title: Effect of Different Pranayamas on Respiratory Sinus Arrhythmia.
abstract: BACKGROUND
  Respiratory Sinus Arrhythmia (RSA) is the differential change of Heart Rate (HR) in response to inspiration and expiration. This is a noninvasive sensitive index of parasympathetic cardiac control.
  
  
  OBJECTIVE
  To evaluate changes in RSA by utilizing a simple and cost-effective analysis of electrocardiographic (ECG) tracings obtained during performance of four pranayama techniques.
  
  
  METHODS
  Fifty two trained volunteers performed the following pranayamas with different ratios for inspiration and expiration: sukha (1:1), traditional (1:2), pranava (1:3) and savitri (2:1:2:1) and ECG was recorded while performing the techniques with rest period of 5 minutes in-between. HR was calculated and maximum HR during inspiration (Imax), minimum HR during expiration (Emin), differences between Imax and Emin (Δ), percentage differences between I(max) and Emin (Δ%) and expiration: inspiration ratio (E:I) calculated by respective formulae. Statistical analysis was carried out using repeated measures of ANOVA with Tukey-Kramer multiple comparisons test.
  
  
  RESULTS
  There were significant differences between groups in all five aspects namely: p= 0.0093 for mean Imax, p = 0.0009 for mean Emin, and p < 0.0001 for Δ HR (I-E), Δ% HR (I-E) and E:I ratio. Pranava pranayama produced the greatest changes in all five comparisons.
  
  
  CONCLUSIONS
  We suggest that further short and long term studies be undertaken with pranava pranayama in patients to further qualitatively and quantitatively evaluate inherent mechanisms of this simple technique. Addition of these cost-effective techniques to the medical armory will help patients of rhythm disorders and other cardiovascular conditions.
authors.affiliation: Deputy Director, Centre for Yoga Therapy, Education and Research (CYTER), Mahatma Gandhi Medical College and Research Institute , Pillayarkuppam, Puducherry, India .
authors.forename: Ananda Balayogi
authors.initials: AB
authors.lastname: Bhavanani
authors.affiliation: Associate Professor, Department of Physiology, Mahatma Gandhi Medical College and Research Institute , Pillayarkuppam, Puducherry, India .
authors.forename: Jeneth Berlin
authors.initials: JB
authors.lastname: Raj
authors.affiliation: Co-ordinator and Yoga Therapist, CYTER, Mahatma Gandhi Medical College and Research Institute , Pillayarkuppam, Puducherry, India .
authors.forename: Meena
authors.initials: M
authors.lastname: Ramanathan
authors.affiliation: Professor and Head, Department of Physiology, and Director CYTER, Mahatma Gandhi Medical College and Research Institute , Pillayarkuppam, Puducherry, India .
authors.forename: Madanmohan
authors.initials: M
authors.lastname: Trakroo
keywords: Cardiovascular; ECG; Heart rate; Yoga