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Heart rate variability Analyses using wearable sensing system in response to parabolic flight (LB799)

New concept as wearable heart rate and gravity sensing system requires the development of bio‐signal acquisition device to be easily integrated into the health management in space, microgravity and hypergravity. The purpose of this study is to examine the acute effects of microgravity and hypergravity on the frequency domain analysis of heart rate variability (HRV) with the new wearable sensing system for electrocardiogram and gravity acquisition during parabolic flight. Six healthy volunteers underwent a series of experiments in sitting position involving parabolic flight. In this study, a new wearable sensing system “Mybeat” (Union Tool, Co., Tokyo) for Electrocardiogram and gravity acquisition was used. The ratio of low frequency to high frequency (LF/HF) components of HRV in the hypergravity phase before microgravity during parabolic flight was higher than that in horizontal before parabolic flight. In microgravity, the LF/HF components of HRV decreased. In contrast, there were no differences in the HF components of HRV between different gravity phases during parabolic flight. These results suggest that the acute effect of the different gravity phases on autonomic nervous activity might be affected by the modulating the dominance between sympathetic and parasympathetic nervous activity. In addition, the system could simultaneously provide information about the gravity and HRV in different gravity phases during parabolic flight. Supported by Grants‐in‐Aid for Science Research from the Japanese Ministry of Education, Culture, Sports, Science and Technology.