Acclimitization involves adapting to the changing concentrations of oxygen in the air as altitude increases.

The amount of oxygen available to climbers is determined by atmospheric pressure. An increase in altitude results in a decrease in atmospheric pressure. This creates thinner air with fewer oxygen molecules available for breathing. The atmospheric pressure at the summit of Mount Everest (29,028 feet) is only a third of that at sea level. Therefore, it is critical for climbers to regulate their breathing in order to sustain an appropriate concentration of oxygen in the blood. However, what constitutes a regular level of oxygen varies from one individual to the next. In fact Sherpas, the native inhabitants residing near Everest, are genetically predisposed to high altitude climbing. Most can ascend to 23,000 ft (or Camp 4) without the aid of oxygen.

Changes in the concentration of oxygen affects how a climber's body seeks oxygen. As oxygen levels in the air fall, the body increases blood flow to the brain. Sometimes, the body over reacts and blood vessels leak fluid into the brain. The brain swelling that ensues results in symptoms of Acute Mountain Sickness (AMS). (More information)

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March Networks is working with Algonquin College to capture vital sign data of the climbers on this web site.

Tune in to the Tracking the Climb: Telehealth section of the web site. Updates will begin when the team ascends to higher altitude.

Also read about an exciting neurological research project involving the Everest 2004 climbers and Brown University. This study has implications for space travel and the treatment of Parkinson's Disease.