HRV recording

HRV (Heart Rate Variability) is an at rest measurement that measures the difference in time from one heartbeat to the next.  Surprisingly, the more variability there is, the more rested you are.  Turning this option on allows you to put on your heart rate strap (and of course allow the HR sensor to pair), then Menu>My Stats>Stress Score>Measure.  This is an "at rest" measurement, best done at same time in the morning after waking up for the day.  This is an independent measurement, not part of any activity or ride.  Previous measurements will appear in GC Mobile as Performance Stats>HRV Stress.

I did this for a few days and liked having the results, but I found it to be tedious to put on the chest strap each morning to measure.  So, this cost me several hundred dollars because it sucked me into buying a Garmin Instinct watch that does this automatically all day long.  It is referred to as "Body Battery" within the watch menu, but it is a measure I really like having.  Now I can see that after a very hard workout and a good nights sleep, that I still really have the "MTB hangover" I'm feeling, as per my HRV/Body Battery score!  As the day wears on, you see your Body Battery dropping.  It's good encouragement for me to get more sleep.

Thank you for your very detailed reply! However I'm not referring to this "on demand" HRV measurement.

In the Menu > Settings > System > Data Recording.of Edge 530, there's an option called "Log HRV".

In the manual it says "Log HRV: Sets the device to record your heart rate variability during an activity".

I enabled it to see what happens and could see the HRV recording in Runalyze but not in Garmin Connect.

So my question is, what is the purpose of this setting if it's not displayed in Garmin Connect? Is it taken into account

for some other metric?

Wow, I just went back to the manual, and you are correct.  But I don't understand it.  I as well have that option turned on, but I don't know if there is any output data or computations using it.  I thought HRV was an at rest measurement, so I don't understand the recording of HRV variability during an activity.  Hopefully someone else knows, because now I'm curious.

Here's an activity with HRV recording, in Runalyze

I'm not familiar with Runalyze, but see my post from a few minutes ago, it is used by GC for "Training Status".

It says you also need a power meter to get Training Status, which I do not have, so I can only see "7-Day Training Load", but I get "No Status" on for Training Status page since I don't have the power meter.

So it's used for the training load calculation. You just can't see the actual data. Nice find!

Sorry, I'm replying too fast!  Yes, that's where it is going.

Hey, thanks for pointing this out, I learned something today!