Unfortunately I've encountered a few volunteers that after a couple of days of hard work were rendered useless.
That might be the work and not the altitude. LOL
Full acclimatization actually takes several weeks, but several days goes a very long ways to benefitting the moderate altitude hiker/climber/worker. Your schedule is conservative and commendable, and needed by many people. It's the one or none night people who are at the most risk.
From this high altitude tutorial
http://www.ismmed.org/np_altitude_tutorial.htmare the following suggestions:
The key to avoiding AMS is a gradual ascent that gives your body time to acclimatize. People acclimatize at different rates, so no absolute statements are possible, but in general, the following recommendations will keep most people from getting AMS:
- If possible, you should spend at least one night at an intermediate elevation below 3000 meters.
- At altitudes above 3000 meters (10,000 feet), your sleeping elevation should not increase more than 300-500 meters (1000-1500 feet) per night.
- Every 1000 meters (3000 feet) you should spend a second night at the same elevation.
Remember, it's how high you sleep each night that really counts; climbers have understood this for years, and have a maxim "climb high, sleep low". The day hikes to higher elevations that you take on your "rest days" (when you spend a second night at the same altitude) help your acclimatization by exposing you to higher elevations, then you return to a lower (safer) elevation to sleep. This second night also ensures that you are fully acclimatized and ready for further ascent.
