Gain the Skiers Edge by Eating Right in the Mountains The aim of this article is to discuss how physical activities at high altitude can potentially affect nutritional requirements. Medium altitude is defined as (1500-2500m) at this altitude oxygen saturation remains above 90% but altitude illness is possible. At high altitude (2500-5300m) oxygen saturation falls below 90%, altitude illness is common and acclimatization is necessary. As a point of reference oxygen saturation in Boulder, Colorado (5400 ft) is approximately 94%. Alpine skiing in the North American and Canadian Rockies commonly occurs at or above 3000 meters (9842 ft). Skiers who live in ski country are subject to decreased performance but those that fly in from sea level suffer even more. Maintain Hydration: It is easy to become dehydrated in high-altitude environments. Dehydration increases the risk of frost bite and worsens the fatigue, impaired judgment and apathy of hypoxia. The body's requirement for fluids is very high at altitude; often exceeding 4 liters of water per day. Altitude increases water losses from the lungs due to the cold, dry air. There is also increased urinary loss of water because altitude and cold have diuretic affect. Sweating adds to the water loss....