Effect of left nostril breathing on postexercise recovery time

Background: The nasal cycle is the alternating congestion and decongestion of the nostrils during normal breathing, marking the shift between the sympathetic and parasympathetic systems, the latter being prominent when breathing through the left nostril. The post-exercise period is characterized by a gradual shift from sympathetic to parasympathetic dominance. It is hypothesized that breathing only through the left nostril will aid in accelerating this shift in the postexercise period. Objectives: The objective of this study is to assess the effect of left nostril breathing on post-exercise recovery times of heart rate and blood pressure (BP). Materials and Methods: A total of 60 young healthy male volunteers were instructed to walk on a flat treadmill, following a fixed protocol. Heart rate and BP were measured at rest and postexercise they were monitored every minute until they reached the baseline. The recovery time was noted. The procedure was the same on the 3rd day, except that during the postexercise period, the participants were instructed to breathe only through their left nostrils. Results: The recovery times of heart rate and BP, when breathing through the left nostril only, was significantly lower than when breathing normally. Conclusion: The left nostril breathing technique lowered the postexercise recovery times of cardiovascular parameters, which can be attributed to improved parasympathetic tone. These findings on the post-exercise state may be extrapolated to pathological states of sympathetic dominance, and left nostril breathing can be used as an adjunct to pharmacological therapy to manage such conditions.