The Acclimatization Thermal Strain Index (ATSI): a preliminary study of the methodology applied to climatic conditions of the Russian Far East.

Travel to distant places where the climate is different to that at home involves a period of short-term acclimatization adjustment following arrival during which the traveler might experience thermally-induced physiological strain. This may be expressed as an "acclimatization thermal loading" (ATL). The first signs of this show up in the respiratory organs. In the current study, the Acclimatization Thermal Strain Index (ATSI) is developed and used for assessment of ATL for recreational travel over a range of climatic conditions. ATSI estimates the impact of short-term acclimatization calculated as the ratio of a difference between respiratory heat losses at the traveler's home location to respiratory heat losses at the trip destination upon first arriving there. The Russian Far East region is used as a case study. The research focuses on the effects of travel from two locations in the study region. The results show that ATSI values can be significantly different when considering places of trip origin. For example, travel from Anadyr to other locations within the Russian Far East could lead to large ATSI in summer. In contrast, ATSI values are small for travel almost anywhere in the region during winter, but this is against a backdrop of extreme cold for the region as a whole. Here, the diversity of climatic conditions of both heat and cold means short-term adjustment to conditions could be stressful or worse for those who travel to participate in outdoor activities.