Mar 22, 2016

Tracking HRV with Garmin Watches

How to enable HRV tracking and analyze the data in SportTracks

We recently announced the ability to manually input Heart Rate Variability (HRV) and Resting Heart Rate (RHR) data into the newly-customizable SportTracks Health page. In addition, HRV data can automatically be included in the .FIT files from specific Garmin sports watches! 

If you have access to a Garmin 920XT, 910XT, fēnix 3, or a Forerunner 620, you can start tracking and analyzing your HRV data in SportTracks — but first you need to manually enable the recording of this data on your watch. Instructions are below...

Garmin 920XT, fēnix 3, and Forerunner 620

To enable HRV recording you need to do the following:

  1. Connect your watch to a computer with the supplied USB cable
  2. Download this file
  3. Put that file (which is named “”) into your watch in this folder: :\GARMIN\NEWFILES
  4. Sync your watch with Garmin Express and disconnect

Garmin 910XT

To enable HRV recording you need to do the following:

  1. Power up your 910XT
  2. Press the Menu button
  3. On the Menu screen, press the Up button then the Down button, and repeat this ten times. 
  4. After pressing Up and Down a bunch of times, the watch will display its Diagnostic Menu. In the top right, select HRV to enable it.

Turning on this feature will eat a little more battery life than usual and make your FIT files noticeably larger, but it’s worth it to reap the benefits of HRV training.

NOTE: Here is a SportTracks blog post that clearly explains the benefits of training with HRV.

HRV App for Garmin Connect IQ

If you have access to a Garmin watch that features Connect IQ, you can download and run the free HRV app, which provides a simple way to test your HRV. However, the HRV data created by this app is not sent to SportTracks for analysis on the Health page. The current Garmin products that are compatible with Connect IQ are the 920XT, 920XTJ, epix, fēnix 3, fēnix 3 HR, the vívoactive, and the D2 Bravo.

Is there another way to measure HRV?

We highly recommend using the excellent HRV4Training app, which is available on iPhone and Android. HRV4Training automatically sends your HRV and RHR (Resting Heart Rate) data to SportTracks, and it utilizes the built-in camera on your phone to take readings, so you don't need to use a heart rate strap.

The instructions for the 910XT were provided by

Article written by Sam Mallery, Director of Marketing, Zone Five Software Inc.


Ok. That was a major clarification. Does this mean that the HRV app is not necessary to collect HRV data?

The Garmin Connect IQ HRV App only provides a simple HRV test, and the data it creates is not sent to SportTracks for analysis. I just added a sentence to this blog post to clarify this point. Sorry for any inconvenience!

Having HRV functions on a sports watch is compelling, however, we presently think the most useful form of HRV training is to use a dedicated smartphone app to collect this data. If you use an iPhone, the HRV4Training app is a great choice, becuase it's so nicely designed  and you can easily enable auto-sync with SportTracks. If you use an Android device, we presently don't have an HRV app partner that you can use, but, this is something we are actively working on.

Good. Will try it out tomorrow morning.
If my Fenix 3 HR collects data while exercising there should not be a problem using my cheststrap as I usually do.
Will report back after a few exercises

Hi, I have enabled HRV on my Garmin Forerunner 620. But how do you want me to track? Just as part of my runs...or measuring when resting? BRG Michael

Hi Michael,

We have a blog post dedicated to this subject called How to Train with HRV

One of the reasons why HRV tracking is a "hidden function" on watches is that the data isn't terribly useful if you're collecting it in an uncontrolled manner. HRV data is far more useful when it is collected during controlled, intentional tests.

That's why the most effective way to train with HRV that we have found, presently, is to use mobile apps. If you have an iPhone, we recommend using an app called HRV4Training (becuase its HRV and RHR data can be auto-synced to the SportTracks Health page — plus, it's just a nicely designed app). If you use an Android phone, we currently do not have an sync partner for SportTracks (but we're working on it). An Android app called "ithlete" is a good way to go.

Thank you for commenting!


Thanks for quick reply! I have Samsung/Android, I bought ithlete and ordered their finger sensor - hopefully you will get the integration, so we Android users can enjoy Sporttracks equal. Thanks

Hi! Is there a way to filter data by device/source? Well, my Garmin 920XT records HRV data during actvities and I use HRV4Training in the morning. Due to different scale of both values (approx. factor 10) data/graphs are quite "useless". If I could filter by device/source I could see e.g. HRV4Training data only which would give "better" results. Thank! Olly

There is not a way to filter your HRV data. We recommend only using the HRV4Training app. You should remove the HRV function from your Garmin watch, so you only see data from the HRV4Training app on your Health Page. This may require you to do a factory reset on your watch.

Sorry for any inconvenience!

I am now using the HRV4Training app and get my HR and HRV data in SportTracks. This is great.
But SportTracks has a couple of old bad HR measurements in this database, which give me a strange chart.
How can I delete those?

Hi Seb,

We have an editing feature on the Health page that enables you to rectify this issue. Basically, you just locate the HR measurements that you don't want (using the "All," "Year," "3 Months," "Month," and "Week" filters at the top of the page may be useful for this).

The data you want to get rid of is likely in the "Heartrate variability (HRV)" or "Resting heartrate" charts (or both). Hover your mouse over the bad data, then click and drag over the section you want to edit.

When you release your mouse button, a window will appear listing the individual values for each date within your selected interval. On the right side of the date list, you'll see a pencil icon to edit the data, and a trash can icon to delete it. I think this should help you get it sorted out.

Thanks for commenting!


Clear... And its works! Great stuff.
Thanks a lot Sam

I have a Garmin FR 630 and have enabled the HRV recording as described in this article through the 'hack'. I can see it's working when I directly upload the file from my FR630 to SportTracks Mobi, but normally I am using ST3 and then synchronize with SportTracks. In that scenario I cannot find my HRV data anywhere and it also does not show up in SportTracks, so I am wondering if there is anything I can do within ST3 to store and use the HRV data in there.
Any support / feedback would be very welcome.

I enabled HRV training on my 735XT putting that file into the new files path. Additionally I installed HRV4 and sync it with Sporttracks.
There is one big issue: There seems to be a factor 10 between the data gets from the watch (the values are at about 80...) and HRV4 (at about 8, which should be correct).
Any ideas?

Additionally: is there a way to erase the HRV functionality from the 735XT without resetting the watch (so that I could use HRV4 stanalone)? There was a suggestion for a solution that I should delete the file from 'Newfiles', but there isn't a file in that path any more....

Thank you for an answer in advance,
best regards, Axel

Any Ideas?

Question, my account is being populated with HRV data from measurements on my forerunner 935, I've been doing the HRV test on the watch, but also have HRV recording enabled for the activities. Is it possible to tell where the sportracks data is coming from? The Garmin HRV test, unfotunately, only gives a report on a 1-100 scale, doesn't seem to expose any actual details to the end user.
(I'd been using the HRV4Training app prior to this, which is a great app - but using the watch is a little more convenient.)

There is a file you can download from fellnr to disable HRV on Garmin watches in the same manner that you enabled it. I'll link to the page, rather than the file directly. Scroll down and find the "" file.

Thanks to HealthFit, you can now start tracking and analyzing your HRV data in SportTracks with your Apple Watch.

I'd like to understand the tracked data in detail. When I print a training's FIT file in php, I find an array hrv with data for each second of the activity. For each second there are five data entries. Does anybody know the meaning of these five values?

A typical data entry looks like this (for t=3060s):

[3060] => Array(
[0] => 0.407
[1] => 0.407
[2] => 65.535
[3] => 65.535
[4] => 65.535

The first two value are RR distances in seconds, but which meaning do the other three values have? Are they placeholders or some arbitrary values when there are no further RR distances in this time interval?