Impact of Fast and Slow Pranayam on Cardio Vascular Autonomic Function among Healthy Young Volunteers: Randomized Controlled Study

Abstract

Background: Pranayama refers to the conscious manipulation of the breath in order to modulate the cosmic energy (prana) from the air in the environment. The techniques of Pranayam include practices that are performed in a slow or fast type. Aim: Investigate and correlate the impact of three months practice of fast and slow pranayam on cardiovascular autonomic function among healthy young volunteer. Materials and Methods: Total of 75 volunteer subjects were randomized into control group (Group1: n=25), fast pranayama group (Group 2: n=25) and slow pranayama group (Group 3: n=25). The pranayam practice (Slow Pranayam Group-Savitri, Pranav and Nadisodhana: Fast Pranayam Group-Bhastrika, Kukkuriya and Kapalabhati, were practiced 30 minutes per day, 3 days per week for 3 months either slow or fast pranayam by a certified yoga teacher. The recording of Short term Heart Rate Variability (HRV) was done at the before and after 3 months of study period. Result: The LF/HF ratio which is the best indicator of Sympathovagal balance was reduced significantly in slow pranayam group showing a shifting of balance towards parasympathetic tone. The RMSSD which is considered to be the best predictor of parasympathetic tone significantly increased in slow pranayam group. A significant increase (HF) nu and decrease (LF) nu was noted in slow and fast pranayam respectively after yoga intervention. Conclusion: Results of our study demonstrates that slow and fast pranayam practices are more effective to maintain sympatho-vagal balance by modulating sympathetic and parasympathetic division of autonomic nervous system.