RESUMO
Background: Heart rate variability (HRV) can be measured non-invasively in humans to study the physiological responses to various stimuli. The sympathetic branch increases heart rate and the parasympathetic branch decreases heart rate. HRV is an indicator of the dynamic interaction and balance between these two divisions of the Autonomic Nervous System. The pranic healers practice meditation which utilizes unification of body and mind. A reduced HRV is associated with increased risk of cardiac and overall mortality. Studies suggest a number of non-pharmacological techniques for the improvement of HRV. These techniques are believed to stabilize the ANS by modulating the parasympathetic nervous system and in turn improve HRV. The impact of these techniques on HRV and their effectiveness as therapeutic tools in patients with reduced HRV is to be determined.Methods: This study included 15 professional pranic healers as subjects in the age group 18-40 years. ECG was recorded during the phases, Series 1 (before meditation) and Series 3 (during meditation). HRV parameters were computed with the aid of suitable software and were analyzed. Results: The HRV parameters (Mean, Low frequency / LF, High frequency / HF, Total power, pNN50%) were compared. Power spectrum analysis showed distinctive change in frequency components. Low frequency component (LF; 0.04Hz to 0.15Hz), high frequency component (HF; 0.15Hz to 0.40Hz) and total power were significantly higher during the meditation phase (p = 0.05). pNN50% showed a trend towards decrease (though not significant) during the meditation phase (p = 0.066).Conclusions: The variance of the heart rate during meditation was significantly higher during meditation than before meditation for all subjects. These techniques are believed to stabilise the ANS by modulating the parasympathetic nervous system and in turn improve HRV.