trekking in PeruBlog

Aiming High - How to Avoid Altitude Sickness

Our guest blogger today is Huw Miles, a freelance Expedition leader, river guide and outdoors instructor. Here, he gives a run-down of the best ways to avoid altitude sickness if you are planning on climbing big peaks or trekking at above 3,000 metres.

1. Train. Although being fit isn't necessarily a guarantee you'll cope well with altitude, having an effective cardiovascular system is advantageous. Going out and walking for hours is good idea to get your feet used to the rigours of pounding a trail for hours at a time. However, running or cycling is better preparation. Your heart will go like the clappers at altitude, so you'll benefit best by doing the same during training. Get your heart rate right up, get out of breath, and get sweaty!

2. Acclimatisation. Choose a route that has built in acclimatisation days or rest days. Your body makes a series of adjustments to become better suited to life in thin air. If you climb too high too fast your body will struggle to keep up with the changes in environment and you will suffer. A good way to monitor your aclimatisation is with a SATS machine which measures the level of O2 saturation in your blood. The longer you can spend getting used to altitude the better.

3. Take your time. Slow your pace down. You will climb more efficiently if you can walk at a steady pace for hours, without stopping, rather than racing along as if you're being chased only to stop every five minutes for a rest. It's back to the Tortoise and Hare fable. "Pole Pole" as they say in Tanzania.

4. Climb high, sleep low. A well planned itinerary should involve climbing higher on the mountain than you intend to sleep. By climbing high, you are pushing your body hard and forcing it to adjust to working with very little oxygen, but then by descending, you allow your body to recover and rest effectively, in a less hostile environment. It's an old adage that has shaped the way we climb, yo yo style, for decades.

5. Hydrate. At altitude, there are plenty of things out of your control: loss of appetite, nausea and head aches, for example. Your hydration, however, is well within your control and should be carefully monitored. You should be passing urine the colour of champagne, not apple juice (although if your pee starts to fizz, like champagne, you've got something seriously wrong!) Hydration is particularly important if you are taking diamox ,which works by flushing bicarbonate out of your liver. This means increased urination so it is important to replace lost fluids. A good tip for this, if you struggle to drink alot of water, is to take some squash up with you. You are much more likely to drink if it tastes good, than if it's boring old H2O. This is also a good way of keeping blood sugars up. Sip little and often and resist the temptation to guzzle as your body will not absorb fluids effectively like this. On Kili it is recommend to take on 4-6 litres a day. This can come in the form of porridge, soup, plenty of fruit and hot drinks; leaving you with less to chug through as you walk.

6. Choose what you eat. "Sneaking" fluids into you by eating foods with with a high water content is a good idea but it is also important to think about what other fuels you are giving your body. Often people start to loose their appetite at altitude, so if you can't manage to eat much, make sure you are, at least, eating the right stuff. Carbs are your friend (forget the Atkins Diet for now). You will be literally burning calories in your sleep at altitude, so slow releasing energy from bread, pasta, rice etc is brilliant. Proteins are also important for growth and repair of weary muscles so keep these up if you can.

7. Sleep when you can. Sleep deprivation can effect everything. I have never seen a client end their trip prematurely when lack of sleep hasn't been a factor. To combat this there are a few things you can do. Go camping during your training to make sure that the first time you camp at altitude isn't also the first time you've slept under canvas. Try and get used to sleeping in a sleeping bag and train yourself to sleep on your back in the weeks approaching your departure. Ear plugs are a great idea. It may be true that, " space, no one can hear you scream" but in camp everyone can hear you snore. If you are tired when you first get into camp, sleep. You might find it difficult later so don't pass up the opportunity to grab some shut eye. If you need to pee in the night, just get up and go, don't hold it in hoping to drop off. Finally, if you can't sleep, try not to worry. Do your best to relax and empty your mind, your body and mind will at least be resting and they say eight hours rest is as good as six hours sleep.

8. Diamox. This is often a strangely contentious issue. People have a preconception of Diamox being "cheating", masking symptoms or having side effects worse than altitude sickness. Let me dispel a few myths. Firstly, if you have spent months planning and preparing (and doubtlessly saving) for you expedition, you will want to achieve your goal. Diamox isn't a guarantee of topping out, but it does give you the best chance possible. It isn't a super drug that will make you immune to the rigours of life at altitude, I promise there will still be plenty of challenges to be faced. So please don't view it as "cheating". Secondly, Diamox doesn't treat the symptoms of altitude sickness (such as headaches or nausea), it targets the cause (hypoxia- lack of O2 in the blood) and helps your body acclimatise better. So there is no question of it masking symptoms. Lastly, the side effects are: slight pins and needles in the extremities; and increased urination. Among the list of ailments Diamox can help prevent are: acute mountain sickness (AMS) and high altitude cerebral and pulmonary oedemas (HACE and HAPE). It is of course a personal decision and you should discuss it with your GP before deciding the best course of action. Perhaps take it a day or two before leaving the country to see if you have any reaction to it.

9. Top is half way. Most accidents on mountains happen on the way down. People are physically and emotionally tired and no longer have that drive to reach a target. For many, getting to the top is their target. Ask any guide in the world and they will tell you getting to the bottom is their goal. Getting to the top is optional, getting to the bottom is compulsory. It helps mental preparation if you have clearly in your mind from the beginning that your journey does not stop at the top, you still have to get down. The mind and body have a very close relationship and I have seen time and time again people's body's starting to give up when their mind thinks they have achieved their objective. It still happens to me every time I finish a trip! The right mental attitude is key.

10. PMA. Positive Mental Attitude. Corny as it sounds, a good positive mental approach is one of the most important things to pack in your bag - never leave home without it. Mental toughness is vital to overcome whatever the mountain throws at you. If you can keep laughing in the face of adversity or see liquid sunshine where others see rain, you far less likely to be overwhelmed by all the obstacles in your way. It is also hugely important to team moral. Unless you're on a solo journey, you will need a good team around you. They will keep you going when your head drops and it's your job to pick them up when they are on their chin straps. Attitude is infectious, be aware of what you are spreading!

Huw Miles works as an adventure consultant designing, risk assessing and leading expeditions and events in the great outdoors for corporate groups, charity clients, stag and hens or individuals. For more information – visit his Miles Away website: