# How much harder our body works at high altitude

This is a continuation of my previous post on AMS. Here, I will try to mathematically derive the amount of effort our body should exert at high altitude to keep us going. Please understand that I am not an expert and I have used the information available on internet to make these observations. References are given at the end of this post.

Effective oxygen at sea level is: 20.9%
Barometric pressure at sea level is: 101.325 kPa (760 mmHg)
Effective oxygen at 3962mts is: 12.7%
Barometric pressure at 3962mts is: 64 kPa (478 mmHg)

I calculated with the altitude of 3962mts as Kaza is at altitude of 3800mts and this is where I first got AMS symptoms.

Effort your body must exert to keep you going is inversely proportional to effective oxygen and air pressure.

Thus, effort your body exerts at sea level, E1=1/(20.9*760)
Effort your body exerts at 3962mts, E2=1/(12.7*478)

A quick calculation shows that E2 is 2.6 times higher than E1.

This is assuming that parameters such temperature, humidity and others are all same, which is NOT the case. So these numbers are only to illustrate the effects of altitude and how much harder your body must work at high altitudes.

At any rate, your body is working at least 1.5-2 times harder to keep you going at 3962mts when compared to sea level.

References:
1. Altitude air pressure calculator – http://www.altitude.org/air_pressure.php
2. Oxygen levels at various altitudes – https://www.wildsafe.org/resources/outdoor-safety-101/altitude-safety-101/high-altitude-oxygen-levels/
3. Living in thin air – http://www.altitude.org/why_less_oxygen.php