Summary & Conclusion: This study observed the nostril dominance in school students (13-17years) who were attending a residential Yoga camp. The randomly allocated groups practiced three different Yoga modules in the same setting. Results showed that at base line significantly larger number of students had right nostril dominance at sunrise and left nostril dominance at sunset. More boys had right nostril dominance at sunrise & left nostril dominance at sunset & more girls had left nostril dominance at sunrise & right nostril dominance at sunset.
After 8 days of Yoga practices at sunrise right nostril dominance reduced & both nostrils increased. At sunset left nostril dominance reduced & both nostrils dominance increased. At sunrise higher number of girls shifted to both than boys. At sunset there was no significant change in both sexes.
Comparison between groups showed similar trends with highest number of students shifting towards both nostrils in creativity group at sunrise and in IQ group at sunset.
Earlier studies on uni-nostril breathing Pranayama have brought out valuable observations. Right nostril breathing Pranayama increased O2 consumption and sympathetic activation. Left nostril breathing decreased sympathetic arousal (9&10). In the present study of naturally occurring nostril dominance at baseline it is seen that at sunrise boys tend to be highly active as indicated by right nostril dominance & as the day falls the restful evening is indicated by left nostril dominance.
Svara Yoga (Shiva P126) states that left channel (Ida or candra or moon Nadi) is controlled by the feminine power 'sakti' and right channel (Pingala or Surya or sun) by 'Siva' masculine power. This baseline observation that more boys had right nostril dominance and more girls had left nostril dominance at sunrise is in consonance with scriptural proclamation. The observations of reversed nostril dominance in boys and girls at sunset are also in tune with the same text.
Further, the baseline nostril dominance observed in the students of the present study is lower (40%) than patients (15) with chronic pain (70%) or normal (14) adults (50%). Also both nostrils were much lower in chronic patients (6%) as compared to adults (15%) or students (26%).
The scriptures describe that Yoga is to get balance at all levels. So, we can expect that with Yoga practices, the uni- nostril dominance would reduce and shift towards equal flow in both nostrils. The results of the study are indicative of this balance. Further the shift in nostril dominance after Yoga practices showed that increase in both nostrils was highest in students (41%) as compared to 19 % in adults and 10% in Chronic pain patients (14, 15).
Looking at the comparison of changes between the three groups, who practiced specific IAYM, for PS, IQ & CR, it is observed that maximum shifts towards both nostrils (from 23 to 52%) at sunrise were in Creativity group and at sunset (from 22 to 54%) was in IQ group. This is because, the CR yoga module comprised of practice of left nostril breathing (Candra Anuloma Viloma) pranayama and the IQ yoga module had the practice of right nostril breathing (Surya Anuloma Viloma) Pranayamas done 27 rounds 4 times a day. Hence this would have balanced the nostril flow.
Observing the daily changes (Figs 2, 3) at sunrise, the first three days have shown no significant changes in nostril dominance. Yoga appears to start showing its effect from 4th day at sunrise and 6th at sunset with continuing improvements until the last day. This may be indicative of the scriptural claim that yoga is more effective in the morning and should be practiced in the Brahmi Mahurta (starting earlier to sunrise). Further, the demonstrable benefits of yoga within a short period of 4 to 6 days observed in this study is contrary to the normal notion that yoga is a slow process and takes a long time to show its efficacy.