Pulse Oximetry During Sport

Seconded. I couldn't find much information about the Garmin pulse oximetry, so I bought the device hoping it sufficed for this need, but am somewhat disappointed that it doesn't.

Two settings basically: all day on/off or during sleep. Can't see too much value as a metric during activity. What are you hoping to achieve having it on specifically during any activity?  

Unless you live at or are training at altitude, I can't see too much use for it. Mine is off for that reason.

"As the primary function of this devise is to monitor oxygen levels in the body, athletes may choose to utilize this as a tool during strenuous workouts. Endurance, speed, and efficiency are all important goals to any athlete, and maintaining an effective oxygen range can drastically improve one’s overall performance and help develop these components. Using a pulse oximeter to monitor your oxygen levels while working out can help you make adjustments so that you are getting more equalized oxygen flow throughout your workout session." (Source https://ihealthlabs.com/pulse-oximeter-important-high-endurance-athletes/)

Just thought I'd throw this in as typical of some of the misinformation you can find on the interweb about pulse oximetry measurement. Short of breathing supplemental oxygen there is no way for you to "make adjustments so that you are getting more equalised oxygen flow throughout your workout session." What does that even mean? If you do not have any respiratory issues then you are dependant on the amount of oxygen in the air (that will vary depending on altitude) and your ability to process that oxygen and use it for energy (and that's dependant on your aerobic capacity). 

Yes it is much more complex than that. Again I'd be intrigued to understand how you intend to use pulse oximetry for training.

Agreed, PulseOX is one of the more useless features unless you know your specific need. Even then, it is more or less useless during an activity for most, but I can think of 2 use cases:

* if mountaineering at high altitudes requiring sporadic use of oxygen. But then a quick switch to the SpO2 widget is all you need

* pilots flying unpressurized aircraft. Usually we set a fixed altitude limit requiring constant use of oxygen, but oxygen saturation varies with many factors, hence monitoring levels with an associated alert is something that can be useful and potentially save a life or two. I thought the D2 deltaX and MARQ aviator do this, but it appears they don't

Of course there is the issue of accuracy during movement, so I basically just turn it off and consider it a marketing gimmick

I think the one area you didn’t consider is use while sleeping. With obstructive sleep apnea, the O2 saturation can drop significantly and a Garmin watch could possibly help make this diagnosis which would be extremely important to know. 

If pulse oxymeter was reliable, which is not the case.

I think PilseOx only works when still anyway, so it won't measure anything while exercising.

Agreed!  Once checked your sleep for a few weeks and you know you're all good might as well turn it off and gain 10 days non active battery or 7-8 active days.

I have a friend that found out they had complex sleep apnea while sleeping due to wearing their Garmin.  Three sleep labs layer and they were using a CPAP with good results.   It is a nice feature on a wearable for sure.