whether the the Emwave2 has a real time clock and is able to log data with appropriate timestamps when away from the host computer. If so it has the potential to also be useable for our purposes. I expect that the data from the ear clip is noisy when the user is moving around, but we also intend to acquire accelerometry data which could help reflect when motion artifacts are likely.

Does anyone know if the Emwave2 could support this type of usage? If so, do you know if they can export timestamped data, and in what form? Do you know how long it can record for? We have looked for info at the Heart Math web site, but not found an adequate level of detail to be able to answer these questions.

The chest strap we’re building is designed to measure HRV/cardiac coherence, but we really wish there were a reasonably priced commercially available unit available that can do the job and do appropriate data export. The only candidates we’ve found so far (Zephyr BioHarness BT and the FirstBeat BodyGuard) are both ~$700, which is too expensive for our purposes.


I like the idea of using accelerometer data to highlight when noise would be at an increased level! The Zephyr HxM would probably be best for this since the accelerometer is integrated in the HRM.

You mention another very important issue - timing. Unfortunately most companies don’t provide their RTC accuracy, nor do they provide ‘event to measurement recording delay’.

Timing with microsecond or better accuracy will be necessary in the future to allow users to combine data from different devices and be able to tell a story from the data.

Luckily most of the HRM straps do send HRV data; however, most Heart Rate Monitors don’t record this data. Below is a list of other commercial and open source options that record HRV:

Commercially available units that measure & export HRV:
[]Polar RS800CX (~$350)
]Suunto T6d (~$320)
[]Suunto Memory Belt ($169)
]Polar Cycle Computer CS600X (~$290)
[*]Polar Team2 (pro system - very expensive)

Home grown options that require some user expertise to allow them to capture HRV:
[]Zephyr HxM ($99). Attach this to an android phone via Bluetooth, write an app and record the HRV values.
]ANT+ compatible HRM (Garmin) combined with an ANT+ USB Stick and open source SW/Linux allows you to record HRV
[*]Polar HRM combined with the Sparkfun Polar Heart Rate Monitor Interface and HRV recording software such as OpenZephyr

If you want to evaluate your HRV Take a look at Kubios - a free HRV evaluation tool.

hi dave, i used it most days over a 2 week period and have about 10 sessions that were 10+ minutes long; i finally figured out that it wouldn’t crash if i used it independently of the computer and then downloaded the data (when connected to the computer, the program froze most of the time i was running a session–their tech support suggested i use a different usb port and try it with bluetooth off, but kept having the problem). also after the first week i used it exclusively when meditating, and was getting to about 70% coherence on the lowest setting, so found it worked really well with meditation. (i did play with upping the setting and of course that was more of a challenge). if their return period was longer than 30 days i would have probably kept working with it longer but i didn’t want to take the chance of them not accepting it.

Hey Dave,

Is the emwave useful for measuring changes in the emotional state such as anxiety? Does it detect changes in breathing and body temperature?


The emWave simply measures the time between heart beats (HRV).

It does not evaluate emotional state, nor record temperature or breathing rate - although if you practice with it you will notice that you feel different (maybe even better) during coherence.

If you are looking for temp & breathing rate take a look at the Zephyr BioHarness

Hope that helped!

Jxa, it does a little more than that. There are 4 difficulty settings. Settings 1 and two measure straight HRV and train you to use it better. You can’t get higher HRV if you’re anxious, so by learning to raise your HRV, you reduce anxiety. Similarly, if you find it takes a lot of effort to enter HRV, you can deduce that you have anxiety, but it’s not as quantitative as I’d like. You can deduce breathing rate from HRV with 98% + accuracy if memory serves, and the breathing meter in Heart Math software uses that to guide your breathing to help you into coherence.

But in the higher two settings, as I learned in my training to be Heart Math certified, there is a little more to the algorithms. It’s proprietary (ie they didn’t tell me specifics) but from what they explained, and my own experiences, breathing synchronization just doesn’t turn the light green. It takes visualization techniques for me to get it right, and the injection of a “happy feeling.” If I do the breathing without inserting an emotion, it doesn’t work. How that’s quantitatively measured is the “secret sauce” of the emwave. However, the ability to learn to playback or induce a positive emotion on demand is amazingly helpful with anxiety and creating other high performance states.

I’d love a Zephyr Bioharness but you need the $700 one to get the real data. The $99 one claims to do HRV but I haven’t verified it, and it’s not clear which device you’d use to view it - maybe an Android tablet? A cool combo if you’re willing to wear a chest strap. I want one!

For forum readers, I’m a Heart Math distributor and if you want one, drop me a line and I will give you a discount code for QS people.


I agree emWave does more! I interpreted the question a bit differently than you - thanks for clarifying :slight_smile:

The HxM definitely measures HRV. I verified it using OpenZephyr + BT on a laptop.

Garmin HRMs send out RR data - Video, Code

I’m waiting for the latest BioHarness to come in - will let you know how good the data is when it arrives :smiley:

Thanks to Dave and JxA for the responses. Dave understood my very unclear question a little better :slight_smile: I know that emwave measures HRV, but from what I have read it seems that it indirectly gives feedback about anxiety levels and breathing rate. Dave, could you elaborate on these indirect relationships and how reliable is the feedback. Also, I think i read something about skin conductance sensor, is it not capable of measuring body temperature? My ultimate goal is to have a feedback on my stress levels while performing activities on the computer. I would like to know when my anxiety starts rising and then I would determine a level, where I have to intervene by focusing on my breathing and injecting logic. Best case scenario would be that I would have several cues that I am approaching this point such as changes in HRV, breathing rate and body temperature which I assume all correlate to anxiety levels. Dave do you think this is doable with the Emwave? Any other suggestions are welcome. JxA I would check all the links you have provided, thank you for them.

I’m following this conversation with interest, and thinking about whether we have the seeds of an HRV study group or collaborative experiment here. I would love to participate. This is an increasingly accessible, but still emerging tool for self tracking and there is a lot to learn.


I like where you’re going with this :slight_smile:

I’ve been thinking about this same subject. I’d like to use bio-markers to help me realize when I am being less efficient, frustrated, have bad posture such that it causes back/neck issues, learn when I do my best work so that I can know when I do my worst and focus there during design reviews, etc.

There is a QS video named MoodyJulio video that discusses something similar to what I think you are looking for.

Another option to collect the non-HRV data is professional version of the BodyMedia Device. The SenseWear Device - the outputs give me Galvanic Skin Resistance/Response, activity (accelerometer) and heat flux.

The BodyMedia device would be great if I could extract the data in a more real time manner.

I hope this helps![hr]

Gary - let’s talk more about this. I have ideas, but not resources at this current moment.

Funny enough, I just delivered a webinar to 120 people while wearing the emwave to see how my anxiety level was. I spent 70% of an hour in medium or high levels of coherence, which is awesome given that when you’re talking, you can’t breathe evenly, which is an easy way to get into coherence. The emwave absolutely works to monitor anxiety. I have also used it while driving (yes it’s safe, it’s hands free) and notice changes in my anxiety based on others behavior, although to be honest that is not a major issue for me anymore given some other brain hacks I’ve done.

emwave doesn’t have GSR (skin conductance) which isn’t as useful for feedback compared to HRV imho. It was just easier to do back in the day. I think the Scientology stuff is based on conductance but not sure. Looks like it anyway.

I can arrange a group discount (significant) if you want to do a study using emwaves.

[quote]emwave doesn’t have GSR (skin conductance) which isn’t as useful for feedback compared to HRV imho. It was just easier to do back in the day. I think the Scientology stuff is based on conductance but not sure. [/quote]Skin conductance is useful if you have a high sampling rate.
With machine learning it has an accuracy to identify positive vs. negative emotions with 80% accuracy.

Heart rate and skin conductance are both values where you learn a lot more when you have subsecond data and can run algorithms over it.

Ok, so:

1 if i hold my breath or do not breathe in normal intervals, my coherence will go way down

2 if I am stressed, angry, fearful, overwhelmed, excited my coherence should go way down (downside of this would be too many types(range) of emotion can cause my coherence to go down)

Please comment on these and correct where my understanding is wrong.

I’m pretty sure the Wild Divine device will measure both galvanic skin response and HRV, at least with the right software.
I’ve been looking into HRV measurement since the Personalized Life Extension Conference, (October 9-10, 2010).

One of the speakers gave a presentation on HRV - I believe it was similar to his presentation here - http://quantifiedself.com/2010/04/numbers-from-the-heart/

I can verify that the sunnto t6 series watches will measure HRV, and I’m really hoping the Basis will do the same.

Also, I’d be interested in participating in any HRV study.