|
Sep 2021
9:31am, 21 Sep 2021
4,235 posts
|
StuH
I always find my HR is lowest when my bowels are open. Just sayin...
|
|
Sep 2021
9:41am, 21 Sep 2021
991 posts
|
Sam Jelfs
The RHR reported by Garmin and the lowest reported figure are different.
The continuous heart rate measurement is done beat-to-beat (I think), i.e. it just converts the measured interbeat interval to BPM and reports it every beat.
The RHR is an average, I think the firstbeat method used by garmin averages over something like 50 beats after the lowest detected HR, but other ways are to use something like the lowest 5th percentile of the total recorded HR.
Basically if for one beat you drop to 30 bpm for some reason, but for the rest of the day you never drop below 50 bpm , you don't want to report that single beat outlier as the RHR, but it is the correct lowest measured point...
|
|
Sep 2021
9:50am, 21 Sep 2021
992 posts
|
Sam Jelfs
If you do the manual measurement when you wake in the morning, make sure you really do it as soon as you wake up.
High cortisol levels will increase your heart rate to some extent and the issue comes that aside from stress induced changes to cortisol there is also a slower natural cycle as part of your circadian rhythm.
There is a large peak in cortisol that is linked to when you wake up, the Cortisol Awakening Response, which tends to peak about 20-30 minutes after waking, and gradually decreases over an hour or more. It changes person-to-person, (and a low CAR can be a symptom of other issues), so how big the effect on HR is can be significant for some. So just laying in bed for 10 minutes can longer can give a very different measured RHR...
|
|
Sep 2021
10:30am, 21 Sep 2021
20,954 posts
|
Bazoaxe
When I have measured my RHR manually immediately on waking and also looked at my garmin I get about a 5-7 beats difference. High 40s v low 50s. The garmin does pick up a low of about the manual reading.
|
|
Sep 2021
11:17am, 21 Sep 2021
15,445 posts
|
larkim
I tend to wake up thinking about work and the day ahead, and it feels like the rolling around in bed to grab a watch and do the count etc raises my HR a little. Maybe (as usual) overthinking things.
Useful discussion, though - thanks all.
I'll keep track of Garmin's measurement as I get fitter, at least now I've got "something" consistently measuring a figure of some sort with a degree of consistency day to day.
|
|
Sep 2021
10:30pm, 30 Sep 2021
567 posts
|
tipsku
Very interesting discussion. Thanks for all your contributions.
Since getting my FR 745 last year in November, I've been measuring 24/7, also when I'm asleep. Garmin gives me 2 minute averages throughout the night. The lowest I've seen in the 2 minute averages is 39 several times. For the RHR average, it usually gives me a number 2-4 bpm higher than then lowest 2 min average. So there could be lower outliers but since I can only see those averages, I think they are fairly accurate.
When awake, lying on the sofa, the lowest readings I've seen were a few beats higher, 42-44. Sitting in a chair is a few higher again, 45-48 when I'm not doing anything else. Just extending the arm to grab a glass of water raises it over 50.
I use the RHR averages to determine whether I'm ready for hard training sessions or if it's better to stick to base training (MAF) only for the moment. I've been training for fast times since January and improved quite a lot (4 minutes of my 10k time) but I think I'm done for a while after 9 months. After a couple of weeks with RHR averages 45-52, I've concluded that I'm too stressed and I'll stick to low HR for at least a month to see if things improve.
|
|
Sep 2021
11:27pm, 30 Sep 2021
23,543 posts
|
Dvorak
Whilst not disputing the physiology of what Flatlander says, it doesn't tie in my my own experience. I got 52 tonight - yes, watching the football - but I'm never seeing the 46-48 in the morning that would suggest. In fact, for fair chunks of the asleep time, the Garmin is typically recording 56-60. I recorded 51 today around 1pm - in the middle of an eye test.
Last seven days rhrs shown on Connect, backwards from and including today: 58 43 61 60 52 56 54
(Yes, that 58 for today is rather more than the 51 on the graph.)
|
|
Oct 2021
11:28am, 5 Oct 2021
15,623 posts
|
larkim
Just another post from me to report the "spot on" wrist HRM tracking I'm getting. Whenever I've worn the Polar OH1+ and the FR645 together the HR tracks have been identical when comparing the output graphs post run.
The only reason I'm posting it is that optical wrist HRMs have had a bad rap (?) for a while, especially when running, so I'm pretty delighted that I can ditch the OH1+ and just rely on the watch.
|
|
Oct 2021
11:32am, 5 Oct 2021
35,401 posts
|
SPR
I think the issue is your experience doesn't mean it is universal and it will still be flaky for many.
|
|
Oct 2021
11:32am, 5 Oct 2021
1,123 posts
|
Big_G
I am the opposite Larkim, so I guess it is different for different people. The optical wrist based monitor on my Fenix is next to useless, except for RHR, where it seems okay. I had the same issue on my older 735XT.
|
Daniels Running Formula. The Definitive Wire.
Jul 2023