DEPENDENCE OF OXIDATIVE BALANCE AND CHOLESTEROL METABOLISM IN MUSCLE TISSUE ON EXERCISE INTENSITY

Intriduction. Changes in oxidative balance and lipid metabolism have the leading role in performance limitation, adaptation and maladaptation to physical activity. It is especially important to analyse the direction of metabolic changes at the subcellular level. The aim of the study is to examine the state of oxidative balance and cholesterol metabolism in muscle tissue at moderate and maximal swim-ming load. Material and methods. A comprehensive study of indicators for free-radical oxidation (content of diene conjugates, TBA-active products, chemilu-minescence intensity), antioxidant defense (total antioxidant activity, antiradical activity) and cholesterol metabolism in tissues of heart muscle and thigh muscle of white male rats at moderate and maximum swimming load was carried out. Results. The patterns of metabolic changes in muscle tissue depending on the intensity of muscular work have been established: these are the forms of compensated oxidative stress at moderate and decompensated at maximum load, against the background of decreasing cholesterol content. In cardiac tissue oxidative stress phenomena were less expressed, and changes in cholesterol content were multidirectional: a tendency to decrease at moderate load and a significant increase at maximum load. Conclusion. The reduction of antioxidant defence resources and intensification of free-radical oxidation reactions constitute one of the leading mecha-nisms for metabolic disorders due to extreme physical load, which is confirmed by reliable changes in the studied parameters. The complex study of indicators characterizing the processes of free-radical oxidation, antioxidant protection and cholesterol content is an informative criterion for the influ-ence of physical exercise on the organism. The obtained data allow us to recommend the inclusion of antioxidants in the complex prevention and ther-apy of acute physical overstrain.