High-altitude climbing is not something you want to take lightly.

Guided high-altitude climbs started only a couple of decades ago, although now thousands of adventurers are scrambling up mountains as high as Kilimanjaro and Mount Fuji each year.

Naturally, the number of climbers willing to try summits over the 8,000-metre, like Dhaulagiri, Annapurna Circuit or even Mount Everest is much more limited but still higher than ever before.

Having more climbers ascending these peaks does not make the experience any easier.

Whilst mountaineering gear has greatly advanced and helps less experienced mountaineers ascend, there are no substitutes for physical fitness and mental willpower.

Whilst offering genuinely unforgettable moments, adventurous climbing is a physically demanding activity and requires a high level of stamina, good health and strength.

This article will help you get a clearer of what that means.

In high-altitude climbing our body exerts a lot of energy to walk, grab, pull and breathe in the ever reducing air pressure, which practically means that the air you inhale has considerably less oxygen than the one you are used to.

The higher you go, the less oxygen you draw in, the faster you have to breathe to adequately supply your lungs, the quicker your heart and muscles get tired.

In addition, staying for several hours in such conditions takes its toll in your mental and cognitive capacity, body mass and composition, as well as your immune system.

As a consequence, there is a growing risk of developing acute mountain sickness, which actually is the grave combination of having excess fluid in your lungs and brain tissue, and could, if not treated immediately and properly, pose a threat to your life.

It is essential to know all the possible symptoms (such as a headache, loss of appetite, queasiness, lingering exhaustion, light-headedness, and troubled sleep) and take immediate action by retreating to a lower altitude and getting medical attention.

Exhaustion (both physical and psychological) and mountain sickness are behind most unsuccessful summit climbs.

Of course, there are ways to balance out these issues and obstacles. Proper acclimatisation is the most significant of all.

Good, or even excellent, fitness levels cannot shield your body from complications related to altitude and barometric pressure.

Poor fitness and stamina could make the symptoms harsher and even harder to cope with, but they certainly are not the main cause of these physical changes.

Acclimatisation is the process of adjusting your body to another environment – in our case one of higher altitude, temperature, humidity and barometric pressure – and thus ensure its top possible performance.

Acclimatisation is the best non-pharmaceutical means of minimising the risk of developing altitude sickness.

Acclimatisation requires varied periods of time, depending on the severity of the changed environmental conditions.

The climber must spend a period of time (usually a few days) at relatively moderate altitude (usually from 2,000 to 3,000 metres high).

You must stagger the ascent, by pre-defining the maximum vertical elevation to be covered within a day (typically, somewhere between 300 to 600 metres).

Acclimatisation days should not be confused with rest days; the first aim at helping the body adjust to higher altitude conditions, the latter to allow the body and mind to regain strength and recover from the strenuous effort.

In demanding high altitude climbs, they are both necessary.

In some cases, when climbers make preparations for rather fast ascents, they perform pre-trek acclimatisation sessions days before starting to climb, which involve the same basic practices but in natural or artificial environments with similar conditions, in an effort to expedite their bodies’ adaptation.

Acclimatisation in artificial environments is generally referred to as acclimation and is achieved through:

  • Hypobaric hypoxia – the state of normal oxygen concentration but in lower barometric pressure
  • Normobaric hypoxia – which is exactly the opposite – typical barometric pressure but with less oxygen

Generally, such conditions can be achieved artificially in altitude tents and environmental chambers, enclosures designed to simulate specified environmental conditions.

Proper acclimatisation is crucial but is not enough to get you to the top.

Physical fitness is equally important, and high altitude ascents require well-studied preparation spanning several months and including hours of hiking with loaded packs of 30 to 30 kg for several days, over terrain with characteristics similar to those of the final ascent – but in lower altitudes.

Naturally, the higher the ascent, the more rigorous and longer the preparation.

Mountaineers getting ready for summits over 7,000 metres may start their training as early as a year in advance, integrating into their training sessions hiking and climbing of ever-increasing difficulty.

Such training programmes, aside from strengthening the body and giving an idea of the difficulties waiting ahead.

They also bring out the climber’s physical weaknesses and give him/her the chance to work and improve them, particularly regarding stamina and muscle mass, strength and elasticity.

On the other hand, trek training is just part of the whole preparation. Personal training is also important, especially aerobic exercise, like running or swimming, and mild weight lifting.

The climber must also adopt a balanced diet, customised to provide the body over a period of several months with the mass, fat and nutrients necessary to sustain the rigours of the ascent.

Body mass and fat are of exceptional significance in higher altitudes, for metabolism works in different rates in thinner air.

The web is full of interesting and highly informative articles regarding preparation techniques for high-altitude climbs, but do not fool yourself; there is no DIY when it comes to high-altitude climbing.

Asking for professional counsel and training from seasoned mountaineers is a critical part of every high-altitude climb, especially regarding your state of physical fitness.

Trek sessions with climbers experienced at higher altitudes can provide valuable insights, and an evaluation of your stamina and physical strength. Likewise the honest understanding of the undertaking and the risks involved.

Acknowledging your weaknesses is essential when preparing for the physical and psychological challenges inherent to any high-altitude ascent, and giving the best chance of a successful and safe climb.

author's profile

Charlotte Johnston

Charlotte walks anywhere and everywhere she can. Although she hasn’t ticked off as many official routes as she’d like, she has walked her way around large parts of Latin America, Southeast Asia, New Zealand and the Pacific Islands.

Favourite routes include the Inca Trail, Acatenango in Guatemala, Mount Batur in Bali, the UK’s Three Peaks and all parts of the stunning Lake District

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