[LandR]

I always thought resting heart rate while sleeping was a pointless metric ?

YOu can have a resting heart rate while sleeping in the 30s, yet your real resting heart rate in the 60s.

I don't need a watch to tell me if I was sleeping or not, I was there, I know if I was sleeping... I also don't see the point if it telling me if I got enough sleep or not. Again, I know if I didn't get enough sleep as I'm tired...

I also don't think it's sleep tracker is accurate, I've had my garmin tell me I have taken naps when I hadn't. I was just lying on the sofa watching a film and didn't get up for an hour or so. That doesn't mean I'm asleep.

[Lio]

I find sleep tracking to be really useful.

One thing that surprised me has been seeing the affects of either alcohol or caffeine on the type and quality of the sleep I get.

Even if the absolute numbers aren't 100% accurate the watch definitely spots when I've had even 1 beer during the evening.

I also find heart rate variability interesting. I can't put much spin on the absolute numbers but after either heavy exercise or if I've been unwell I can see the variability rate really drop.

[kadoban]

Sleeping heart rate is useful because it gives you a good "resting" value. Resting heart rate will tell you if you're getting sick, before you have any real symptoms.

[doix]

Yeah, I first learned that from the "HOW TO SKATE A 10K" ebook[0] that was posted here[1] a while ago. He talks about how he tracked heart rate to figure out when he was going to get sick.

I then started looking back at my historical garmin data, pretty much everytime I was sick, my HRV would drop a few days before. I then started monitoring my HRV closer and taking it easy whenever it dropped. Anecdotal data from one person here, but I found that I get sick less and when I do get sick, it's usually not as bad.

[0] https://www.howtoskate.se/

[1] https://news.ycombinator.com/item?id=30320639

[kadoban]

Yeah HRV is especially good for that. Mine doesn't really expose HRV very well, I'm guessing because I'm a couple of generations back, so I have to make due. Works pretty well even so though.

[The_Colonel]

You remember when you fell asleep? I don't. Watch tracks how often you wake up, how long you spend in the deep sleep, etc.

A lot of value is in the long term trends. One bad night doesn't mean much but if our sleep quality is trending down over weeks, it's a sign you should change something.

[iamacyborg]

> You remember when you fell asleep? I don't. Watch tracks how often you wake up, how long you spend in the deep sleep, etc.

Anecdotally, this is very inaccurate for me.

[LandR]

Yeah, plenty times I've got up during the night multiple times, sometimes out of bed entirely wand walking about and the watch hasn't realised this at all.

Similarly I've been in bed, awake, reading, unable to sleep and the watch has thought I was sleeping.

[LandR]

If I'm watching a film, yes... I know if I've fallen asleep and missed half of it!

[jerlam]

> real resting heart rate in the 60s

What makes one measurement "real" and the other one "not real", if you're mainly using it as a personal metric?

The reason that the traditional definition of resting heart rate exists is people didn't have 24/7 heart rate monitors, and doctors had to measure what they are able to measure. And they still can't measure it well, because patients often have white coat syndrome and there's not enough time during an appointment for people to relax fully.

The Apple Watch, which uses the traditional definition, has to use algorithms to guess which of its measurements counts as "resting" or not, which adds complexity. In contrast, lowest HR during sleep is a more reliable and consistent measurement.

[LandR]

What I mean is, you can be pretty unfit and still have a resting heart rate in the mid 30s when you are asleep. The same unfit person takes a resting heart rate just sitting in a chair doing nothing for a minute or two and it's probably not going to be anywhere near 30.

I've known people who have had resting hearts in the low 40s, but actual resting heart rate when awake is closer to 70!

I think Garmin uses resting heart rate when you are asleep as it makes it seem like you have a really low resting heart rate, where you might not. I think it's overly flattering.

[nradov]

Citation needed. I'm not aware of anyone who is unfit and has a sleeping heart rate in the mid 30s. Let's see some hard data on that.

Garmin watches calculate resting heart rate as the lowest 30 minute average.

https://support.garmin.com/en-US/?faq=F8YKCB4CJd5PG0DR9ICV3A

[jerlam]

I think we're talking about two different things.

You're saying that some devices are measuring "resting heart rate" when it's not using the traditional definition, and comparing that number to the traditional definition is wrong, and I would agree.

I'm saying that the traditional measurement of resting heart rate is bad for a variety of reasons, one of which is that taking it while sitting at your couch at home after 15 minutes and having a stranger take it in the weird doctor's office can have very different results. And if our smart devices consistently measure an RHR on a regular basis, that's probably a better measurement of progress.

[KeplerBoy]

I guess most metrics are pointless if looked at in absolute terms and isolation, but trends might still be interesting.