Mountain climbers subject themselves to some of the harshest conditions on the planet. It is taxing on the body, especially the respiratory system. The pressure in the atmosphere controls oxygen levels and air density: As altitude increases, air pressure decreases due to lower oxygen content, making breathing more difficult. Adaptation is crucial to climbers because they risk illness and even death if their body does not adjust to the changes.
Oxygen in the Body
Oxygen is critical to survival. It provides energy to the cells but first must pass through lungs. In the lungs, atmospheric pressure forces air into the alveoli, which are little sacs surrounded by filled blood vessels. The greater pressure in the sacs causes the oxygen to enter the blood, specifically red blood cells. In exchange, they take out carbon dioxide. Exhaling completes the body's waste removal process.
Changing Pressure
Breathing changes occur when atmospheric pressure is altered because the oxygen concentration in the air changes. The body needs a certain amount of oxygen in the blood. Sea level air pressure is greatest and contains the most oxygen, making it easier to breath. Pressure decreases with altitude because there are fewer molecules of oxygen. It takes time to get used to these changes. Measurements of blood oxygen levels are important tools for climbers because they show the body's reaction to the new pressure levels.
Altitude Sickness
Maintaining proper blood oxygen levels wards off altitude sickness, which can be debilitating. Signs of this illness include shortness of breath, nausea, dizziness, fatigue and general weakness. It is best to rest if any symptoms arise because they might lead to fainting or worse. If you fail to acclimate, you should descend. Improving acclimatization is achievable through training and measuring the pressure beforehand gives climbers a guide for this training.
Adaptation
The goal of training for a climber is a more efficient circulatory and respiratory system. Exercising and hiking progressively are the way to achieve this. Start your routine at low altitude and slowly increase to give the body time to adjust. A good exercise program will result in better physiologic function; this is the training effect. "Fitness: The Complete Guide" states that "The training effect increases functional capacity of muscles and bodily tissues as a result of increased overload placed on them." In terms of respiratory function, there is higher blood production, leading to more red bloods cells to carry more oxygen.
References
- Outdoor.com: Preparing for High Altitudes
- "Fitness: The Complete Guide"; Frederick C Hatfield PhD; 2008
- PBS.org; NOVA online; Everest How the Body Uses Oxygen
- Kids.earth.nasa.gov: Atmospheric Pressure
