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The changes in baroreflex activity during exercises with different intensities estimated by phase synchronization of blood pressure and heart rateтезисы доклада Тезисы
- Авторы: Anatoly Borovik, Olga Tarasova, Evgenia Orlova, Olga Vinogradova
- Сборник: Biological oscillations and health. Abstracts of the contributions to the 10th European Study Group for Cardiovascular Oscillations (ESGCO) conference
- Тезисы
- Год издания: 2018
- Место издания: Human Research Institute Austria
- Первая страница: 71
- Последняя страница: 71
- Аннотация: Objectives: It is well-known that physical exercise modifies baroreflex cardiovascular control. However, the effect of exercise intensity on baroreflex activity and the dynamics of the transient processes in baroreflex control are poorly understood. The aim of this study was to explore the intensity-dependence and dynamic characteristics of baroreflex activity changes associated with exercise. Methods: Arterial pressure (AP) and ECG were continuously recorded in young healthy men, then phase synchronization index (PSI) was calculated off-line. Before the experiments, the volunteers performed ramp cycling test, to determine the power corresponding to aerobic-anaerobic transition (AAT). To study the influence of exercise intensity, three 15-min-long recordings were obtained at rest and then during light (60% AAT) and heavy (80% AAT) exercise for 9 subjects. The dynamics of baroreflex activity changes was studied for 8 subjects that performed the cycling work with sine-like intensity modulation (mean value 50% AAT, amplitude 30% AAT, frequency from 1 to 10 mHz), PSI were then calculated in successive 4-min episodes. Results: The peak PSI value in the frequency range of baroreflex waves (near 0.1 Hz) tended to be lower at light exercise (0.15±0.04) and was significantly reduced by heavy exercise (0.11±0.04) compared to the rest PSI value (0.19±0.07). The experiments with sine-like intensity pattern showed that PSI changes with alternating power are rather slow – PSI modulation disappeared at 2 mHz, whereas AP and HR modulations were clearly seen at this frequency and higher. Conclusion: The increase of muscle mechano- and hemoreceptors activities during exercise mask the effects of baroreflex modulation of nerve traffic to the heart and decrease the phase synchronization of AP and HR, the effect is enhanced by a rise of exercise intensity. Exercise intensity-induced PSI changes develop slowly, during several tens of seconds. Supported by RFBR (N17-04-01943).
- Добавил в систему: Тарасова Ольга Сергеевна