Smart Hiking (3) ~ How to recognize "sign"

Difference between casual hiking in high elevation and Himalaya expedition?

One thing I can tell is that there is some difference between a casual hiking in high elevation, which is somewhere around 9,000 ~ 15,000 feet and mountains in Himalaya.
A major factor is "duration".   In general, those expeditions can be long enough to acclimatize the altitude up to some elevation.   However most of casual hiking could be done within a few days.   I think it is probably not long enough to acclimatize the elevation.   This means some symptoms for high altitude sickness is probably given and I think the key is probably to minimize the impact of the elevation.  That is a big difference.

On the other hand, most of strategy people believe is a similar way as those expeditions.  Something like staying higher altitude in a previous night....   However, I personally do not believe it helps a lot.  Based on my experience, I did not really realized that I was getting some symptoms until I really have obvious symptoms.  I think that is difficulty of such hiking.

Need some clear factor to quantify the impact to human body

Especially in early stage or the elevation is probably not high enough to see very clear symptom of high altitude sickness, most of people think "I am good".  Then people tend to walk a regular pace as lower elevation based on their experience.   People who has a lot of experience in that elevation, they might have a better idea how they can manage the pace with the elevation.  In this case, it is probably less problem.  The problem is many people do not have a lot of experience above 10,000 feet.   Therefore, they might walk over pace and exhausted.

If people can have a good factor to recognize the impact, it might help to adjust the pace.

One of popular factor for high altitude hiking / climbing is probably SPO2 (Peripheral Oxygen Saturation).   The value can be measured by pulse oximeter and many expedition might use it as a reference for altitude acclimatization.   If people measure SPO2 in lower elevation like lower than 1000 feet, then the value is typically more than 95%.  However if people is getting higher elevation, this value is getting lower.  Based on my experience, SPO2 valur in 14,000 feet was sometimes less than 80% which is really low value.   It is probably a good factor to show some impact to human body in higher elevation.  This value could be lower once people acclimatize the elevation and it is a good factor for acclimatization.   It is probably very useful for the expeditions.  But it is probably a little hard to use for hiking in a short period.

Another one is probably heart rate.  I am also runner and using a running device (watch) with GPS to track all race and training data.  Many devices nowadays can capture heart rate during the activities.  I also collect heart rate data during hiking to Mt. Whitney which is more than 14,000 feet.  I realize that the heart rate is getting higher if I am in higher altitude even waling pace is slower.
Also, heart rate is one of very good factor to manage the strength of a training and manage running pace in running world.   Therefore, I believe a similar idea can be applied to hiking.   That is the idea to manage walking pace in higher altitude during hiking.

I will show some examples which indicates some impact of higher elevation.

(To be continue)