On the way up Pole Mountain
High altitude. Far above the level of the sea. Here, we consider our breath. Such a simple thing. We do not take breathing for granted. Each breath can be a struggle, a blessing. Yet we adjust.
They say it takes four days. And our bodies actually adjust. Remarkable. We don’t think about it, work at it, try for it; it just happens. Four days. What happens after four months? Four years? More?
High altitude. It is often defined as beginning at an elevation of 8,000 feet. We live at an elevation of nearly 10,000 feet. We ascend higher regularly. Tree line here is at 12,000 feet. The highest peaks in this area are just under 14,000 feet, and in the state, just over.
High altitude. Breathe. You can feel it. The changes are real. We may say there is less air up here. That is how it feels. Yet there is about the same amount of oxygen as there is at sea level. The problem lies in the pressure.
Atmospheric pressure (which is measured with a barometer and is also known as barometric pressure) is a measurement of air’s force against a surface. At low elevations, the pressure is greater, since the molecules of air are compressed from the weight of the air above them. However, at higher elevations, there’s less pressure from above, and the air molecules are more dispersed.
The percentage of oxygen in the air at sea level is about the same at high altitudes, roughly 21 percent. But because of the decrease in barometric pressure, as mentioned above, the oxygen molecules are more dispersed. This is what we call the thinning of the air. In a given volume of air, say one breath, fewer molecules of everything are present, including oxygen.
They higher you are, the lower the pressure. As the atmospheric pressure drops, the quantity of oxygen, CO2 and water in each lungful of air decreases proportionally.
Breathe. At 10,000 feet, the atmospheric pressure falls to less than three quarters of that at sea level. Breathe deeper. With each breath, you receive only 70% of the oxygen available at sea level.
Breathe. At 12,000 feet, with each breath, you receive 40 percent less oxygen than at sea level. Breathe deeper still…
It is real. The air is thinner.
Your body will feel it. There is less oxygen with each breath. 30% less with each breath here at 10,000 feet. Less oxygen in your breath means less oxygen in your blood. 10% less oxygen in your blood here at 10.000 feet. You body will need to adjust. And amazingly, it does.
We begin by breathing harder. In the altitude, you breathe faster and more deeply to maximize the amount of oxygen that can get into the blood from the lungs. Yes, you hyperventilate. Your heart pumps more blood to increase the supply of oxygen to your brain and muscles.
Now head on up to 12,000 feet, our tree line. Then continue further up.
The amount of oxygen required for activity in our bodies does not change. Our bodies must adjust to having less oxygen. We begin with breathing faster and more deeply. The extra ventilation increases the oxygen content in the blood, but not to sea level concentrations. Pulse rate increases. Our hearts pump harder to get more oxygen to the cells.
We adjust. We acclimatize.
Within four days, our bodies can adjust. The depth of our respiration increases. The pressure in our pulmonary arteries is increased, forcing blood into portions of our lungs which are not normally used during sea level breathing. Our body produces more red blood cells to carry oxygen. More red blood cells and capillaries are produced to carry more oxygen. Our body even produces more of a particular enzyme that facilitates the release of oxygen from hemoglobin to the body tissues. The lungs may actually increase in size to facilitate the osmosis of oxygen and carbon dioxide. There is also an increase in the vascular network of muscles which enhances the transfer of gases.
I find it quite remarkable that we can adjust. Change. Alter to the alititude.
And every time we descend then rise again, we must acclimate again. The changes to our body may not be permanent.
And sometimes, we must descend.
The higher we ascend, the greater our risks. The risks are as real as the thinning of the air.
Here, we adjust. We learn to drink more, eat more, sleep more, slow down, do less. Our bodies work harder just being.
I wonder about the long term effects of altitude. What happens to those that live here? That ascend regularly? That rarely descend? No one has remained here as long as we have before. Perhaps no one will again. What will happen when we leave?
The air will remain the same. The mountain will remain the same. Our bodies will adjust. The effects of the mountain on me will last even less than the effects of me on the mountain.
How foolish we would be to think we are enduring, essential. We are no more than a drop of water in the mighty river. But each of us clings to our own importance and permanence as desperately as we grasp for a deeper breath with each step we take higher.
We are adaptable creatures. We learn to breathe.
On the way back down Pole Mountain