Тип публикации: статья из журнала
Год издания: 2009
Идентификатор DOI: 10.1007/s11055-009-9168-9
Ключевые слова: Autoregulation, Cerebral hemodynamics, Physical exercise, adult, arterial pressure, article, bicycle ergometry, blood flow velocity, brain blood flow, brain vascular resistance, controlled study, Doppler echography, exercise, hemodynamics, human, human experiment, male, middle cerebral artery, normal human, regulatory mechanism, systole, Cerebrovascular Circulation, Coronary Circulation, Humans
Аннотация: Cerebral hemodynamic reactions to light physical exercise increasing stepwise on a bicycle ergometer were studied in healthy young male subjects. Hemodynamic parameters were measured by transcranial Doppler ultrasonography from the middle cerebral artery (MCA) before the start of the study and during the last few seconds of each exПоказать полностьюercise step. Cerebral hemodynamic reactions to physical exercise were characterized by a significant increase in systolic blood flow rate in the middle cerebral artery only at exercise levels of about 0.25 W/kg body weight (90 rpm at 0 W/kg) with no further increase in the blood flow rate with increases in loading to 0.5 W/kg body weight. The mechanism stabilizing blood flow rate in the cerebral arteries as physical exercise increased and, thus, the mechanism of cerebral circulatory autoregulation consisted of a arterial pressure-dependent increase in regional cerebral vascular resistance. The threshold at which the cerebral blood flow rate autoregulatory mechanism was triggered in normal subjects corresponded to a loading of about 0.25 W/kg and a systolic arterial pressure of about 140-145 mmHg. © 2009 Springer Science+Business Media, Inc.
Журнал: Neuroscience and Behavioral Physiology
Выпуск журнала: Vol. 39, Is. 6
Номера страниц: 581-586