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The first scientifically validated Heart Rate Variability (HRV) app. HRV4Training provides HRV based insights to help you quantify stress,
better balance training and lifestyle, and improve performance. HRV4Training does not require a heart rate monitor, since it can accurately assess your HRV using the phone's camera.

HRV4Training also works with Apple Watch, the Oura ring and all compatible Bluetooth SMART sensors.

HRV4Training is also the first app that goes beyond simple measurements and provides insights on:
1) acute or day to day HRV changes in response to different stressors (alcohol, travel, sick days, training, menstruation, etc.)
2) long term multi-parameter trends to look at the big picture
3) correlations between physiological measurements and annotations
4) training load analysis, fitness, fatigue, readiness to perform and injury risk
5) VO2max estimation for runners linking the app to Strava or TrainingPeaks and using a heart rate monitor during their workouts
6) Training Polarization analysis (or 80/20)
7) Lactate Threshold Estimation for runners linking the app to Strava or TrainingPeaks and using a heart rate monitor during their workouts
8) Weekly and monthly summaries to track progress.

All data is processed inside the app in order to provide you with actionable interpretations that can help optimizing your training plan and performance.

Supported devices for the camera measurement: iPhones 5, 5S, 6, 6S, 6+, 6S+, SE, 7, 7+, 8, 8+, X, XS, XS Max, XR, 11, 11 Pro, 11 Pro Max

Currently unsupported devices for the camera measurement: iPhones 4S, iPads and iPods - These devices require a chest strap.

Other features:
- HRV-based advice helps you to adapt your trainings based on objective measures of recovery
- TAGS: lets you tag your sleep, mental energy, muscle fatigue, stress and all other parameters that can help you understand what is influencing your physical condition and physiological stress
- Works with Bluetooth SMART heart rate monitors (a Polar H7 is recommended) or simply your phone's Camera
- Integrates with the Health app (writes heart rate, and sleep, read sleep time)
- Configurable test (single or orthostatic, choose test duration between 1, 3 or 5 minutes)
- Extracts and stores the following features while lying down and/or standing: heart rate, mean of beat-to-beat intervals (AVNN), standard deviation of beat-to-beat intervals (SDNN), square root of the mean squared difference of successive R-Rs (rMSSD), number of pairs of successive R-Rs that differ by more than 50 ms (pNN50), low frequency power (LF, 0.04-0.15 Hz), high frequency power (HF, 0.15-0.40 Hz)
- Shows the PPG signal view to ensure signal quality during the test if the camera is used instead of a bluetooth SMART sensor
- HRV4T Recovery Points to provide a single, straightforward metric to analyze your physical condition
- Population summaries and people like you comparisons to put your data into perspective
- Analysis of compliance and consistency
- Data export via email or Dropbox
- Integrates with TrainingPeaks, SportTracks, Genetrainer and Strava

HRV4Training requires to register an account with your email address, so that your data can be backed up safely and retrieved in case anything happens (app issue, changing phone, etc.).

What’s New

Version 7.7.0

* minor fixes and improvements


If you like the updates, please take a few minutes to the review the app. It makes a difference. Thanks!

For any issues, contact: hello@HRV4Training.com

p.s. let us know if you'd like to experiment more. Happy to send you Camera HRV for free.

Marco & Ale

Ratings and Reviews

3.7 out of 5
138 Ratings

138 Ratings

the big swede ,

Changing Review after frustrated uploads.

I’ve been tracking my data for 14-15 months now. My workouts are uploaded from Training Peaks or Strava, but those apps lean heavy toward triathlon training.

I am not focused on triathlons, so many of my workouts do not register in Training Peaks and therefor do not register on HRV4Training. Also, hard to recognize overall or individual sport body-stress/recovery as HRV4TRAINING doesn’t separate different daily workouts. (If you run and then later in the day ride a bike, HRV4T registers it as a brick Run/Bike workout - not always the case).

Considering seeking a new platform.

Developer Response ,

hi there, thank you for your message and feedback. As you can imagine we cannot respond for Strava or Training Peaks :) We do read however most workouts, not only triathlon training. While in the app you have 1 main activity type, and triathlon combinations, we do read also all the other ones, you can verify this under History, by tapping the workout icon. You'll see there multiple workouts, of different kinds as well. An additional note which is important in the context of interpreting data: note that what matters here is the overall stress you put on our body, and the different stressors cannot be separated, so when we measure in the morning, we measure the overall stress which comes from all our trainings, and not only training as a matter of fact (for example stress coming from other aspects of our life). This is also the reason why there are metrics that try to capture overall load independently of the sport, and that can include already both intensity and duration, for example TSS. It's more important to try to capture overall load this way, maybe with a metric that works well for you, than to have a complete list of sports and activities. RPE could also be used as a overall RPE of our day, which will reflect in our physiological stress level. In this way, we can explore the relation between load and physiological responses meaningfully. - hope this helps, and please next time shoot us an email, it's easier to help you out that way. Thank you.

Beekaytab ,

The best app out there for HRV!

What can I say I’m impressed. I’ve tested and downloaded several other HRV apps but they either required an external or didn’t support the new Apple Watch feature that supports HRV. Even though this app doesn’t support the Apple Watch either, it still offered the ability to use my existing iPhone. Don’t be fooled, the iPhone camera works just as great. I used to use the camera for other things to measure HR and I found it to be just as accurate. The HRV was spot on at least referencing against the Apple Watch readings.

As for the app, there are some bugs that I’ve worked with Marco to resolve so while minor he has worked with me. I do acknowledge that most of these HRV apps tend to favor runners, cyclists, or triathletes. Fitness and CrossFit folks are just as interested in peak training. Remember us too!

Lastly, the insights are great and this is the kind of easy advice I was looking for. Integration with other apps to include Strava and Training Peaks is a plus. A negative is the inability to get into the weeds with your data or edit but I just found out they have a Coach app that will allow you to do that and I might have to investigate that!

Overall very impressed and hope they keep developing this app.

SydneyBristowSuperSpy ,

Disappointing $10

They sensor on the Apple watch has been proven to be accurate. (Yet no watch integration) A cardiologist actually laughed at the fact that this app uses a camera. We measured simple heart rate and found this app to be extremely off base. If it uses heart rate as a measurement in the hrv calculations, but it can’t accurately measure that, then how can they claim any accuracy at all?

I appreciate the response. Maybe it would be helpful to inform users before they buy the app that to get a true measurement, you need to have a Bluetooth monitor. Also I will add that I did not say anything about the health app measuring hrv. I just said that when i discusses it with my cardiologist, the cardiologist and I checked the heart rate before and after a stress test on my watch and then tried the hrv app with the camera. HRV4Training was very inaccurate. (If I can’t get an accurate bpm from your app (it was generally at least 20 bpm or more off while measuring with optimal connection) then how can it be trusted to measure R-R intervals?

Developer Response ,

hi there, thank you for your message and sorry to hear about the trouble you have experienced with the app. I would like to point out that it is not true that the Apple watch is an accurate sensor for HRV analysis, and even when it behaves correctly (for example for average heart rate under certain circumstances), it cannot be used for HRV analysis. It is important to understand that the Apple watch cannot be used as a regular sensor (like a chest strap via Bluetooth), as it does not comply to standard protocols, and beat to beat data cannot be transmitted or read (same for raw data). Apple recently added SDNN as an HRV feature that is written to Health from time to time, this feature is not representative of parasympathetic activity, or in other words of physiological stress, and is not very useful unfortunately in the context of short (1-5 minutes) physiological measurements. Additionally, the HRV value is written completely out of context (at random times of the day), hence what is measured is simply the effect of acute stressors or external transitory stressors, which are not really what we are interested in. When using HRV4Training, we try to capture baseline chronic stress, with a measurement clearly contextualized as taken first thing in the morning, before we are affected by other acute or external stressors. Please note also that while there is absolutely no validation of the Apple watch as a device able to measure beat to beat heart rate (RR intervals) and HRV correctly (and even on heart rate literature is conflicting), we did validate our technology, and your cardiologist might be simply misinformed or not up to date on the latest technological developments. This is normal, as this is a new mean to use this technology, but I would maybe ask or read a little more before taking that comment as an absolute truth (or simply ask us!). PPG from cameras has been used for decades, and right now is simply easier to do given the improvements in mobile phone technology. You can check this publication for more details: https://www.researchgate.net/publication/315059917_Comparison_of_Heart_Rate_Variability_Recording_With_Smart_Phone_Photoplethysmographic_Polar_H7_Chest_Strap_and_Electrocardiogram_Methods - Finally, should you have an interest in learning more about the physiological underpinnings of HRV, available technologies, best practices and applications, I put together this deck recently that I hope you can find useful - unfortunately there is still much confusion out there: slideshare.net/marcoalt/heart-rate-variability-technology-and-applications?trk=v-feed - Next time you have concerns or doubts, please contact us as we do our best to answer to everyone and explain these different aspects. Have a nice week.



A.S.M.A. B.V.
24.4 MB

Requires iOS 8.0 or later. Compatible with iPhone 5S, iPhone 6, iPhone 6 Plus, iPhone 6S, iPhone 6S Plus, iPhone SE (1st generation), iPhone 7, iPhone 7 Plus, iPhone 8, iPhone 8 Plus, iPhone X, iPhone XS, iPhone XS Max, iPhone XR, iPhone 11, iPhone 11 Pro, iPhone 11 Pro Max, iPhone SE (2nd generation), iPad Air, iPad Air Wi‑Fi + Cellular, iPad mini 2, iPad mini 2 Wi‑Fi + Cellular, iPad Air 2, iPad Air 2 Wi‑Fi + Cellular, iPad mini 3, iPad mini 3 Wi‑Fi + Cellular, iPad mini 4, iPad mini 4 Wi‑Fi + Cellular, iPad Pro (12.9‑inch), iPad Pro (12.9‑inch) Wi-Fi + Cellular, iPad Pro (9.7‑inch), iPad Pro (9.7‑inch) Wi‑Fi + Cellular, iPad (5th generation), iPad (5th generation) Wi‑Fi + Cellular, iPad Pro (12.9‑inch) (2nd generation), iPad Pro (12.9‑inch) (2nd generation) Wi‑Fi + Cellular, iPad Pro (10.5‑inch), iPad Pro (10.5‑inch) Wi‑Fi + Cellular, iPad (6th generation), iPad (6th generation) Wi‑Fi + Cellular, iPad Pro (11‑inch), iPad Pro (11‑inch) Wi‑Fi + Cellular, iPad Pro (12.9‑inch) (3rd generation), iPad Pro (12.9‑inch) (3rd generation) Wi‑Fi + Cellular, iPad mini (5th generation), iPad mini (5th generation) Wi‑Fi + Cellular, iPad Air (3rd generation), iPad Air (3rd generation) Wi‑Fi + Cellular, iPad (7th generation), iPad (7th generation) Wi‑Fi + Cellular, iPad Pro (11‑inch) (2nd generation), iPad Pro (11‑inch) (2nd generation) Wi‑Fi + Cellular, iPad Pro (12.9‑inch) (4th generation), iPad Pro (12.9‑inch) (4th generation) Wi‑Fi + Cellular, iPad Air (4th generation), iPad Air (4th generation) Wi‑Fi + Cellular, iPad (8th generation), iPad (8th generation) Wi‑Fi + Cellular, iPod touch (6th generation), and iPod touch (7th generation).


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  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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