HRV dropping fast

It is common for the HRV to drop in winter time compared to summer time. This time of year is also known for a lot of people being slight sick. That makes the HRV drop significantly, along with increased stress and resting heart rate.

What about your training load? Not overloaded? Not under-powered? My HRV seems to be very stable on optimal load last 4 weeks.

My load has been pretty consistent really. I’m not competing till next year so I’m floating between maintaining and recovery. Thanks for asking 

I’m hoping there is some truth to this winter seasonal thing otherwise I’m at a real loss

im finding the watch quite stressful lol too much body battery, sleep scores etc going on

It's OK to have some days or maybe weeks witch lower HRV, many factors can impact this. So i would say - don't mind and take it easy. Can be that garmins algorithm fitting not everyone. Maybe it was the last FW update... Who knows. 

I am confused about HRV readings from the first week. When I bought the Forerunner 255, it used 3 weeks to learn the baseline before the HRV feature started working. Did you have a different Garmin watch before, inheriting the baseline?

6276888, thank you for the thread, and you are not alone. I have observed my HRV dropping by about 10pts (same as you) over the past 2 weeks or so. Therefore sleep scores have been going down, from normally 85-90, to 70-80 now, the stress element being evidently critical in sleep score assessment. I have also observed a higher resting HR (both at night and by day) by about 5bpm. 

This was getting me a little worried because I have atherosclerosis and got a stent 6 months ago so was wondering if something is going on (which it still could of course). I live in Hong-Kong where the weather is year-long relatively warm, but we still have some "sort of a winter" with temperatures dropping to +15-20c.

ovekvam, you have mentioned about the seasonality of HRV before. I did a little research just now and there is indeed some literature on the subject including clinical trials.

OP, for your reading pleasure:

https://pubmed.ncbi.nlm.nih.gov/10879418/

Also, this (although small) study seems to show that exposure to cold weather activates the sympathetic nervous system and therefore lowers HRV:

http://ijomeh.eu/pdf-60410-4824?filename=Heart%20rate%20variability%20in.pdf

ovekvam, the research I was able to find including the above 2, are proper, actual research (as in, not newspaper article or tiktok garbage), but, IMO it's not "fantastic" research. Do you have "better" research to share ?

I found the same as you.

Totally true, I have had the 255 since its release date and every winter I experience what you mention

I had this in the summer for about 5 weeks. Was actually training less and had no other real factors I think that could’ve caused it, ie external stress. 
There’s lots of information on YouTube on how to boost it. Breathing exercises worked for me. Inhale for five seconds and vice versa, for two minutes several times a day really helped. Also use now mouth tape when I sleep to promote more nasal breathing. HRV is now normal. 

Then it's not only me. In four weeks my HRV average has went from high forties to thirties, and the watch expects it to be between 44 to 60 for the HRV to be balanced. For the last two weeks my HRV is Low, and my training status is Strained... No changes in training patterns, the change is that temperature has dropped in the last weeks, the firmware update and I've had a cold but my status was strained before that, the cold made it even worse... now my HRV is low, by a lot, and it will be for some time till the algorithm adapts to the new values, which could take 1 to 2 months at this rhythm.

I guess the algorithm does not fit everyone...

Best,
Kurt.-