Age-related changes in microcirculation: the role of regular physical activity
Background: The role of age-related changes in adaptive responses of the circulatory system is well known. The most important part of the cardiovascular system is the microvascular bed, where tissue perfusion and transcapillary exchange are carried out. Specific requirements impose a muscle load on the circulation. A quantitative assessment of the microcirculatory bed before and after its impact allows us to assess the reserve capabilities of the microcirculation system. The aim of the study: To study the microvascular bed and tissue perfusion in trained and untrained persons of different ages. Materials and methods: Microcirculation was studied using two methods: biomicroscopy of the nail bed and laser Doppler imaging (EasyLDI, Switzerland). Results: At rest, in the group of trained 20-30-year-old individuals, the average diameter of the capillaries was 20% larger, and the average value of microvascular perfusion was 19% less than in the untrained subjects. After physical activity in both groups there was a significant 5-7% increase in the number of functioning capillaries. The average diameter of the capillaries in the group of trained individuals did not change, and in the untrained group it increased by 14%. Microvascular perfusion in the group of trained individuals increased by 86%, and in untrained subjects by 49%. At rest, the average diameter of the capillaries was 13% in the trained persons of the older age group of 50-60 years, and the average value of microvascular perfusion was 24% higher than in the untrained subjects. After physical exertion, the subjects of both groups had a reliable and comparable increase in the number of functioning capillaries by 11-15%. The average diameter of the capillaries in the group of trained individuals did not change, and in the untrained group it increased by 6%. Microvascular perfusion in the group of trained individuals increased by 65%, and in untrained subjects by 39%. Conclusion: It was found that the physical load caused similar changes in the parameters of microcirculation in persons of different ages. At the same time, the higher aerobic potential of the organism (the value of maximum oxygen consumption) was combined with a large reserve of adaptation of microcirculation, revealed during intensive muscular work. Age differences were manifested by a smaller increase in microvascular perfusion in response to physical exertion in older age groups.