Evaluation of the Effect of Left Nostril Breathing on Cardiorespiratory Parameters and Reaction Time in Young Healthy Individuals

Background: Pranayama, a yogic breathing practice, produces several physiological responses in healthy individuals. Hypertension is a critical and booming public health challenge all over the world. Yoga is one of the effective methods to reduce blood pressure (BP) and pulse rate (PR). Objective: To evaluate the effect of left nostril breathing (LNB) exercise on cardiorespiratory parameters and reaction time (RT) in young healthy individuals. Materials and methods: In this study, 106 young healthy individuals between 18 and 25 years of age were included. The systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse rate (PR), respiratory rate (RR), vital capacity (VC), peak expiratory flow rate (PEFR), and reaction time (RT) of volunteers were recorded at baseline (before exercise) and after two weeks of left nostril breathing exercise performed 45 minutes daily. Results: There was a significant reduction in SBP (126.64 +/- 15.51 mmHg versus 116.29 +/- 11.91 mmHg; Cohen's d (effect size): 0.87; p < 0.0001)), DBP (76.57 +/- 14.87 mmHg versus 71.07 +/- 11.39 mmHg; Cohen's d: 0.48; p < 0.0001), PR (85.32 +/- 15.44/minute versus 81.77 +/- 13.02/minute; Cohen's d: 0.27; p < 0.0001), and RR (14.26 +/- 2.15/minute to 13.17 +/- 2.03/minute; Cohen's d: 0.54; p < 0.0001). A significant increase was observed in VC (3.42 +/- 0.62 versus 3.67 +/- 0.65; Cohen's d: 0.39; p < 0.0001) and PEFR (467.81 +/- 46.66 versus 498.29 +/- 51.50; Cohen's d: 0.59; p < 0.0001). There was a significant decrement in auditory reaction time (ART) (164.36 +/- 27.20 ms versus 143.84 +/- 20.32 ms; Cohen's d: 0.85; p < 0.0001) and visual reaction time (VRT) (190.25 +/- 31.48 ms versus 163.75 +/- 21.72 ms; Cohen's d: 0.98; p < 0.0001). There was no significant change in maximum heart rate (MHR) after cardiorespiratory activity (CRA) (p > 0.434). Conclusion: Left nostril breathing is associated with a decrease in cardiovascular parameters and an increase in VC and PEFR. This technique may be useful for putting up a fight against the stress and strain of daily life. This simple exercise may also be a beneficial adjuvant to pharmacological therapy in hypertensive patients.