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The cardiovascular system is one of the most important functional systems of the body, which determine the level of physical performance of the body. Insufficient study of the response of the circulatory system to the combination of strength training with endurance exercises requires more detailed comparative studies of the impact of dynamic and static loads on the indicators of central hemodynamics. Accordingly, the aim of our study was to study the characteristics of the reaction of the cardiovascular system in the period of early recovery after dosed exercise of a dynamic and static nature. The study examined the response of the central hemodynamics of young men in the period of early recovery after dynamic loading (Martine functional test) and static loading (holding on the stand dynamometer DS-200 force with a power of 50% of maximum standing force). The change in circulatory system parameters was recorded using a tetrapolar thoracic impedance rheoplethysmogram on a computerized diagnostic complex “Cardio +”. It is established that the dynamic load in the period of early recovery does not cause a significant positive chronotropic effect, leads to a decrease in vascular resistance of blood flow, to an increase in pulse blood pressure. The increase in cardiac output is mainly due to the increase in stroke volume, which indicates a fairly high functional reserves of the heart. It is revealed that under conditions of static loading the reaction of central hemodynamics and the course of early recovery are radically different from the changes of indicators under dynamic loading. In persons with a normodynamic type of reaction to dynamic load, there are no significant changes in the minute volume of blood at a similar volume of active muscle mass static load. Meeting the metabolic needs of working skeletal muscles and compensating for the oxygen debt is realized by increasing the total peripheral vascular resistance and increasing systolic blood pressure in the postpartum period. The physiological meaning of this phenomenon is to maintain a sufficient level of venous return of blood to ensure the pumping function of the heart.

We studied the changes in central hemodynamics in the early recovery period after physical load in 28 young men. Dynamic loading was induced using a modified Martine functional test, static loading - by maintaining on the standing dynamometer DS-200 muscle effort in the amount of 50% of maximum standing force. The change in central hemodynamic para- meters was recorded by tetrapolar thoracic impedance rheo- plethysmogram using a computerized diagnostic complex «Cardio +». Dynamic exercise during early recovery did not lead to a significant increase in heart rate, however, it caused a decrease in the resistance of resistive blood vessels and an increase in pulse blood pressure. The increase in minute blood volume in our study is mainly due to an increase in stroke volume, pointing for high functional reserves of the heart. In the case of static physical activity, the adaptive reactions of central hemodynamics and the course of the processes of early recovery of the circulatory system are radically different from similar indicators during dynamic physical activity. In subjects with a normodynamic type of response of the cardiovascular system to dynamic load, no significant changes in the minute volume of blood flow were registered at a similar volume of active muscle mass static load. In subjects with a normodynamic type of cardiovascular response to dynamic load, no significant changes in cardiac output were observed at a similar static load in terms of active muscle mass. However, during early recovery period, the total peripheral vascular resistance and systolic arterial pressure were increased. The increase in total peripheral resistance may be due to reactive hyperemia in ischemic skeletal muscle caused by increased blood flow to the capillaries after muscle relaxation and delayed outflow into the veins. The significant increase in systolic blood pressure can be explained by the mechanical obstruction of blood flow in the muscle capillaries during prolonged static contraction.