If you’re new to altitude diving, you may be wondering why there’s such a focus on acclimatization prior to diving. There are several factors that play roles in scuba diving safely at high altitudes, and many of them have to do with human physiology. How does thinner air at higher altitude affect your body? Knowing the answers will give you a greater understanding of acclimatization.
Living in An Ocean of Air
Our planet is surrounded by what essentially amounts to a vast ocean of air – one that’s several miles deep. The atmosphere exerts about the same amount of pressure on our bodies as approximately ten meters of seawater when we are at sea level, and it has a similar effect on the air at lower altitudes. At sea level, air is denser; as you gain elevation, the air is less compressed by atmospheric molecules above and is thinner.
The most important effect of this decrease lies in the number of air molecules available to the body. At lower pressure, in thinner mountain air, there are fewer molecules in any given amount of air. Despite this, oxygen content remains at 21 percent. Even so, because there are fewer molecules, there’s less oxygen to breathe – and less for your body to use – at high altitude.
Physical Changes and Acclimatization
Our bodies are amazing in many ways. One of the most incredible functions is the ability to make physical changes during the acclimatization process. During acclimatization, two things happen quickly:
- You find yourself breathing faster and deeper
- Your heart begins to work harder
These changes happen to ensure that your body takes in as much oxygen possible, and makes the best possible use of the oxygen available. Breathing faster and deeper increases the amount of oxygen the lungs transfer to the bloodstream, and your heart’s increased workload ensures that your brain and muscles get the oxygen they need to keep on functioning.
If you begin to feel breathless while at altitude, it is a sign that your lungs are having difficulty supplying the rest of the body with the oxygen required for proper functioning. It’s normal to feel a little out of breath while exercising at high altitude shortly after arrival, but breathlessness while at rest is an indicator that your body is having a very hard time with acclimatization, and it is an indicator that altitude sickness may be developing.
The variation in air density that is responsible for feelings of breathlessness is also responsible for the reduced atmospheric pressure that affects your body as you ascend during a dive in a mountain lake. As a result, it is absolutely vital that you compensate appropriately, as the risk of decompression sickness is much higher at altitude than at sea level, particularly if you haven’t been in the mountains long.
Don’t be afraid to try altitude diving – but at the same time, ensure that you take appropriate precautions. Diving at altitude is less forgiving if mistakes happen, and even the trip to a hospital for a minor case of DCS can put you at higher risk for worse conditions. Protect yourself by allowing for proper acclimatization, and enjoy the many underwater wonders the world’s mountain lakes have to offer.