TY CONF TI THE EFFECT OF PRE-TRAINING ON ACCLIMATIZATION IN THE MOUNTAINS KW acclimatization KW training KW breath holding KW hypoxia KW physical preparation KW stable phase JO MODERN TECHNOLOGIES AND SYSTEMS IN TRANSPORT: PROBLEMS AND PROSPECTS AU Grigoreva, I.V. AU Volkova, E.G. AU Protopopov, A.M. PY 2026 PB FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov