Effect of relaxation training on cardiac parasympathetic tone

Authors

  • MASAHITO SAKAKIBARA,

    1. Department of Psychology. Aichi Gakuin University, Japan
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    • Address reprint requests to: Masahito Sakakibara, M. A., Division of Clinical Psychology, Tokai Central Hospital, Sohara, Kakamigaharacity, Gifu-prefecture 504, Japan.

  • SATOSHI TAKEUCHI,

    1. Third Department of Internal Medicine, Nagoya City University Medical School, Japan
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  • JUNICHIRO HAYANO

    1. Third Department of Internal Medicine, Nagoya City University Medical School, Japan
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  • This work was supported in part by a Grant-in-Aid for Scientific Researches No. 02951044, from the Japanese Ministry of Education, Science and Culture to M. Sakakibara.

Abstract

To examine the hypothesis that the relaxation response is associated with an increase in cardiac parasympathetic tone, the frequency components of heart rate variability during relaxation training were investigated in 16 college students. Electrocardiograms and pneumograms were recorded during a 5-min baseline period followed by three successive 5-min sessions of the autogenic training (relaxation) or by the same periods of quiet rest (control), while subjects breathed synchronously with a visual pacemaker (0.25 Hz). Although neither the magnitude nor the frequeney of respiration showed a significant difference between relaxation and control, the amplitude of the high-frequency component of heart rate variability increased only during relaxation (p= .008). There was no significant difference in the ratio of the low-frequency (0.04–0.15 Hz) to the high-frequency amplitudes. The increased high-frequency amplitude without changes in the respiratory parameters indicates enhanced cardiac parasympathetic tone. Thus, our results support the initial hypothesis of this study. Enhanced cardiac parasympathetic tone may explain an important mechanism underlying the beneficial effect of the relaxation response.

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