Pranayama

Different pranayama techniques, such as Nadi Shodhana, Bhastrika, and Ujjayi, are traditionally said to produce distinct effects, from calming to energizing. Modern research on heart rate variability and the autonomic nervous system has begun to document measurable physiological effects of several of these techniques, though most classical claims remain traditional rather than clinically proven.

Classical texts describe four stages within each pranayama round: puraka, inhalation; antara kumbhaka, retention after inhale; rechaka, exhalation; and bahya kumbhaka, retention after exhale, with named techniques such as Nadi Shodhana, Kapalabhati and Bhramari emphasizing different combinations and ratios of these stages. Contemporary research has measured genuine, technique-specific effects on heart rate variability, blood pressure and stress markers, which is why treating pranayama as one catch-all term can be misleading, since a calming technique and a stimulating one can sit under the same broad word.