I guess this discussion really is just a replay of that earlier one on the same topic a few years ago. In fact, Malmo, I was going to (and do) agree whole –heartedly with what you said because it sounded like something I would have said and then it turned out I did; man, what age does to the mind.
It is possible to agree or disagree with many things about altitude training, but a couple things seem fairly certain. (1) you can’t perform an endurance running event as fast at altitude as you can at sea level (please note, I didn’t say cycling or speed skating, but I will include swimming along with running). (2) training at altitude will improve your endurance performance at altitude – partly as the result of some physiological adaptations, and to a good extent as a result of learning to compete at altitude (if you want to race your best in any event at sea level then you need to race a few times over that distance at sea level; if you want to race your best at altitude you need to race a few times at altitude).
Beyond these two, things get a bit more sticky. I have been fortunate to have had some good runners as subjects in my altitude studies – Ryun, Von Ruden, McCubbins, Nightingale, Young, Lindgren, Werthner, Bacheler, Reilly, Day, Bell, Schul, Moore, Smith, Clark, Patrick, just to mention those who were Olympians (and I definitely consider Bill Clark and Dave Patrick to be Olympians, but that is another issue). I only mention these because in our earlier research we used less-elite runners and were criticized for not using elite runners. However we got pretty similar results regardless of the caliber of subject. An elite example -- after 4 weeks with us at altitude, Ryun flew down to California and broke the world record in the mile. For all we know he would have run as fast or faster after 4weeks in Monterey Bay. I do tend to say that at least the altitude training didn’t seem to hurt, but are we sure, may the time have been even better without those 4 weeks at altitude?
What about high/low sleeping/training? Wow, I dread the day the East Africans find out about that, but I guess the supporters of that idea will just say it won’t work on the Africans because they have been at altitude for umpteen generations (even though umpteen hasn’t been enough for the Bolivians and Peruvians).
Seems this all started with the 68 Olympics when the East Africans did well at the Mexico City Olympics. Then they continued to do well in sea level races and it was time to jump on the band wagon. So next thing to happen was for top sea-level athletes to move to altitude and continue to be the best, which of course prompted everyone to assume they got good because of the altitude (without wondering the possibility of maybe having gotten as good or better without the altitude).
I often find myself arguing with myself about this whole altitude thing – a coach arguing with a research scientist. We hear that you lose speed at altitude. How is that possible if you can run faster at altitude than you can at sea level (the old less-dense air factor). Here we as coaches get the scientists completely confused. OK, you can’t run long intervals or threshold runs as fast at altitude as at sea level, but for some reason the scientists are calling threshold and interval training “speed” work. As a coach I think of running fast as speed work, but don’t think of comfortably hard, or even hard running as “speed” running.
And then there is the issue of changes in blood with time at altitude. If there is a certain increase in hemoglobin and hematocrit as a result of altitude training, must we test everyone before going to altitude and anyone over about 48 HCT can’t go or they will go beyond the legal (50) limit when the altitude produces that certain increase in HCT. I realize 50 is not a disqualifying number for runners, but I think it is in some sports. I’ve had groups of elite and hard-training endurance athletes show zero change in blood parameters with time at altitude. I have also seen many positive reactions to altitude training, but can we be sure it was the altitude? What does a serious runner look for when deciding on a training site? Nice weather; good facilities and training venues; good support services; healthy, friendly atmosphere; understanding people to train with and be coached by. How many of these things are you willing to sacrifice in order to be at altitude instead of a low-land training site with all of the above. Would an altitude site, with all these things be better or equal?
Lots of variables to consider. Heck, the Arizona Cardinals train in Flagstaff for pre-season each year, but hard to say if it pays off. But I will tell you one thing, it’s far better here than in 110 degrees in Phoenix.
The final thing I like to address is that issue of when to best compete at sea level following altitude training. We often hear that you have a relatively narrow window of time upon return to SL, for best SL performance. I have seen numerous runners continue to improve for months (no, years) after return to SL. Confusing factor is that often low-land runners train at altitude for a specific sea-level championship and once that is over they reduce training, and then we read that not too long after return to SL they lost their altitude benefits. Well, I imagine if you were training 120 a week for months and then reduced that (along with reducing quality workouts), that you would also not run so fast after some time on the reduced training stress. If altitude training results in an improvement in fitness, then you must continue to challenge your fitness upon return to SL in order to hang on to that which you achieved.