Abstract
The purpose of this study is to examine dynamic response of cardiac autonomic nervous system activity when breathing frequency continuously modulates raising and lowering. Sixteen healthy young male subjects are participated. The subjects are asked to control their own breathing frequency on fitting the rhythms with a metronome on PC from 3 to 30 times/min. Total duration of varied breathing frequency trials are performed for 5, 10, 20 minutes severally. Before and after the varied breathing frequency trials, voluntary breathing state trial for 5 minutes are recorded successively. The protocolos and procedures in this study have been appriciated by Osaka Electro-Communication University Ethical Committee. Before analysing, the subjects are classified into two groups: habitual exercised (HE) group and non-habitual exercised (NE) group. In our results, nearly 30 times/min breathing state clearly shows the difference of response of heart rate in 10, 20min trials but 5min trial are not different: heart rate of HE group do not change so much although that of NE group have the tendency to be increased. This fact indicates that habitual exercises fairly contribute to the function of cariac autonomic nervous system activity.
