Abstract des Autors

The sympathoadrenergic nervous system is involved in regulating the cardiovascular response to exercise. The purpose of the present study was to investigate the relationship between sympathoadrenergic and hemodynamic responses to exhaustive acute exercise. For this aim plasma norepinephrine (NE) and epinephrine (E), systolic (SBP) and diastolic blood pressure (DBP), and heart rate (HR) were measured in 23 healthy male athletes. The subjects were examined before and 1 min after an exhaustive acute exercise on cycle ergometer. Plasma <NE> and <E>, NE/E ratio, SBP and HR levels significantly increased in response to exercise, while no change in DBP was found. A significant relationship was found between pre- und 1 min post-exercise E values, but not for NE. Both <NE> and <E> per cent variations were correlated positively with SBP and, negatively, with DBP per cent changes. No relationship was observed between <NE> and <E> per cent variations and HR per cent changes. Results form the present study show that cardiovascular response to exhaustive acute exercise is associated with an increased sympathoadrenergic activity. The strong links observed between catecholamines and blood pressure may be an expression of the adaptation mechanism to exercise. The lack of association between catecholamines and heart rate may be attributed to the prompt restoration of vagal tone immediately after exercise and to increased sympathetic nervous activity even after the exercise is over. Verf.-Referat