Cardiovascular function and muscle blood flow during incremental stepwise exercise

The objective of this study was to find out the influence of external factors (training) on relation in changes of cardiac indices and peripheral blood flow during the incremental endurance and sprint exercise test. Two exercise test protocols (during every 1 minute, and second, during every 6 minutes incremental stepwise exercise on an ergocycle) were used for the evaluation of central and peripheral reactions of the cardiovascular system. Arterial blood pressure, stroke volume, cardiac output and arterial blood flow in the calf muscle were assessed. The obtained results show that the values and velocity of changes in indices of cardiovascular function differ depending on the protocol of incremental exercise. They also reflect the functional state of the organism and the whole complex and specificity of acute and chronic adaptation. Synchronous registration of changes in muscle blood flow and the indices of heart function give the possibility to assess precisely the reactions of muscle blood flow and understand the physiological expediency of these changes. We conclude that external factors, i.e. long-term adaptation to sprint or endurance training modifies the ratio between the central and peripheral reactions of the cardiovascular system. It seems that the differences in the heterogeneity of various regulatory mechanisms of cardiovascular reactions depend on the chosen exercise protocol, and belong to endogenous factors.