“…Key factors influencing the organism and the training process at high altitudes are: decreasing barometric air pressure, decreasing partial pressure of oxygen (pO 2 ), decreasing air temperature (declining by about 1°C for every 150m of increased altitude), decreasing humidity, and increasing radiation (ultraviolet radiation increases by 20-30% for every 1000m (Basset & Howley, 2000;Katyama et al, 2003;Gore et al, 2001;Green et al, 2000;Levine et al, 2005;Morrison & Cooper, 2006;Neumann et al, 2000). The process of acclimatization at higher altitudes depends on the following factors: training level before arrival, physical condition, health and mental stability, altitude of the stay, altitude of personal workout, length of stay, volume and intensity of training load during stay, season and stage of preparation within the framework of the annual macrocycle, and drinking and dietary régime (Noakes, 2003;Green et al, 2000;Bragada, 2010).…”