Зміни центральної гемодинаміки у період раннього відновлення після різних режимів фізичного навантаження

Abstract

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.