After my father passed away my family decided to give me his Oximeter which is that small thingy (technical term) that they clip onto the end of your finger at the hospital or doctor's office to measure the percentage of oxygen in your blood. Given that I've struggled with getting enough oxygen at altitude, I've considered buying one before, but held off due to the $300 cost, As a result, it's a sweet and much appreciated gift.
One of my hesitations about buying one was that I wasn't sure how much information out of it. It's easy for me to justify the cost of a GPS as I know what to expect out of it and use one very, very often. Knowing my blood O2 % was either going to be really revealing or really boring.
At sea level it's very boring which is what you want. Normal readings are 90-100% below 90% is hypoxia and a potentially dangerous condition. Hypoxia can make both pilots and mountaineers really stupid sometimes. I live at a glorious 20' elevation so mine is 98-99% and other people around me often have 100% readings.
However when I drive up to nearly 7000' I now know that my oxygen level plummets to the 80's without a lot of help with pressure breathing. I made a video testing this out at Bunny Flat on Mt Shasta:
The fact that I can at least temporarily fix it with pressure breathing is both good and bad news. The problem is that the effects of pressure breathing are highly temporary, so you have to be willing to do it a lot, The other problem is that this explains why I sometimes get sick when I sleep at 12,000' even when taking Diamox (a drug that increases your respiration rate). When I sleep, my respiration level goes down and my oxygen level stays very low for too long. What I don't know yet is if there's a way that I can adapt by spending a night or two at just below the altitude that I get ill.
Even small changes in altitude will affect blood oxygen as there is lower air pressure. Even in Redding (1000') my reading was 96%. In Mt Shasta City (3653') it was in the low 90's.
It probably is the powers that be telling me that I have the wrong hobby and I should be doing more kayaking, sailing, and other sea level events. I love kayaking and know how to sail and live near the water, but there's something about the mountains that calls out to me. It may be that I am doomed not to climb super high (I don't climb well above a certain altitude which varies), but I have a new toy/tool and can gather a fair bit of information with it.
The next thing to do will be to drag my sorry butt up to Horse Camp at 7900' and hang there for a couple of days and see if my base level of blood oxygen changes.
Another thing I want to check on is how is my O2 level affected by exercise. Is my leg dragging because of low oxygen?
This should be fun. Besides it's the climbing season and it's gorgeous even if I'm not getting up super high. I'm also learning to ski off piste and skiing in June is just glorious - note the crowds on Mt Shasta.