SEASONAL VARIATIONS IN METABOLIC PARAMETERS, OXYGEN TRANSPORT SYSTEM AND EXTERNAL RESPIRATION IN SKIERS FROM KHANTY-MANSIYSK

Abstract

Aim. This paper investigates seasonal variations in metabolic parameters, oxygen transport system, physical performance, and respiratory function in skiers from Khanty-Mansiysk. Materials and methods. A two-phase seasonal study was conducted on 32 young skiers. The study periods were defined as the autumn phase (from October to November) and the spring phase (from April to May). Physical assessments included a complete blood count and blood biochemistry; a treadmill ergometer test; and pulmonary function testing. Results. Statistical analysis revealed significant (p < 0.05) seasonal changes in multiple physiological parameters between spring and autumn. Hematological parameters: decreased levels of erythrocyte count, hematocrit concentration, hemoglobin concentration, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. Biochemical markers: increased levels of total bilirubin, cortisol, and vitamin D; reduced levels of total protein. Respiratory function: increased relative values of maximal oxygen consumption, reduced values of forced vital capacity, peak flow rate, and forced expiratory volume in one second. Regression analysis revealed that forced vital capacity exerted the greatest influence on maximal oxygen consumption in autumn; peak flow rate was the primary predictor of maximal oxygen consumption in spring. Conclusion. The study demonstrates seasonal cycles in physiological systems among skiers. Stressful periods occur at the beginning of each season, with the most significant changes observed several months into the transformation period.