[Analysis of correlation between physical training and autonomic function by using multivariate analysis:...

The purpose of this study is to assess the effects of physical training on autonomic nervous function. Twenty-two healthy subjects(12 males and 10 females) participated in this study. We inquired contents of the exercise for each subject. Continuous ECG was recorded during 320 seconds at supine resting. Respiratory rhythm was fixed at 0.25 Hz(15 time/min). On the basis of spectral analysis of heart rate variability, the autonomic nervous function was assessed by low frequency power(LF: 0.06-0.13 Hz) and high frequency power(HF: 0.16-0.50 Hz). The predominance of sympathetic nervous activity were indicated by the LF/HF and LF-HF. Relationship between physical training and autonomic function was analyzed by using multivariate analysis(partial correlation analysis). As the results, LF power and LF-HF negatively correlated with training time per day, energy expenditure per day, energy expenditure per week, and total energy expenditure, respectively(p < 0.05). HF power positively correlated with energy expenditure per day, energy expenditure per week, and total energy expenditure, respectively(p < 0.05). These results indicate not training time but energy expenditure alters the autonomic nervous function. This index may be useful for evaluating training effect on the promotion of health.