Why do we breathe less well at altitude?

Caution : You must consult your doctor for your health. This page presents only a personal and alternative point of view which should not be considered as an attempt to prescribe medicine.

We breathe less well at altitude!

This is a proven fact, and only high altitude enthusiasts can attest to it.

This phenomenon called hypoxia occurs when there is a mismatch between the oxygen needs felt by the body and the actual intakes.

Hypoxia does not occur at any altitude.

So climbing to the top of a 20-story tower is not enough to suffocate.

Certain atmospheric conditions must be met.

Why do we breathe badly at altitude?

When respiratory failure occurs at altitude, the first parameter indexed is the composition of the air.

However, it should be pointed out, this composition remains invariable in the plains or in the mountains, with a few nuances.

In fact, whether at low or high altitude, the ambient air contains 21% oxygen and 78% nitrogen.

It also contains some additional gases.

This composition remains constant as long as the stratosphere is not exceeded.

In fact, as long as the altitude does not exceed 8,500 meters, the only change that can be noticed is that of the pressure on the earth.

Thus, the higher you go, the more the atmospheric pressure weakens.

This phenomenon has as a corollary the decrease in the concentration of inspired air.

Subsequently, at equal volumes, the air taken from a higher altitude level will have a lower concentration than that of the lower altitude level.

The inhaled oxygen will therefore be less, which will cause respiratory distress.

What are the consequences of altitude hypoxia?

This depletion of oxygen at altitude is not without consequences for the body.

The first of these is the onset of hyperventilation.

Indeed the person, from a certain altitude, will have the feeling of suffocation.

She will try to alleviate this condition by breathing faster to bring more oxygen to the body.

Besides this symptom, altitude hypoxia also causes physiological reactions such as headache, nausea, dizziness, from 2500-3000 meters above sea level.

It has also been found in people living at altitude sleep disorders, including apnea.

Several scientific studies have shown the negative impact of hypoxia on sports activities.

These studies explain this limiting correlation by the weakness of the poorly oxygenated brain.

The latter therefore finds himself disturbed in his ability to order muscle contraction.

Sports activity therefore becomes difficult to perform.

It should also be noted that these consequences are not systematic for everyone.

Indeed, some people have an admirable resistance and can climb up to 4000 meters of altitude without showing the slightest disturbance.

Others, on the other hand, more sensitive, develop symptoms at an altitude of 2,000 meters.

Either way, the organism somehow defends itself as long as you stay in the stratosphere.

In fact, even planes do not allow themselves to fly above 8,500 meters above sea level.

What are the compensatory mechanisms in the event of hypoxia at altitude?

When the body is faced with a situation of oxygen depletion, it puts in place different mechanisms to mitigate the effects and ensure its survival.

The first is hyperventilation.

Although it is presented as a disadvantage of a high altitude climb, it is mainly out of survival instinct that this phenomenon occurs.

It allows large amounts of oxygen to be supplied to the lungs.

Hyperventilation is also accompanied by a marked increase in the amount of blood pumped by the heart.

This reaction follows the same logic, namely: to compensate as much as possible for the oxygen deficit in the organs and tissues of the body.

Besides that, after a certain period of time at altitude, substantial changes can be observed in the body.

This is how the quantity of red blood cells increases, in order to provide an effective response to hypoxia.

By increasing the volume of blood, the body thus ensures that it can transport the maximum amount of oxygen to the various organs.

It should be noted that this physiological reaction is sought after by certain high-level athletes who do not hesitate to stay at high altitudes to increase their blood flow.

This, once descended to low altitude, allows them to offer great performance.

Conclusion

From 2,500 meters above sea level, breathing becomes difficult.

This phenomenon is called hypoxia .

It is justified by respiratory distress due to the dilution of the inspired air.

The higher the altitude, the more symptoms are seen in the body.

The first symptom is hyperventilation.

It is often accompanied by nausea, dizziness and general discomfort.

These inconveniences are regulated quite quickly depending on the health and adaptability of your metabolism.

Note that not everyone reacts the same at high altitudes.

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