Exaggerated fear constitutes stress and therefore a great loss of energy. Don't waste your energy, it is fundamental for adaptation. An explanation of exactly how fear acts on an organism would be very complicated, but that fear can produce a fast pulse, just as if you were exercising is a good example. Your organism is immune to the bacteria and viruses that surround you in your usual habitat and not to those of a new environment. You should not ingest unknown foods in great amounts for the first time upon arrival.
Digestive enzymes develop a specific capacity and function for each type of food.
Although some foods taste very good, one should NOT stuff oneself the first day. In addition, tobacco products and alcohol should be avoided. 2.- Adjustment to high altitude is complex and varies greatly between individuals, and in different trips for the same individual. However, tolerance to high altitude does not depend on physical strength. It was later learned that as children, they had suffered from pulmonary disease that after recovery was asymptomatic at sea level.