SEASONAL CHANGES OF EXTERNAL RESPIRATORY PARAMETERS IN SKIERS OF MASS CATEGORIES IN THE CONDITIONS OF RUSSIAN NORTH
The study results of lung volume seasonal changes in skiers of mass categories in the conditions of European North are presented. Respiratory system study was carried out in September, January, April and July in the same group of 38 men skiers aged 18-22 (middle age: 19,6 (19,2; 21,7)), born and permanently residing in Arkhangelsk (64°32'n.l., 40°32'e.l.) and Severodvinsk (64°34'n.l., 39°51'e.l.). Survey sample had experience in cross-country skiing for 3-5 years and 1-2 senior degree. Spirograph «Dinamit-С» (Complex КМ-АР-01) was used for pulmonary function test. Lung volume was esteemed: respiratory volume (RV), inspiratory (IRV) and expiratory (ERV) reserve volume, inspiratoty capacity (IC), lung capacity (LC), as well as indices of lung ventilation: respiratory rate (RR) and respiratory minute volume (RMV). It is stated that skiers have seasonal functional alternation in the external respiration system. Thus, LC maximum was in winter, LC minimum - in spring, with difference 1,21 l. RV minimum was in summer, maximum - in winter, with difference 0,58 l. IRV was maximum in autumn, ERV and IC - in winter. Not only statistic lung volumes indices, but their nature of communication change in seasonal dynamic in surveyed sportsmen skiers. Percentage ratio calculation from RV to LC showed that breathing in rest conditions skiers use from 17 % in autumn and summer to 21-23,5 % LC in winter and spring. Comparison of the results obtained in skiers and people not engaged in sport activities revealed that seasonal changes of lung volume in skiers are more evident.