Ogni persone è diverso. Conosco gente che sta male (male davvero) già a 2500m anche salendo lentamente. Altri arrivano ben oltre 3000m e stanno benissimo. Arrivando a La Paz (4000m) in Bolivia c'è chi scende dall'aereo e sviene (tengono sempre bombole di ossigeno nella zona arrivo
), mentre altri prendono su i zaini e bagagli da 20-30kg in spalle e camminano bene (per fortuna io sto nel secondo gruppo 
).Visto che il trasporto del ossigeno dipende dal processo di saturazione attraverso la emoglobina contenuta nei globuli rossi, e visto che la quantità della emoglobina dipende dalla quantità di ferro, è probabile che stati di anemia, anche leggeri, possono influenzare in modo negativo. Vice versa avere sufficienti livelli di ferro possono aiutare.
Tratto da un sito di "consigli per "Sports Fitness".
"How can athletes who live at sea level prepare for a competition at altitude?
One approach is to compete within 24 hours of arrival at altitude. Not much acclimatization will have taken place but most of the classical symptoms of altitude sickness will not have had time to manifest. After the intial 24 hours, dehydration and sleep disturbances become more prominent.
An alternative option is to train at a higher altitude for at least 2 weeks prior to competition. Although full acclimatization to altitude takes 4 to 6 weeks, many of the physiological adaptations occur in the first 2 weeks and the more severe disturbancs should have settled. It is important to remember that during the intial days at altitude work capacity is reduced, so athletes should train at 60-70% of sea level VO2 max and build up gradually over 10-14 days.
A third approach is to devote a greater percentage of training time at sea level to endurance training several weeks prior to competition. This is a strategy often adopted within many team sports, helping to raise players' VO2 max to a peak so that they can perform at a lower relative intensity without significant loss in performance.
Sleeping in altitude tents and hypobaric chambers may be able to adequately simulate the effects of altitude but these tend to be very expensive. Unfortunately, there is no evidence to suggest that spending 1-2 hours per day breathing hypobaric gases at sea level results in the same adaptations as living at altitude."
E ecco il link al sito se qualcuno vuole leggere tutto l'articolo.
http://www.sport-fitness-advisor.com/ac ... itude.html
