Overnight HRV versus daytime

Mine is similar to that - during the night it is around mid 30's and can hit peaks of 80 

Not sure if you have read this article also.

https://www.garmin.com/en-US/garmin-technology/health-science/hrv-status/

www.myithlete.com/.../

Just FYI, seeing your baseload is not long enough yet , I have found that the trend of HRV is very reflective of what my body is doing. For instance late last week I picked up some virus and the HRV noticed it and the trend went down quite a bit , its now slowly turning back as the situation has righted itself

Thanks! Will look through those links...

That makes sense. I'll give it a little longer to settle. I'm happy with the spot HRV checks (80s, 90s, more than acceptable) but the overnight is depressing!

2006309 said:

I'm happy with the spot HRV checks (80s, 90s, more than acceptable

I don't quite understand this statement. Raw absolute values are meaningless in isolation. What is important is the trend. From that perspective, unless you track your RMSSD snapshots *changes*, not values,  you are better off using the night HRV. Given the challenges of measuring HRV with a wrist heart rate monitor, Garmin has created a terrific user experience with that metric. As you can see, the night HRV varies a lot. Looking at the trend of the nightly average is a great approach and will be enough to optimize your training given your health and stress conditions (which Garmin does through the training readiness).

I'm new to HRV and just thought the higher the better, and was therefore happier with the higher values on doing a health snapshot versus overnight that's lower. What you say makes sense. I'll wait to see the trend and wait 3 weeks to get some data...

2006309 said:

just thought the higher the better

Yeah, it is a common belief and it is generally true. Higher HRV is a sign of less stress but it is in comparison to previous values. Although you see studies pointing at higher HRV with younger people, it doesn't make sense to compare HRV values with somebody else. Also, higher HRV can just be a rebound after an extensive period of high stress as the body would "give up". Vice versa, a lower HRV is a sign of higher stress, training impact, illness or too much alcohol, it is not necessarily a bad sign. Training will depress HRV and will not necessarily impact performance.

https://simplifaster.com/articles/interpreting-hrv-trends-athletes/

Training optimization using HRV monitoring works because it allows for individual optimization:, studies have identified significant improvement in training effectiveness when compared to traditional block training.

"The present results suggest that block periodization of HIT is an effective way to improve endurance and running performance in a short amount of time in already endurance-trained males. Individually HRV-guided timing and the number of HIT blocks seem to provide greater endurance and neuromuscular adaptations compared to predetermined training. Individually guided training may reduce the risk of overtraining observed as positive changes in HRV and serum testosterone concentrations. Both baseline heart rate variability and testosterone levels may be associated with the capacity of an individual to adapt to intensive block training."

 https://www.thieme-connect.com/products/ejournals/html/10.1055/s-0043-115122 

While it is possible to track HRV trends manually with the health snapshot or 3rd party apps, there are so many factors influencing this metric. Therefore the inclusion of HRV trends in training readiness is the right level of abstraction and simplification.