UKC

Hi.
I'm sure it has been asked before but:
I'm heading to Nepal for a couple of weeks at Easter and want to try to avoid spending too much time out there acclimatizing before heading to higher altitudes (ie 5000m).
Is there anything that people have done before their trip to speed things up that actually works?

e.g. foods?
Sleeping on top of Snowdon?!

Thanks

In reply to Theho:

We've nothing high enough for acclimatising but spend the time getting as fit as you can.

In reply to Theho:

Before I go back to the UK I like to acclimatise by taking a long cold shower with the fan on and then spending the day in wet shoes before supping a welcome imported bitter. Almost like being there

In reply to Theho:
I've said it before, but there will be naysayers to my technique.
I've never been to the greater ranges, but when training for the alps I used this method.
Every weekend to the Lakes or Snowdonia. Carry a heavy pack and walk as quick as you can.
Climb the higher crags such as Pillar Rock, then descend to a campsite by a pub. Drink too much. Return to the high crag the next day with a hangover that quickly wears off, pushing as hard as possible and rehydrating on route .
I managed to ascend Mt Blanc with no problem, with only an overnight stay in the Cosmiques Hut, the Cosmiques Arête, and a night in the valley.
Worth a go?

In reply to Theho:

https://www.altitudecentre.com/rent/ihe-systems/

Try them, when I've been planing some training they guys all ways seam to have the gear to help me!

In reply to Dave the Rave:


Chance. You could have equally easily been staggering around like a drunk at fairly modest altitude, and a complete liability.


No. Pure luck on your part.

The mountain walking can certainly work for fitness, but acclimitisation is quite different to fitness. That is only built up by biochemical and cellular changes in the body, which take altitude exposure and time. Sometimes, some people are lucky and are not hit even when going pretty high (i.e. Mont Blanc summit or thereabouts), pretty fast. Most often the effects of trying to do this are not pretty at all.

In reply to Simon4:

Diamox at 3500m, just worked for me, Im not a medic though!

In reply to Theho:
Yawn. Told you . Someone from Landan knows better
But at least you will be used to motivating and moving yourself when feeling rotten, even if it's only to get yourself off the hill not up it.

In reply to Simon4:


Yes, and fitness can lead the ill advised or inexperienced to gain height too fast before symptoms of altitude sickness have time to kick in with unpleasant and dangerous consequences. Yes, be as fit as possible but remember it is no substitute for proper acclimatisation.

In reply to Theho:

I've heard that beetroot juice can help, as weirdly, can smoking!

In reply to broken spectre:


Exactly. Not sure about the beetroot, but it would help you leave red patches in the snow for rescue.
I smoked mainly Hamlet prior to the Alps. This lowered my oxygen carrying potential, and got me used to being short of breath. I just cracked on though.

In reply to Theho:

Surely sleeping on Snowdon for a few nights prior to flying would be better than sleeping at sea level? I'm sure it would have an effect just not certain how much, it certainly won't leave you worse off..

In reply to maxsmith:


No.

Firstly, it's not high enough to force any adaptation process in your body. That height would only affect your physiological performance at the uppermost level, such as slightly reducing sprint times etc.

Secondly, even if it did have the most minuscule physiological affect, by the time you got down, got to Heathrow, spent 15hrs flying, 48hrs in Kathmandu, a day travelling to the mountains etc - you would have lost that (virtually non-existent) benefit.

In reply to Dave the Rave:

Well of course I have never done any Alpine or Himalayan climbing, coming from London and all, so what would I know?

To my certain knowledge, nor has Robert.

In reply to Theho:

one of the outdoor shops in Manchester has a decompression chamber
There must be others elsewhere in the country
dont know how much they help!

In reply to wheelo:


Diamox can indeed have some benefit, though it is a bit of a dodgy way of going about things (not morally, practically, it it does NOT work, you are back to square 1).

Actually I found the greatest benefit of diamox was that it seemed to allow you to get better sleep at altitude.

In reply to Dave the Rave:

Your suggestion is actually quite dangerous somewhere like the Cosmiques where quick descent may not be possible. Read a bit about altitude effects. You were lucky. (I am not from London)

In reply to Dave the Rave: your 19.59 post sounds like a suggestion to me.

In reply to Simon4:


I have used diamox routinely in the Alps, but only when I have been certain, through experience, that I would have been ok without it - just to reduce mild symptoms and make acclimatisation pleasanter (I am a very poor acclimatiser). It might have been placebo, but it seemed to work!

In reply to Theho:

Why the rush? Time acclimatizating is necessary, rush and you will have an unpleasant time (walking up mountains with a headache, vomiting, and wanting to go to sleep is not fun!). AMS does not have to kill you to spoil your trip!

Only possible way to acclimatise would be to breathe low oxygen air for many hours per day before. Don't believe the nonsense from the 'altitude gyms' - exercise for a couple of hours at a time in low pO2 atmosphere will do nothing for you.
The Altitude Centre linked to by John_MX is similar but even they don't have any evidence that their technique will help you to pre-acclimatise - their research (at a cursory glance) seems to only supports better performance at sea level following that type of training (although it is quite interesting from a different perspective!)

If you were thinking of using one of these, you ought to spend the money on an extra day of ascending more slowly!

The evidence is that fitness probably doesn't affect how you acclimatise, but higher levels of exertion (from being unfit) will increase the risk of AMS so I think that being fit probably does help.

Diamox is a highly controversial area. It is well proven to decrease your risk of AMS, and if you get AMS will reduce your symptoms. The problem is that if you get AMS and are already on diamox - what treatment can you do except descend?

In reply to Dave the Rave:


That's the spirit that made this nation great. I salute you sir.

In reply to DaveHK:


Shame the national cricket team have failed to honour it, training well, playing effectively and actually WINNING!

Are they British or what? Disgraceful.

In reply to Damo:

Hi Damo, despite beginning your post by saying 'no' you seem to agree with me that sleeping on top of Snowdon would provide a "physiological effect" you wouldn't get at sea level. Although I definitely take your point that you would lose such a miniscule gain while travelling to Nepal!

Does acclimatization work on a sliding scale i.e. the higher you are the more your body adapts, or is there a specific height you have to reach before adaptation begins?

In reply to Theho:


You're right, this has been discussed before on UKC. I suggest to you that if you climb/ walk at 5000 metres without acclimatization you are risking having a bad time because of the altitude.

I can't think of anything you can do in the UK to help before leaving [and certainly not "foods" or "Sleeping on top of Snowdon"]. What you need to do is spend time in Nepal acclimatizing - and not rush this stage.

PS I've spent plenty of time at altitude.

In reply to maxsmith:

I think it is a very complex progression, also the effect on any given trip is very individual specific. But it is probably a logarithmic scale rather sliding, there is a certain point beyond which you are just surviving well enough to function, you will never be comfortable. That is normally at Himalayan altitudes, on the great peaks, there is a level beyond which you are only deteriorating and can only hope to get something done before you are either forced to descend or die (i.e. the well known "death zone"). In the Alps, most people could reasonably hope with suitable preparation (time, height, fitness), to feel perfectly comfortable at height, feeling almost as good as they would be at the top of Snowdon.

The changes also take place over a scale of days to months, obvious ones like increasing red blood cell count are relatively quick but more subtle ones can take much longer. There can also be substantial downsides to even the beneficial changes, most obviously increased red blood cell count increases the risk of stroke and blood clots.

Quite a lot of academic research on the subject, but still remains fairly mysterious.

Most people know about the impact of HAPE and HACE, which can of course be sudden and catastrophic, as against AMS which despite its name "acute" is pretty unpleasant but not really that serious. Well worth thinking in terms of initial routes of ones where you can stop and just descend if altitude or anything else gets too bad, rather than committing routes that have to be completed once you are beyond a certain point.

In reply to splat2million:


I'd always understood that most of the symptoms of AMS are caused by the lowered atmospheric pressure rather than lack of oxygen (which just makes everything hard work). Is this true or am I mistaken?

To the OP: For some people, a trip of only two weeks during which you hope to get to 5000m will consist of nothing but the slog of acclimatisation with no time to actually enjoy being there!

In reply to Theho:

The danger, especially on a short trip, is the temptation to rush. Don't underestimate the benefit of rest days, and if possible use them to go higher but return to sleep at a lower altitude. Also don't try to gain too much height in a single day. If your trip has been well-planned it will have allowed time to take account of both of these requirements, and you should acclimatise and get to 5000m reasonably comfortably. If you rush at it, you may be fine but more likely you won't and you'll put your trip in jeopardy, and possibly your life. Always remember AMS can kill, and at lower altitudes than 5000m.

Stay off the beer, at least until you're on your way back down.

Forget about sleeping on top of Snowdon. The air pressure in the aircraft cabin on your flight is equivalent to being at a higher altitude than that (usually about 6000-8000 ft). Neither are sufficient to be of any help in acclimatising.

In reply to Theho:

Take it slow at altitude, slowly slowly and a rest day every 1000M gained in height, being fitter will help but just because you may be fitter still take it slow at altitude, if you dont feel good rest, if feeling bad go down till you feel better and rest before going any higher

In reply to maxsmith:


I think medically 'high altitude' begins at 8,000ft / 2440m. So Snowdon at 1085m is well short. Your body handles the low pressure fine up to 2500m or so for regular moving around, then above that needs to make changes to continue functioning well. Most people don't even notice until 3300m or so, though plenty feel it lower.

The physiological effect I mention is, as I said about 'sprinting', only noticeable if you were to compare minute stats at the highest level of exertion. It's practically irrelevant, if even traceable, if just standing, walking or sleeping on top. Maybe if you studied sprinters, for example, running flat out at sea level then flat out at 1085m you might notice a slight drop in performance, if only very temporarily. For the purposes you mention, this effect is almost nil.

In reply to maxsmith:

[O2]: at sea level 100%; at top of Snowdon(1085m) 88%; at top of Mt Blanc (4810m) 57%; at top of Aconcagua (6962m) 43%; at top of Everest (8848m) 33%

You will notice a difference if you try to run around on top of Snowdon having gone there from sea level.
Most people will start to show some altitude symptoms if they go from normally being at sea level to c.3000-4000m.

In reply to Dave the Rave:



Golden Virginia for me.....rolling up at altitude allows you to assess for peripheral neuropathy, temperature, cognitive function and hydration levels. All good stuff plus a decent chance for a breather!
I also agree with the 'cracking on' mentality....being able to suffer a bit is par for the course at altitude or in cold weather and flogging up hills with a hangover is great 'training' for that!

In reply to Robert Durran:
AMS and the other altitude related problems are caused by the reduced oxygen partial pressure (pO2).
Although the same percentage of air is oxygen at altitude as at sea level (21%), due to the overall reduction in pressure (about 100kPa at sea level, so pO2 is 21kPa) the partial pressure of oxygen is reduced at altitude (e.g. the atmospheric pressure at 6000m is about 50kPa meaning the pO2 is about 10kPa).
The same effects have been generated in experimental conditions in hypoxic oxygen tents at sea level with normal pressure but low oxygen (e.g. 12%).

In reply to JJL:

thanks, surely losing 12 % of your O2 would start some physiological changes?

In reply to Theho:

Sleeping on top of Snowdon?!

Sleeping on top of Snowdon will make no difference whatsoever.
However, sleeping on the killer mountain that is Mount Snowdon definitely will...

In reply to JJL:

[O2]: at sea level 100%; at top of Snowdon(1085m) 88%; at top of Mt Blanc (4810m) 57%; at top of Aconcagua (6962m) 43%; at top of Everest (8848m) 33%

The percentage of Oxygen remains the same at all altitudes. It's the lower air pressure that makes the Oxygen less effective.

In reply to FactorXXX:

The amount of oxygen per volume is what he's quoting. So a lungful of air at the top of Everest will yield 33% of the oxygen it would at sea level, because a lungful of air up there will only be 33% mass of what a lungful is at sea level.

The "effectiveness" of the oxygen is the same, you just have less to start with because the body equalises to the outside pressure and so the air density inside the lungs it's the same as that outside, otherwise they would burst.

That's one of the reasons simple oxygen starvation is not enough to acclimatise, you'd need a hypobaric chamber to be able to do it properly.

In reply to abr1966:



There's only me and you sane bud!

In reply to FactorXXX:



Yes, I know; I was trying to indicate the concentration relative to sea level - the atmosphere isn't 100% oxygen at sea level you know...

In reply to splat2million:


Yes, but is it the lack of oxygen or the lack of pressure that makes me feel ill?

In reply to Robert Durran:


It's the reduced oxygen due to the reduced pressure.

In reply to Dave the Rave:

So if the percentage oxygen is reduced without reducing pressure, the symptoms will be the same?

In reply to Robert Durran:
I would say yes.
What I'm trying to explain is that it's ' the partial pressure of oxygen outside the alveolar membrane that causes it to diffuse in to the blood, as the partial pressure of 02 is less in the alveolar blood capillaries. As this reduces at altitude, there is less partial pressure of 02 in the alveoli to cause diffusion across the alveolar membrane into the blood'
It's called external respiration I think?

In reply to Dave the Rave:


Yes, I think I understand that, but what I had thought was that it is not just oxygen deprivation per se which causes the symptoms, but that pressure imbalances themselves did, perhaps by exerting pressure inside your brain to give a headache. Or is the headache simply the brain's way of telling you it needs more oxygen to operate properly?

In reply to Robert Durran:

So to answer your question yes. If somehow the amount of oxygen in the air is reduced at normal sea level air pressure , then the symptoms would be the same as those of reduced P02 at altitude.

In reply to Robert Durran:


I would say that your last sentence is correct, as all cells need oxygen to maintain homeostasis. Headaches could also be dehydration related, which is hard to maintain when working hard in a dry atmosphere at altitude.
Inter cranial pressure may also be affected at altitude. Ie. More positive pressure intercranially and less externally, so this may be the cause of headaches too.

In reply to Dave the Rave:

The brain is within a closed space inside the skull so the actual atmospheric pressure doesn't have much direct effect on it.

Although the exact mechanisms are a source of a bit of debate, there are some fairly good theories about it. Symptoms are caused by low oxygen levels in the blood:
Hypoxic (low oxygen) blood in the arteries supplying the brain cause them to dilate (a physiological response to attempt to improve oxygen supply to the brain) and raises both pressure and flow of blood to the brain. Increased blood flow and pressure, as well as increased permeability of the blood brain barrier (through mechanisms I'm afraid I don't understand) causes fluid to leak out of the arteries and accumulate in the tissues of the brain. In the early stages this causes the symptoms of AMS and later cerebral oedema.
Pulmonary oedema is a somewhat different mechanism - the arteries of the lungs constrict with hypoxia (a useful mechanism if you have some illness like pneumonia, but not good when the whole lung does it because of low partial pressure of oxygen in the air). This increases the pulmonary (lung) blood pressure, causing stress and damage to the capillaries. This allows fluid to leak in to the alveoli, and creates inflammation which causes further fluid leak.

With a bit of knowledge of scientific vocabulary, this paper explains it far better than I can:
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(03)13591-X/f...

In reply to Robert Durran:


No

In reply to FactorXXX:


Where did you get these statistics from out of interest?

Do you have a value for the top of the Ben?

In reply to Theho:

https://en.wikipedia.org/wiki/Barometric_formula


Ben Nevis 1344m, 86%


Edit - to add barometric formula

In reply to splat2million:

Good source, thanks.

Isn't a key line in that abstract is "mechanisms accounting for *exaggerated* pulmonary hypertension in HAPE" (asterisks added)? Some degree of PH is going to happen purely by an increased pressure differential from normal blood pressure to external pressure. This will result in fluid loss into the lung (although the air is also drier generally, so evaporation from the lung also increases).

So both the inflammation and the pressure difference will result in more fluid in the lung and, as oxygen absorbtion is a passive process and obeys a 1/r^2 law, a small increase in diffusion distance has a marked effect on the amount of O2 reaching the capillaries.

The O2 shortage in the body from HAPE is as much a consequence of the fluid as a cause of it.

In reply to Dave the Rave:


I don't think that's true - see above

In reply to JJL:

Unfortunately, not all of that's true...as splat2million suggests, the pulmonary oedema in HAPE is a high protein - ie inflammatory - one, rather than just due to fluid leaking across. Whilst things are still not completely understood, splat's abstract is 13 years old so things have moved on a bit. What is thought to be the main mechanism is that the reduced partial pressure of oxygen causes the medium sized pulmonary blood vessels to constrict; this causes an increase in pulmonary blood pressure (usually described as PAH or PH). This increased blood pressure gets transmitted to the smaller blood vessels (capillaries) which are damaged as a consequence. These then leak inflammatory fluid into the alveoli (the sacs where gas exchange takes place) & the terminal airways. This is somewhat similar to the mechanisms behind Acute Lung Injury & neurogenic pulmonary oedema. There is probably a (small) role for the reduced barometric pressure but not much (and anyway the lower Reynold's number for air at altitude would presumably mean flow into the lungs is easier). Don't forget if you're only getting half the amount of oxygen in (at, say the top of Mont Blanc), you're going to have to double your work of breathing to get back to where you're used to...
and the fluid (whatever kind of fluid) getting into the alveoli & terminal airways doesn't cause a diffusion barrier, it causes those elements to collapse (and therefore stop performing any gas exchange); and you don't evaporate water from your lungs, but from your nasal passages & the back of your throat
Hope this helps

lardbrain

In reply to Mr Lopez:


https://www.altitudecentre.com/rent/ihe-systems/ or one of these?

In reply to Removed User:
Interesting. So, not just O2 pressure seems to be the conclusion and we don't know the relative importance of the different elements. I'm pretty sure a longer diffusion path is unhelpful! Also that inhaling very dry air and exhaling damp air will cause water loss not just from throat?

In reply to JJL:

Absolutely - in some disease states, a longer diffusion path is indeed unhelpful, but with oedema the key is the fact that the alveoli would normally collapse (& then would not re-inflate) because of Laplace's law and the surface tension of water (normally present lining the alveoli): the lungs have a naturally occurring surfactant which massively reduces the surface tension. Once you put water/inflammatory juice into those alveoli it reduces the concentration of surfactant and thus stops it working...the alveoli collapse and won't open up...You are right in that you will lose water from elsewhere, but only once you're pretty dehydrated

In reply to Removed User:

Thanks. An interesting contrast to emphysema for in some ways similar effect.

In reply to john_mx:

Altitude Centre: Isn't it interesting that none of their "research" seems to be directly relevant to the question which is based on practical aspects of acclimatisation for a normal person going to Nepal for a couple of weeks with, presumably, some trekking.There seems to be no evidence quoted from reputable peer reviewed journals relevant to the average trekker. Their programmes cost a lot which would be better spend enjoying Nepal at any altitude and if spend going higher slower would truly be money well spend with a good evidence base.

As for their Alitvits.............these have been the laughing stock of the mountain medicine community throughout the world and are frequently quoted in lectures as being worth looking at purely for entertainment value.

David Hillebrandt

In reply to Theho:

Theho,

As always your sensible acclimatisation question has started a long and mostly irrelevant discussion. some of the replies are medically sound, some are rubbish, some are based on untested theories, some are very technical (some correct and some not). The best may be said to be the humorous ones. A fag, a cup of tea and a stiff upper lip did work to some extent in the 1930s.

Now some facts:

A night or two on Snowdon will not help physiologically but psychologically it can be great fun if the weather is good.

Food make negligible difference and the beetroot theory is just theory and has no practical evidence.

Laboratory pre acclimatisation makes little difference unless you happen to be super fit, operating a the top of your performance level and willing to spend hundreds of £ prior to departure and most likely giving up your job to have sufficient time. It is a commercial con. Spend your money in Nepal going slowly in a fantastic culture.

If only out for two weeks why not visit some of the lower hills enjoying trekking in a less crowded area where you will see few Europeans and meet more locals?

If you have never been high before and do not know how well you acclimatise do not take Acetazolamide since you may not need it. If you have had acclimatisation problems before see an experienced mountain medicine doctor to get advice prior to your trip.

For list of experienced doctors in the UK see www.medex.oeg.uk . Read their free advice booklet . Also check the Advice papers on the UIAA website.

Have a good trip. Take it slowly and enjoy it.

David Hillebrandt
Medical Advisor to BMC

In reply to Theho:

Long days hillwalking, preferably several days in a row, will help with the continuous trekking aspect.
If this is your first time to Nepal / altitude then treat it as a learning experience where you may / or may not get to 5,000 metres but you will have a much better idea of what to do the next time you go. Go to enjoy and learn rather than make a specific altitude your target.
There is no short cut to acclimatisation and different people seem to acclimatise at different rates. Many people cope with 5,000 metres over about 7-10 days if they acclimatise carefully, but not all!
If you are investing a considerable sum of money going to Nepal for only a couple of weeks you could take a trip to the Alps and ski / snowboard at a high resort for a week or two if you can ski / snowboard or, if all else fails, wander around in a lift station / hut as much as you can assuming you are not an 'alpine climber'. Not ideal but something that may help.

In reply to Simon4:

' The best may be said to be the humorous ones. A fag, a cup of tea and a stiff upper lip did work to some extent in the 1930s.'

Told ya

In reply to Theho:

Many thanks for all the advice.
I've been at altitude a fair bit in the past and have struggled on some trips and seemed to acclimatize quite quickly on others.
From all the responses it seems there is little to be done in the UK other than the usual. I have heard many times that smoking helps, presumably to get your body used to varying quality of air, but not prepared to sacrifice my health for that chance!

Thanks again.

In reply to Theho:

Another vote for Diamox in addition to slowly slowly....

Every body is different and it works for me as a back up. Then again, it might just be an effective placebo! The mental aspect is quite important when you've got something big planned and lots of time/money/effort riding on it.

In reply to Damo:


Whilst I understand where you are coming from to be precise the opposite is actually true. Athletic sprint events are quicker at altitude, and I think times ran at over 1000m altitude are excluded from most 'world records' (or at least have an asterisk next to them). Have a look at the times from the '68 Olympics in Mexico City with records broken in most of the track events up to the 400m IIRC.
Track cycling being the other obvious sport which is 'quicker' at altitude irrespective of distance.

For middle distance events and longer (aerobic events) then of course altitude will negatively affect performance and I'm sure you are quite correct. Sorry for being a pedant, I knew what you meant but find it quite interesting

In reply to Theho:
I have heard that decent amounts of garlic introduced into your diet at least several days beforehand helps a lot with acclimatization. Apparently it's what the Nepalese do (in the form of garlic soup every day).

Garlic (unlike beetroot juice) is known to have definite effects on blood pressure (usually lowering it, whether it's initially high or normal). But I can find at least one study that claims it doesn't do much for hypoxic (low oxygen) exercise: http://www.ncbi.nlm.nih.gov/pubmed/23713527

However as mentioned before, hypoxic conditions are not the same as low air pressure conditions, and neither does one study fact make, it's possible that any benefits are only from hours of aerobic exercise (I believe this study was essentially anaerobic) and lastly it's possible the benefits are not during the exercise phase, but during the healing phase from prolonged exercise (i.e. during sleep) - so I'd say it's still unknown whether it has any effect at all beyond placebo, but it probably can't hurt if you don't have any blood pressure issues and might get you used to Nepalese garlic soup

In reply to Aly:


No, you're right and I knew I was being lazy when I wrote it, with Mexico at the back of my mind. What I was driving at was a high or maximum expenditure of effort (not walking around a ski resort at 2500m) and a corresponding measurable decrease in performance - but I should have used an example that lasts more than 40 seconds, which sprints do not. I was trying to envisage something that could theoretically be done on the top of Snowdon i.e. not rowing

It's worth noting that the faster sprint times (and particularly jump records) are due to less air resistance, the impact of which is greater than any internal physiological process. Your body getting less O2 doesn't actually make you faster!

In reply to Damo:

The key distinction here is that sprinting is anaerobic, so oxygen makes no difference.