Features of Adaptation of Cardiohemodynamics Indices of Medical Students to Physical Exertion

The research is aimed at the study of the cardiovascular parameters of medical students with different features of the central processes such as excitation and inhibition during the physical exertion. The research involved 159 students of the 2nd year of KhNMU including 64 young men and 92 young women. Physical exertion was created by ergometer. The following parameters of cardiovascular system have been studied such as pulse rate, blood pressure (systolic, diastolic, pulse and mean) before physical exertion (rest state), after exertion and during recovery period. To measure and assess the ratio of cortical excitatory and inhibitory processes in the examined people the method of the duration of individual minutes was used. It has been found that in a state of physiological rest male students had higher values of systolic, pulse and mean arterial pressure than young women, although the value of heart rate in these groups had no significant differences. However after physical activity in both groups of examined people a significant increase in heart rate and other hemodynamic indices has been defined, at the same time the change in diastolic arterial pressure was not detected. The obtained results could be explained by predominance of sympathetic division of autonomic cardiovascular center. The difference in duration of individual minute in both examined groups including young women and men has not been detected neither in state of the rest nor after physical exertion. Thus, unidirectional changes in both examined groups of people have not allowed detecting peculiarities of adaptation in this condition. In same time, it is known fact that the balance of central mechanisms such as inhibition and excitation provides features of individual development of adaptation to various stress situations. Following to this fact the examined people have been separated into 3 groups including well-balanced, excitable and inhibitory ones. Among young men the most numerous groups have been well-balanced and excitable but in case of young women the inhibitory group has been predominant. After physical exertion in examined people the unidirectional changes of heart rate and hemodynamic indices have been defined. In same time these changes varied in degree of gender and features of balance of central processes such as excitation and inhibition. Thereby, the significant influence of the balance of central excitation and inhibition in case of forming of the complex adaptive functional changes during physical exertion has been found. The obtained results have shown that among indices of nonspecific adaption to emotional and physical exertion the index of the duration of individual minute is the most informative. The research demonstrated that activity of peripheral link of autonomic regulation in significant degree depends on the balance of central processes thus in absence of considerable varieties of examined indexes in state of rest however their qualitative characteristic at physical exertion have shown certain connection with the balance of central processes. The physical exertion is accompanied by chronic emotional studying stress which allowed detecting the features of adaptive reactions where heart rate, systolic and diastolic blood pressure were the most sensitive parameters of hemodynamics.