I'm going to Colorado to visit a friend and we will be going on a week long trek across a couple of 14'ners. I'm looking for some ways to help prepare my body for trip.
[Edited after comments and additional research.]
Aerobic training will not prepare you for altitude
Some of the answers here are misleading. According to the Altitude Research Centre:
Being physically fit does not prevent you from experiencing AMS (Acute Mountain Sickness) symptoms. There does not seem to be a link between fitness level and susceptibility to altitude illness.
Altitude sickness is a significant risk at 14,000 feet (4,200m)
At 14,000' (4,200m) you're only getting 60% of the oxygen at sea level. Altitude medics classify 14k as "Very High Altitude" which is a strong hint that the dangers are significant.
Susceptibility to AMS appears to be genetic and varies widely between individuals. Estimates of incidence levels are all over the place in the literature, but we can safely say that a significant percentage will experience quite severe physical and cognitive issues if they ascend rapidly to 14k.
Don't underestimate the impact. Even mild AMS is extremely unpleasant and can affect your ability to move safely on technical ground. Severe symptoms can be pretty much paralysing. I'm very susceptible to AMS and know this from experience.
So it's important to follow the Golden Rules and not push on if you experience symptoms. Rapid descent will always resolve early symptoms - the problem is that denial is extremely common as people are keen to reach their goal and not disrupt the rest of the party. This is how the serious issues occur.
Currently, the only way to know your own response to altitude is to suck it and see. So it's important to be cautious on your first high ventures, and pick routes with an easy retreat. Even people with known low susceptibility can suddenly experience problems, so always be prepared to descend if you feel unwell.
How to acclimatise before ascending to 14,000 feet (4,200m)
It's very important to distinguish between two scenarios:
- The typical alpine trip where you make day-climbs to the peak, but descend to sleep below 8000 feet (2400 meters). That is what we are discussing here.
- A trip where you will be progressively sleeping at higher altitudes. This is a whole different ballgame and life-threatening problems are quite common. Do your research and understand the proper protocols for gaining height.
The only proven way to acclimatise fully is a programme of training climbs at increasing altitudes. If you know you are one of the lucky ones, you can head straight off to your 14 thousander. For the rest of us, you'll need 1-4 days to acclimatise depending on your physiology.
I'm prone to sickness, so personally I find it best to be conservative and climb up to around 9,000' (2,700m) on the first day while sleeping low. Even this can be quite uncomfortable. Then I'll add 1,000' (300m) or so a day if things go OK. If I'm relatively symptom-free on an 12,000' training climb, I'd feel ready for 14,000' (4,200m). If you're less susceptible, you can accelerate the process. Only experience will tell.
Altitude tents and masks
This is quite an expensive and disruptive process. The equipment can be hired or purchased if you don't have a suitable facility nearby. US Army Research suggests that tents are better than nothing, but are far from a full substitute for traditional acclimatisation. For a 14 thousander, it's unlikely that this will be the way to go.
The only recognised medication is Diamox (Acetazolamide).
Diamox is far from risk-free, with many unpleasant but benign side-effects and occasional life-threatening reactions. And recent research suggests that it is not measurably effective for countering the effects of strenuous exercise during rapid ascent.
In the UK, the clinical authorities recommend against using Diamox prophylactically, so you won't get a prescription. It's available in the US, but the risk/reward ratio doesn't look good and you certainly shouldn't rely on it preventing AMS at 14k.
Edit: I've adjusted the broken Golden Rules link with some that I searched up. I'm not the OP, who knows way more, but they look fairly in line with what previous casual research showed me.
- The dangers of rapid ascent to 14k are significant
- Only experience will tell you how long you take to acclimatise
- If you do need acclimatisation, the only proven approach is traditional training climbs
- Tents and masks only provide modest benefits, while medication has significant side-effects and may well not work in this scenario.
There isn't necessarily a way to prepare your body for the altitude. You should however:
- Be in good condition overall, i.e. able to handle at sea level more than you are planning to do at altitude.
- Try to spend several days at a lower altitude (like 7000 feet) doing some aerobic activity before trying to go higher.
- Drink more water than usual.
- Take regular doses of aspirin during your trip (or starting before your trip, ideas on this vary).
There is a lot of general information at hiking, skiing, and sports conditioning sites (ex. Wilderness Sports Conditioning).
Finally, know the signs of altitude sickness and make sure your hiking partners do too, so that if anyone starts getting sick, there are people there to make sure that person descends immediately (altitude sick people are sometimes too confused to realize they are in trouble).
Find an area with a large stairway (football field bleachers work great), then power-walk/run up and down them while taking a break every few runs. Keep doing this until the trip, while increasing the number of "laps" when you think you're improving.
When it starts becoming easier, pack up your backpack with your gear or simulate the weight with something heavy, and go at the stairs again (you'll want to power-walk with the backpack). You want to build your endurance, so practice breathing thoroughly while climbing.
Altitude adjustment is primarily conditioned through acclimation. Remember to travel high, sleep low. If you can, go earlier and spend some time acclimating to the higher altitude by going up to a higher altitude and then descending after a period of time. Perhaps a couple hours at the higher altitude before descending to a somewhat lower altitude. From what I am familiar with, physical conditioning is not directly related to the sensitivity to altitude changes.
Its also recommended to train your general hiking skills, get your backpack in order, work in your boots.
Enjoy your trip.
As for raw cardio stairs or stair trainer. Or running, walking, bicycle. Include some walking with a fully loaded pack to get you body used to bearing the weight.
Search on "altitude training".
There are altitude training masks but not everyone agrees they are effective.
There are altitude training tents, rooms, and even sleep tents. A gym near you may have an altitude training tents, rooms
They reduce the oxygen to simulate altitude. The idea is to get your body to produce more the oxygen carrying red blood cells.
There are drugs to produce more red blood cells but not something I would advise. Don't - it can kill you. Before cyclist got good at it many died.
If you can spend just a one or two days at elevation with some light excise before going high your body will adjust.
Look up signs and treatment of high altitude pulmonary edema before you go. If you are crossing a pass maybe sleep in the valley rather than on top of the pass.