Pranayama is the breathing practices that are part of Yoga.
As with yoga, there are different types of pranayama, each has a different effect on the body-mind system. Ayurveda indicates which exercises are suitable for different constitutional types.
Nadi Shodana is also known as alternative nostrils breath, alternating breathing through left and right nostrils will have a direct connection with the brain: left nostrils to the right hemisphere of the brain, right nostrils to the left.
Each person has a nostril dominance, this means that mostly breath through that nostril, however during the day the dominance can change from left to right and vice-versa.
Pranayama is a very complex science, however, Ayurveda gives some guidelines specific to the Doshas.
A person of Pitta constitution should practice left nostril breathing: inhaling through the left nostril and exhaling through the right, using thumb and middle finger to close and open alternate nostrils. This exercise creates a cooling, Pitta balancing effect in the body by enhancing female energy.
A person of kapha constitution should do right nostril breathing, inhaling through the right nostril and exhaling through the left. This exercise stimulates the male energy and creates a heating effect in the body, balancing the cold caracteristics of Kapha.
A person of vata constitution should perform alternate nostril breathing. As vata is an active force, alternate nostril breathing brings balance, balancing female and malke energy, cold and heating energy in the body.