Tempo Aclimatação Altitude

Altitude acclimatization: gain ≤ 500 m/day above 2,500 m

Past 2,500 m the oxygen partial pressure drops and the body may react with Acute Mountain Sickness (AMS), which shows up as headache, nausea, fatigue and insomnia. Above 4,500 m AMS can turn into HACE (High Altitude Cerebral Edema) or HAPE (High Altitude Pulmonary Edema), both life-threatening emergencies. The usual acclimatization rule keeps you to no more than 500 m of sleeping altitude per day above 2,500 m, with a rest day every 1,000 m of gain. For reference, cities sit at La Paz 3,640 m, Cusco 3,400 m and Quito 2,850 m, while mountains reach Aconcagua 6,960 m and Everest 8,849 m. Acetazolamide (Diamox) speeds the process up, and Sherpas carry a genetic adaptation tied to the EPAS1 gene. Take a target of 3,500 m: from a 2,500 m baseline you're looking at roughly 2 days minimum.

Applications

Mountaineering and high-altitude trekking (Everest, Aconcagua, Kilimanjaro), planning a trip through the Andes and Himalayas (Cusco, La Paz, Lhasa), high-altitude sports training, mapping out a ski resort itinerary, expedition medicine, and occupational safety for miners and astronomers who work at altitude.

FAQ

What is the golden rule of acclimatization? "Climb high, sleep low." You can hike higher during the day, but where you sleep shouldn't be more than 500 m above the previous night.

Does fitness prevent altitude sickness? No. Susceptibility to AMS is largely genetic and has little to do with conditioning, so well-trained athletes get sick just like anyone else.

What is the emergency treatment for HAPE/HACE? Get down at least 500-1,000 m right away, with supplemental oxygen and dexamethasone/nifedipine if you have them. Waiting kills.