Analysis of the Effects of Breathing Exercises on Autonomic Activity in Young Women

Abstract

This study aims to analyze the effects of breathing exercises on autonomic nervous system activity. Nine young Japanese women participated in the Day 1 session (relaxation [R]) and the Day 2 session (breathing exercises [BE]). After 2 Day sessions, they performed BE at home, daily for 4 weeks. We held one session per week for 4 weeks. BE included diaphragmatic exercises, which had a longer exhalation phase than inhalation phase. We measured pulse waves from photoplethysmography. They were analyzed for estimating the relative pulse wave amplitude (rPWA) and length (rPWL). The results showed that the rPWL after 5 minutes of BE was significantly higher than those at the end of the BE and the rPWL during BE lower than those before BE. Therefore it was suggested that sympathetic activity was dominant during BE and parasympathetic activity was dominant after BE.