Abstract:
AIM AIM To observe the effects of vestibular stimulation by head movement on cardio vascular functions during short-arm centrifugation.
METHODS Twelve men and twelve women subjects were exposed to short-arm centrifuge of 2 Gz at feet level for 8 minutes, with head still and intermittent head-turns continuously. Heart rate, b1ood pressure and heart rate variability (HRV) were measured and vestibular function was evaluated during the exposure.
RESULTS Compared with those pre-exposure, the heart rate, diastolic pressure, low frequency of HRV and ratio of low frequency to high frequency (LF/HF) decreased significantly in subjects with head-turns during short-arm centrifugation. When the subjects were exposed to short-arm centrifugation, the rate of LF/HF change of women was significantly higher than men. The LH/HF significantly increased in men with head-turns compared with those in the subjects with the head sti1l during short-arm centrifugation.
CONCLUSION The exposure of short-arm centrifuge significantly enhances the sympathetic excitability in male and female subjects. Compared with men, women may be more sensitive to centrifuge exposure and more likely to have changes in autonomic nervous function.