When does HRV baseline reset?

Hi,

I've seen few posts about HRV trends going down (on Reddit). It isn't clear if something changed on Garmin's end but for me it exactly matched when I started wearing my new Fenix 8. I'm healthy, not sick, sleep as usual and train as usual. But I'm now 12 days in the "strained" status with no end in sight. It's really annoying because I'm in the middle of a plan and all the metrics are off (training readiness included since it takes into account HRV). Is there a way to reset the HRV baseline manually? It clearly measure slightly different than my previous watch. 

Thanks.

  • A couple more weeks will see it stabilize. FWIW mine plummeted a couple of weeks ago, does that every now and then, but it’s coming right now. 

  • Give it a bit more time. HRV is very sensitive to stress and other factors which can last 3-4 weeks easily. Adjusting baseline just because someone got covid and HRV tanked for 3 weeks wouldn't be the best approach as it will recover straight after in most cases.

  • Not sure if it's helpful, but I notice that your HRV trend was going down even before you upgraded to F8, quite drastically if I may add. If anything, the downward trend has slowed (it did not continue to drop at the same rate as before getting the f8, but slower). Changing to the F8 might not have anything to do with it, according to your data trends. 


    I would personally look elsewhere for answers, maybe recent lifestyle changes, stress, late dinners (by far the most critical factor affecting overnight HRV) and reduced recovery time after strong effort. 

    To answer punctually, no, there's no way to manually reset the HRV baseline to align to your "new" HRV averages. A period of two weeks for baseline adjustment was thrown around on the forums in the past, but it might be just speculation or hearsay. 

  • Thanks for the comment.

    That's the thing, I can't quite pinpoint the reason why. My workout intensity is the same, I feel great, sleep quality is nothing off the ordinary, I don't drink alcohol or eat late at night (we usually eat around 6/7pm), no change in my diet or medicine, no stress at work or in my personal life.

    I guess I'll have to live with the strained status for many more weeks if the baseline doesn't reset.

  • That's interesting, and I can relate to having all the variables under control, I sometimes find myself wondering why HRV is going down when everything is under control and has been the same. 

    My only thought would be that the body might be fighting off some minor asymptomatic illnes or a physiological process taking its toll on the body to combat an unknown stressor. Would you have the ability/time to go get your immune response checked? For example, a simple white blood cell count could highlight that something is going on in the background if the values are increased. Might be a quick lab visit and inexpensive procedure. 

  • Honestly I hesitated to even post this because I would hate for it to serve as a source of any anxiety but I was diagnosed with sinus cancer in late July and the ONLY metric I saw going astray was my HRV (As you can track above from a few months prior leading into July). After a month or two of treatment (I'm still going) it started to trend upward and return to a relative normal. 

    For reference im a 20hr/week cyclist pretty in tune with my physical self and didnt notice much if any other disruption to my norm during this until well into July. Obviously wrist-worn device metrics aren't in any way medical grade or always correct I wouldn't write it off if it continues to spiral especially if you have any other symptoms / weird things going on. 

  • A period of two weeks for baseline adjustment was thrown around on the forums in the past, but it might be just speculation or hearsay.

    From experience if HRV stabilises at a new 'low' then after a couple more weeks the baselines will also adapt. If however, the HRV starts trending back up again (see my graph above) then there will be little movement in the baselines. Overall, if the HRV settles on a new level it could be 4 weeks or thereabouts before the thresholds adapt.

  • That's the thing, I can't quite pinpoint the reason why.

    Probably just a seasonal change. HRV is not a constant value throughout the year, even if the level of fatigue or stress feels the same.