Enhancement of sleep stability with Tai Chi exercise in chronic heart failure: preliminary findings using an ECG-based spectrogram method

Sleep Med. 2008 Jul;9(5):527-36. doi: 10.1016/j.sleep.2007.06.003. Epub 2007 Aug 3.


Objective: To assess the effects of a 12-week Tai Chi exercise program on sleep using the sleep spectrogram, a method based on a single channel electrocardiogram (ECG)-derived estimation of cardiopulmonary coupling, previously shown to identify stable and unstable sleep states.

Methods: We retrospectively analyzed 24-h continuous ECG data obtained in a clinical trial of Tai Chi exercise in patients with heart failure. Eighteen patients with chronic stable heart failure, left ventricular ejection fraction <or= 40% (mean [+/-standard deviation] age, 59+/-14 years, mean baseline ejection fraction 24%+/-8%, mean) were randomly assigned to receive usual care (N=10), which included pharmacological therapy and dietary and exercise counseling, or 12 weeks of Tai Chi training (N=8) in addition to usual care. Using the ECG-based sleep spectrogram, we compared intervention and control groups by evaluating baseline and 12-week high (stable) and low (unstable) frequency coupling (HFC & LFC, respectively) as a percentage of estimated total sleep time (ETST).

Results: At 12 weeks, those who participated in Tai Chi showed a significant increase in HFC (+0.05+/-0.10 vs. -0.06+/-0.09 % ETST, p=0.04) and significant reduction in LFC (-0.09+/-0.09 vs. +0.13+/-0.13 % ETST, p<0.01), compared to patients in the control group. Correlations were seen between improved sleep stability and better disease-specific quality of life.

Conclusions: Tai Chi exercise may enhance sleep stability in patients with chronic heart failure. This sleep effect may have a beneficial impact on blood pressure, arrhythmogenesis and quality of life.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Chronic Disease
  • Combined Modality Therapy
  • Electrocardiography, Ambulatory*
  • Exercise Test
  • Female
  • Fourier Analysis
  • Heart Failure / psychology
  • Heart Failure / rehabilitation*
  • Heart Rate
  • Humans
  • Male
  • Middle Aged
  • Polysomnography*
  • Quality of Life / psychology
  • Signal Processing, Computer-Assisted*
  • Sleep Deprivation / psychology
  • Sleep Deprivation / rehabilitation*
  • Sleep Initiation and Maintenance Disorders / psychology
  • Sleep Initiation and Maintenance Disorders / rehabilitation*
  • Tai Ji*