Just using a LOT of water is a bad idea (unless you eat a good amount, with salt and other nutrients around that time). Because as we all know, this can lead to hyponatremia (at the risk of stating the obvious: you sweat out a lot of salt with the water you lose. Only replacing the water dilutes your blood (serum).
As altitude  increases, the air becomes less dense because of the smaller amount  of air above that altitude. There is a corresponding decrease in  pressure with an increase in altitude. Eventually you reach a point  without air, and the pressure decreases to zero. That is space. + 91 others found this useful.
The effects of high altitude on humans are considerable. The percentage saturation of haemoglobin with oxygen determines the content of oxygen in our blood. After the human body reaches around 2,100 m (7,000 feet) above sea level, the saturation of oxyhemoglobin begins to plummet.ountain medicine recognizes three altitude regions that reflect the lowered amount of oxygen in the atmosphere: 1  High altitude = 1,500â3,500 metres (4,900â11,500 ft). 2  Very high altitude = 3,500â5,500 metres (11,500â18,000 ft). 3  Extreme altitude = above 5,500 metres (18,000 ft).