HRV-Stress Test reliable?

Just tried to use the test for watching my training/health level the past 15 days and figured out that it seems not to work. I use the Garmin Dual strap and when I do two test in a row I have one time a value of 54 and on the next test 98 just a minute later (well 4 min including the test) I guess if the test cannot reproduce the same values +/- 5 or 10% it is non sense. I could also throw a dice and say hey great today I am relax I should go for a hard training. Anyone experienced the same?

Guess the heart rate variability should not change within 3 or 4 minutes.

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HermanB over 5 years ago +7

Without trying to get overly philosophical about this there's a difference between data being accurate/reliable and data being useful/meaningful.

The HRV-Stress Test is a very good example of the difference…
gaijin over 5 years ago +3 suggested

I don't think the Garmin HRM-Dual is capable of delivering acceptable HRV data.

Here is a list of compatible HRV Heart Monitors from Elite HRV: Compatible devices for HRV

Note the Garmin HRM-Tri is…
Lens_osy over 5 years ago in reply to gaijin +1

Well that might be a explanation.

All Replies

0 gaijin over 5 years ago

I don't think the Garmin HRM-Dual is capable of delivering acceptable HRV data.

Here is a list of compatible HRV Heart Monitors from Elite HRV: Compatible devices for HRV

Note the Garmin HRM-Tri is listed, but the HRM-Dual is not.

If one searches on the Garmin site for specs, one will find the following notation for the HRM-Tri: "Supports heart rate variability and advanced heart rate features: yes" (Link to specs page: HRM-Tri Specs)

A similar search on the Garmin site for the HRM-Dual yields no mention of HRV support.

I would suggest using a HRM chest strap that fully supports the transmission of HRV data - your test results should be much more accurate, and repeatable.

HTH

0 TobiasLj over 5 years ago in reply to gaijin

Not sure but as far as I know the Garmin Premium strap (mentioned as compatible) was replaced by HRM Dual.

0 TobiasLj over 5 years ago

Lens_osy said:
Guess the heart rate variability should not change within 3 or 4 minutes.

It will unless you are really stressed. HRV is the variation of time between beats and the idea behind FirstBeats metrics for Stress is that you have a bigger variation when you are relaxed. Interesting theory, https://www.firstbeat.com/en/blog/what-is-heart-rate-variability-hrv/ and https://www.firstbeat.com/en/blog/what-is-stress-science-behind-all-day-stress-tracking/ will give you good info.

For me the stress test works. It is important that you perform the tests on equal conditions and that you do more than two tests to rule out tests that obviously isn't right.

0 pxl over 5 years ago

Well, while I have some issues with Fenix's stress measurement (sometimes it just starts to show a lot higher than normal and only a full reset solves the problems), but apart from this software bug, it really tracks accurately my stress level - and yes, it could change within minutes.

That being said, if nothing really changed between the measurements, probably it is hw issue. Did you compared the result to your watch?

0 morey000 over 5 years ago

1. HRV can absolutely change significantly just over a few seconds.

2. it's generally much more accurate to measure HRV with a chest strap, that detects the electrical impulse, than using a wrist based OHR. I'm amazed mine works as well as it does, although sometimes it can't get a reading. Guess it all depends on your expectations of it.

0 Simone.01 over 5 years ago in reply to morey000

@morey000 @TobiasLj @J

Did you usually do it while standing or lying down?

0 TobiasLj over 5 years ago in reply to Simone.01

I normally stand up. I always make sure that my heart rate goes down, that I feel relaxed and take a few deep breaths (breathe with the stomach) before starting the test.

0 Lens_osy over 5 years ago in reply to TobiasLj

I meant more the test results of the test than the HRV itself. So under same circumstances I expect similar results when doing two or three tests in a row which currently is not the case.

0 Lens_osy over 5 years ago in reply to gaijin

Well that might be a explanation.

0 morey000 over 5 years ago in reply to Simone.01

Simone.01 said:
Did you usually do it while standing or lying down?

hah- neither. sitting generally.

Saw a therapist demo HRV in front of a lecture room with a volunteer. he spoke to the woman and relaxed her- giving her calming thoughts- and displayed on the projector was her HRV, which got in sync. then- he said... now I want you to count backwards from 100 by 7's. Her HRV went from this nice sine wave to totally erratic in a matter of seconds. So- it's as much a matter of your metal state as it is your physical.

I had a stomach bug a few months back. Spent the day on the couch feeling awful with a mild fever. Even though I was physically relaxing, my HRV was a mess and my body battery went down to near zero.

So- HRV is a measure of 'stress', which can be from multiple sources.