Laser Doppler flowmetry in the diagnostics of tissue microcirculation in track-and-field athletes

Aim. The article deals with establishing functional peculiarities of tissue microcirculation in athletes during the different stages of the training cycle. Materials and methods. We examined 10 track-and-field athletes aged 19-22 (middle- and long-distance running) involved in aerobic trainings. All athletes possess the rank of Candidate for Master of Sport and the average training experience of 8 years. We studied tissue microhemodynamics with the help of laser doppler flowmetry using LAKK-01 (Lazma, Russia) laser analyzer of blood microcirculation. Results. At the preparatory period, we registered a low level of perfusion (3.38 ± 0.21 p.u.) and shunt blood flow (1.27 ± 0.08) and a high level of reserve capillary blood flow (525 ± 55 %) in comparison with the control group. At the beginning of the competitive period, we revealed a significant increase in perfusion (by 81 %) and a decrease in reserve blood flow (by 32 %) and neurogenic (by 16.7 %) and myogenic (by 15.4 %) tone of microvessels in comparison with the preparatory period. Prolonged competitive activities contributed to the increase in neurogenic (by 21.3 %) and myogenic (by 38.4 %) tone, shunt blood flow and T1/2 (by 22 seconds on the average). Conclusions. We established that regular physical loads result in a decrease in the number of functionally active capillaries at rest. The main blood flow passes through nutritive capillaries. At the beginning of the competitive activity, there is an increase in perfusion. As loads increase during the competitive period, microvessel stiffness increases. This contributes to a decrease of their sensitivity to vasodilating factors.