In reply to Roberttaylor:
climbing is the best training for climbing.
but not the best training for steep approaches with heavy packs, hauling, altitude, recovery and stress.
the old cliche of training with a plastic bag over your head is obviously not practical, but its an indicator that to train for altitude is a departure from regular endurance training.
trail running is a good base method. increasing the load you carry and the steepness of the routes goes a long way to conditioning the musculature and alignment that will be part of steep approaches with big steps up rocky trails.
twight i think has a good angle on it all when you get past the pseudo-commando/henry rollins bluff. extreme alpinism and gym jones fill a gap that seems to work well enough for house-anderson so thats a pretty good reccomendation.
i think to model some of your training on that but to stretch it out for 2 or 3 hr sessions (whereas GJ sessions are usually about half that and cross fit is even shorter).
half of altitude is about hormones and thats pretty genetic - not much you can do about that.
much of whats left is directly related to CV and oxygen uptake when engaging large muscle groups and your ability to be efficient.
thats where just climbing without altitude falls short. youre simply not stressing your system enough beyond what its used to.
for me, thats where i hit gym style training - but not cheesy circuits and hours on a treadmill.
better still, a home made set up with some bars, heavy stones a big rope and access to a paddock will fulfill your needs better.
when it comes to actual training, anything that stresses your breathing reflex will help - and pretty much any exercise can do that with some adaption. using the biggest muscle groups possible to move the heaviest weight you can for several repetitions with strictly controlled breath counts does a lot to condition your systems response to less oxygen.
be warned, its not pleasant.
work out a series of 4 or 5 exercises that you think replicate the moves of alpine climbing and just get into them. for me hauling a sprint sled, upright rows, carrying heavy rocks, squat throwing a medicine ball and mixing pull ups and weight presses works, but theres a million versions.
its really neanderthal stuff, but actually makes a difference.
its important to keep running tho as without it you might increase muscle mass beyond what you want which can be counter productive.
the running too is vital for adapting your body to utilize fat more efficiently - keep things slow.
dont fixate on it tho. a few climbing sessions a week, running and time out to be human keeps it all pretty real.
im sure theres also better ways than what i think too.
sorry to carry on, this stuff interests me and i can get a bit over-involved.