Abstract
Backgrounds: The APG system indicates heart rate variability, by using the coefficient of the variation of the a-a intervals (CVaa%), and also indicates the power rate in the low frequency area and the high frequency area that was derived from frequency analysis (LF/HF) . Purposes: The purposes of this study are to make clear the relationship between CVaa% and LF/HF, to know the standard range of LF/HF in the calm state and in the ordinary state, and to know whether there is a circadian rhythm in the parameter of the frequency analysis. Objectives and method: We recorded APG of one healthy girl of 21 y.o. immediately after waking up in the morning during 62 days. We recorded APG of the 193 healthy (ages 30-59) before exercise and after exercise in the afternoon. Statistical analyses : 1) We indicated the mean of CVaa%, LF, HF, total Power, LF%, HF% and LF/HF immediately after waking up in the morning. We examined the correlation between body temperature and each parameter, and observed the circadian rhythm of each parameter. 2) We analyzed the influence of age and exercise on each parameter. Results: 1) The mean LF/HF in the calm state in the morning was 1.4 (SD=0.9) . The total power, HF and LF had significant negative correlation to body temperature, and showed a circadian rhythm of biphasic. 2) As to 193 men, there was no significant difference among age categories in LF, HF, the total power, HF% and LF% both before and after exercise. There was no significant difference among age categories in LF/HF before exercise, but LF/HF after exercise in the old people was significantly less than in the young people. After exercise, there was not significant change in the total power. While, the HF and HF % significantly decreased and LF % and LF/HF significantly increased after exercise. The 95% confidence interval of the LF/HF before exercise was 2.0-2.6, and that of LF/HF after exercise was 4.3-5.8. The CVaa% had significantly positive correlations to total power, LF and HF, but did not have any correlation to LF%, HF% and LF/HF Conclusion: 1) It can be said that the LF/HF in the calm state is<2.0, the LF/HF in the ordinary state indicates 2-3, and the LF/HF in the condition which it gets excited at is>4.0.2) The CVaa % may reflect the activity of autonomic nerve function, but not reflect the balance of autonomic nerve function. 3) The autonomic nerve function of a young woman has a circadian rhythm of biphasic.
