Effects of Qi-therapy (external Qigong) on cardiac autonomic tone: a randomized placebo controlled study

Heart-rate variability (HRV) was compared in 40 subjects receiving external Qi-therapy (QT) or placebo control therapy, in a randomized placebo controlled design experiment. There were significant time, and group x time interactions in heart rate (HR), low frequency (LF), high frequency (HF), and LF/HF. These suggest that QT reduced the HR and increased HRV as indicated by a reduced LF/HF power ratio of HRV. These findings suggest that QT stabilizes the sympathovagal function more than placebo therapy.