Let me in on the secret. How to reliably get Pulse Ox?

K2 over 4 years ago

I don't pretend to know how most of the watch's inner functions work. But Pulse Ox is the blackest of black magics. How the hell do you get a reading? I'm not talking about whether it's accurate or if it lines up with "medical grade" devices. I just mean how to get a reading to complete, and how long it takes.

I usually take spot checks from the widget, and it seems completely random how the process will pan out. Sometimes, it says "measuring" and within 3-4 seconds presents a result, so fast it never cycles to "keep still." Other times, it will spin for 10+ seconds, alternating between these two messages. And other times, after half a minute of trying, it'll give up completely.

I always come away thinking there's something I did (or can do) that can influence the speed/success of getting a Pulse Ox reading, but it never pans out next time I try. I've thought that maybe it's too bright, or too dark. The watch band is on too tight, or too loose. I have to hold the watch against my skin, or let it sit naturally. That the Elevate sensor surface should be wet, or dry, or sweaty, or clean. Or it should be higher on my arm, or lower. Or sitting against the wrist bone, or far from it. Or over a visible vein, or a clear patch. I've never found anything that is a reliable predictor of whether a reading will complete. About the only thing that seems consistent is if a reading doesn't finish the first time, it's unlikely to finish no matter what I do, and I should just give up and try again later.

No, it's not important. But it's kinda driving me nuts, because it really seems like a roll of the dice :)

0 imcluelesstoday over 4 years ago

Agreed! This is my biggest gripe with the fenix. It's so hard to get a reading.

0 C.sco over 4 years ago

The secret is, use it in continuous mode when you significantly go up in elevation, to track your SPO2 trend over time to see how you're acclimating.

That's the only intended use for pulseOX, and it works great for that. For any other use case, get a medical-grade pulse oximeter.

0 Geroelltrampel over 4 years ago

Many of Garmins readings seem like a roll of the dice :-)
For watching your acclimation I rather would recommend a 25 bucks pulox from Amazon. It's very fast and provides quite accurate readings.
I never got reliable readings from the Garmin Puls Ox, but it depends on your ambition. The less demands, the more satisfied you will be ;-)

0 Former Member over 4 years ago in reply to Geroelltrampel

Geroelltrampel said:
it depends on your ambition. The less demands, the more satisfied you will be ;-)

Or you can use the feature as intended as C.sco stated. Why does a sports watch have a PulseOx sensor? We'll let John Hopkins Medicine answer that:

Athletes or people spending time at altitude will want to monitor blood oxygen levels.

If you're not spending time at altitude, then there's no need to utilize the feature.

0 Dr Phil over 4 years ago

K2 said:
I just mean how to get a reading to complete, and how long it takes.

This is where it is important that there is plenty of flesh under the sensor. If I want to be sure of getting a good Pulse Ox reading I'll move the watch even further away from my wrist bone. I then make sure the watch is tight and that I keep still for the time needed to get the reading. it does help to be warm too.

0 Geroelltrampel over 4 years ago in reply to Former Member

There was no need to answer a question that has not been asked.

Its not about the usecase but the reliability has been questioned. Therefore I recommended a cheap device that can do much more reliable readings than Garmins PulsOx sensor on their watches.

0 Former Member over 4 years ago in reply to Geroelltrampel

Geroelltrampel said:
For watching your acclimation I rather would recommend a 25 bucks pulox from Amazon

Geroelltrampel said:
Its not about the usecase but the reliability has been questioned.

But if you're not using it for how it's intended, how can you question the reliability?

0 acousticbiker over 4 years ago in reply to C.sco

The use case that has significant value is to potentially detect desaturations while sleeping which would indicate sleep apnea but the F6 sensor isn’t accurate enough to rely on that.

Otherwise, not much value, including for altitude, as pulse ox readings are not factored into the firstbeat altitude acclimation algorithm, which just goes by number of days at a particular altitude (see DCR’s F6 review for more detail).

0 K2 over 4 years ago in reply to Dr Phil

That's definitely one of the things I've tried as well, farther up the arm, away from the wrist bone, band tight. Sometimes I get a reading in 5 seconds, sometimes nothing after 30 seconds. Same as every other variable I've tried

Look guys, I get the use case argument, and I'm on board. I've disabled Pulse Ox generally; not on 24/7, not during sleep either. Since I'm not traveling to altitude, nor suffering from sleep apnea, there's little current value for me, especially if it doesn't figure into any tracked health/performance metrics. Why take the significant battery hit?

But I still want to know how it works. If there's a "best practice" to get an accurate reading (or any reading at all), wouldn't that be good to know for when you DO eventually use it according to Garmin's intent?

0 Dr Phil over 4 years ago in reply to acousticbiker

acousticbiker said:
The use case that has significant value is to potentially detect desaturations while sleeping which would indicate sleep apnea but the F6 sensor isn’t accurate enough to rely on that.

Neither is it intended to be used for any medical diagnosis.