Regarding reliable ways to measure HRV in an ambulatory setting.
What I’ve found so far is:
The ECG necklace - price is between of €875 to €2500 ($970 - $2784 USD)
Various chest straps, such as Polar H7 (just $45 USD) - these seem to be uncomfortable to wear for extended periods of time, but the price is great. Plus others, like the OmegaWave, Wahoo TICKR, Garmin strap, Suunto, TP3 Transmitter, Zephyr, viiiiva… the list goes on, but again, all known to be quite uncomfortable.
ADDITION: @IoTool pointed out that the Zephryr BioHarness 3 (price presently $631 USD) is good for more than just RR intervals, it measures breathing rate, posture, acceleration, GSP - stuff that might add additional value. Plus it can be purchased pretty easily on Amazon, and worn as a shirt. The one downside (besides the price), is that it seems to have some shortcoming with slow data transfer.
Shirts with embedded ECG sensor. ADDITION: @ejain suggested Hexoskin - see below for details. Also the BioHarness 3 and others mentioned have shirt accessories.
Medical type wireless ECG devices, like the Actiwave Cardio, Equivital EQ02, Heartwing, Quardio, SEEQ, V-Patch) - prices are not online. One can only imagine how much these might cost.
ADDITION: @IoTool also suggested: The eMotion Faros with a price upwards of €576, the Shimmer3 ECG unit the price is €448 ($499 USD), and maybe you need to buy a dock as well, the VitalConnect HealthPatch ECG which also measures respiratory rate, skin temperature and body posture, the INeedMD EKG glove – the price of the latter two is not published online.
Pulse oximetry: On ear (like emWavePro), on the finger, or on the wrist (like smart watches) - but as I understand it, pulse oximetry is not good for HRV.
DIY: The Cooking Hacks e-Health Sensor Platform comes with almost every sensor you’d possibly want (SPO2, breathing, body temperature sensor, GSR + more) for €405 ($450 USD) - just the ECG would probably be cheaper. Looks really neat!
@shanusmagnus also suggested: Biosignal PI. I’m not clear on where you’d source the hardware components - it might take some hunting.
By the way, in my search I came across this recent article validating the Polar V800 with the Polar H7 strap, I thought it might be interesting to some of you who use it. Here’s the link: http://link.springer.com/article/10.1007/s00421-015-3303-9
The Hexoskin is as accurate as a chest strap, a bit more comfortable, and you have access to the complete, high-resolution data. However, it’s $400, and their latest version won’t ship until later this year.
We tested a lot of ECG devices integrated with our iotool.io smartphone IOT gateway. Results:
- Zephyr BioHarness3 - supported readings: best all rounder, 1 lead, textile electrodes or medical patch, other sensors, like activity, very reliable, decent battery life, offline download to PC, Bluetooth, sends data directly to iotool.io smartphone gateway. They also have an FDA approved device. We are using it in several healthcare pilot projects (like patients with CHF) and first responders. USA product.
- Faros Mega - similar as Zephyr, sends data directly to iotool.io smartphone gateway, The main difference: sampling frequency is lower, battery life is better because it uses BT LE, up to three channels. EU product
- Shimmer research ECG, more “researcher’s” oriented, only ECG, EU product
- VitalConnect HealthPatchMD, disposable battery and patch, USA product
- Other up to 12 lead ECG, like INeedMD (nice concept!) or Shiller - but they are made for more “hospital” or “niche” markets
We use all of that sensors on the field, so do not hesitate to contact me directly in case of any question
Thank you @ejain. Hexoskin looks interesting, I’ll add it to the list above in case anyone else is wanting to explore these options! Pity that the battery only lasts 14 hours.
May I ask what hardware you personally use on a daily basis with your own monitoring? Bet you have loads of personal insight! P.S. Zenobase looks really neat!
@IoTool – thanks very much Jure! Really great information! You really have reviewed loads of these products!
Zephryr BioHarness 3 costs a pretty penny (presently $631 USD) - but looks so good!! Out of the devices you mentioned, this one is probably most appealing to the majority of us on QS, particularly as it is a consumer product that can be purchased on Amazon. As you pointed out, it does a lot! Nice that it can also be worn as a shirt. The one downside (besides the price), is that it seems to have some shortcoming with slow data transfer from what I’ve managed to find online, but great for QSelfers who wants loads of datapoints.
The eMotion Faros series is intriguing. They can be worn in three ways, in a chest belt, used with disposable electrodes or as a self-adhesive patch – I guess you pay for these apart. Information on battery life not mentioned, and the link to the technical brochure is broken. For the cheapest setup, we’re talking upwards of €576 ($640 USD). Lacking published information.
The Shimmer3 ECG unit looks pretty basic but fine, the price is €448 ($499 USD), and maybe you need to buy a dock as well - this is not clear. Expected battery life is not clear either.
The VitalConnect HealthPatch ECG does more than just RR Interval’s, it also measures respiratory rate, skin temperature and body posture – really neat. Battery life = 3 days. Yet, no surprise, the price isn’t published online… I’m guessing upwards of $1000. Any ideas?
As you say, the INeedMD EKG glove and Shiller products are diagnostic/medically oriented - but look cool.
Thanks heaps for the information Jure! I’ll add it to the inital post for quick reference for others in the HRV search.
HI Amanda -
I spent a bunch of time looking for the same thing. I can confirm that the Actiwave is crazy expensive – on the order of $2k for the unit I evaluated. Dunno how handy you are with electronics (I myself am not at all) but I’m greatly intrigued by the development of an ASIC that is basically a one-chip solution to ECG ecquisition. This project includes schematics / plans / software for building a pretty badass rig using that chip:
I’m scheming to get someone to build a mobile of this for me.
Curious, is there someplace to get info about this next version?
@shanusmagnus Ouch, $2k - it’s just what I suspected though.
Love the DIY idea, that’s a really cool project. A while back I was seriously considering the Cooking Hacks e-Health Sensor Platform too, but I came to the same conclusion as you. Plus their reliabiliy is undocumented.
Maybe the DIY route should be put in the inital post too – I’ll add it now. Thanks for the link!
finnish companies seem to have some quality HRV hardware.
firstbeat offers the bodyguard 2, connected to the chest by ECG electrodes for data quality. for 24/7 logging (usb only, no realtime data transfer, also for sleeping, not for under the shower). 329 euros. used by professional sports teams and stress institutes and welness coaching. www,firstbeat.com
Technical specifications selection
Rechargeable battery (last app. 6 days)
Storage capacity: app. 20 days
Measurement accuracy for heartbeat recording: 1 ms (1000 Hz)
Data upload and battery charging is done directly via the USB-port
mega electronics makes several HRV sensors (was in the past the supplier of hardware for firstbeat, but more expensive)
www.megaemg.com has several types of sensors and other hardware. for logging and realtime measurement of HRV. also connected to the body with ECG electrodes and possible to use while sleeping. from about 500 euros.
cosinuss one. www.cosinuss.com. german company that uses an ear sensor. 100 euros. the sensor can also measure body temperature, and some other things.
research paper of in-ear hrv sensor (dont know if it is the same technology or not, german university)
This is a great list of ECG products to explore, thanks a lot for sharing all that info.
Stupid question: can you point to any “validated” device to measure ECG while sleeping in a regular and accurate way?
So a device that could be put on at night, every night for 100s of nights, and will give you FDA validated data (if I am correct that should be true bpm +/- 20%) with a relatively high data point frequency (very 1 min for example). Obviously with the data being recorded and accessible for later analysis.
This is to be used in a home setting, with something comfortable and unnoticeable to wear. So probably not a skin patch but more a strap. And something that can sustain many hours of body movements through sleep without becoming disconnected from the body.
I have a feeling the answer might be a multiple devices approach.
A problem with Bodyguard 2 may be the need for their software to access the device’s data, the data is $299 for one year. There may be ways around this(?).
Thanks, Mega is noted above (eMotion Faros). I hadn’t heard of Cosinuss! How interesting. I’ll see if I can find any more information on it!
Something tells me that that is not a stupid question at all. Might be difficult from consumer devices.
Surely someone on here has tried the same thing – hopefully someone here can help.
you are very welcome
firstbeat has free software to download the data from the bodyguard 2. its called firstbeat uploader and is downloadable from their website. (would google to find it. website looks beautiful but it is very difficult to navigate and find anything youre looking for). firstbeat uploader is used to upload to firstbeat with login (for paying welness coaches) AND for getting the files on your computer (without login; free)
if i am correct; cosinuss uses technology from a company called valencell http://valencell.com that licences out the technology to companies to build heart rate (variability) devices with. its technology is used in multiple in-ear headphones for sports usage like in iriver, lg, sony. see: http://valencell.com/customers/
the beauty is that it can measure much more then usual heart rate /HRV sensors. for deeper insight in their technology and functions http://valencell.com/patents/
you can look op the patent numbers through for example espacenet https://worldwide.espacenet.com/
I totally understand what you want. i think my quest for a HRV sensor was very similar. after a week of search i finally went for firstbeat bodyguard 2; there were some more interesting devices but they were out of my budget. i have no idea if i made the right decision but i made my decision after a week of searching and asking questions to suppliers/distributors of devices.
i understood that
- straps usually move during sleep, which makes it impossible to get good readings and electrodes stick very well even during very rough nights.
- devices using electrodes used for ECG with highly conducting gel are much more precise
- it is preferable to used devices with logging capabilities (memory, battery) over devices who send the data over bluetooth to for example your phone.
in medical settings, stress and sleep laboratories they therefore use mostly electrode based devices. firstbeat and megaelectronics specifically advertise with 24 hour measurements. which i have never seen with strap based devices like suunto or other heartrate devices using straps.
a message of warning:
if you want to log for 100+ nights. the ECG electrodes have to be changed every day according to the user instructions http://ambu.com/ldatasheet and they cost cost about 10 euros per 25 excl VAT. most devices using these electrodes use two per day
Thanks a lot for all this info, looks indeed like a consumer device approach to accurate ECG measuring is challenging.
Looks like there’s still lots of interest in wearable ECG and HRV. I’ve been extremely interested in this area for a couple of years, experimenting with a goal of creating low cost, open source hardware to make heart rate / heart rate variability measurement practical for any QSer who’s interested. To get accurate HRV (not just HR) on a human that is moving around, I believe you should use ECG electrodes, not optical plethysmography a’la Basis, Apple, Fitbit, etc.
I have a pretty good start on hardware and firmware for a Bluetooth Low Energy 1-lead EKG sensor. The parts and PCB can be built for under $75 (maybe under $50 in modest quantities). The firmware is written in Arduino code. It reads the EKG signal and does QRS-detection to pinpoint each heartbeat. There’s 128Kb of memory but it could be expanded (it’s plenty for average HR every minute, but if you want every heartbeat stored, you need more memory). As far as mobile apps – that’s not my strength, so there’s lots of opportunity there! This is not a commercial unit. It’s a volunteer-based, hacker-oriented, experimental device – no FDA approval sought or implied, no medical uses, etc. If you’re interested in collaborating, please contact me.
More info here and here
Thank you for your comment. Our free IoTool.io (a smartphone IoT gateway) supports more than 100 different wired and wireless sensors with more than 250 readings through powerful and flexible extensions system. In general for a new sensor we just need to write a small service which collect data from sensor. The service is simple and it can be make in a day or two (we can develop it or you). After that is fully integrated into the whole system (smartphone or Raspberry, Dashboard, Cloud). In this very moment we support a lot of HR sensors, but also ECG: Zephyr Bioharness, Vital Connect, Faros Mega, Shimmer research, Schiller, INeedMD…) and Arduino sensors (also with all Analog and Digital input).
To make a long story short: we are willing to contribute, either with documentation how to develop a sensor service or with our own sensor service. More on iotool.io. You may directly contact me to email@example.com
I haven’t used it myself, but another option is using a Polar H7 with one of these Adidas fitness shirts or bras by Numetrex. I would like to see whether someone could wear it comfortably all day.
I managed to get good readings ( one or two missed beats in 7 hours) during sleep using my polar H7 and a soft strap. I used conductive gel and over-layed a compression shirt to keep the strap from lifting off during movement. I analyzed the data using KubiosHRV software. I would not describe my setup as comfortable for extended wear and I have yet to achieve more than a small fraction of the predicted 300 hour battery life on the H7. I think you will want to use conductive gel with those Adidas shirts and they may still lose contact during sleep (specifically rolling on your side).