The Ida Nadi commences it’s ascend in the human body from the Root or the Muladhara Chakra and climbs from the left side of the Merudanda [Spinal Column in the English language]. It wraps the other Chakras, reaches the Ajna or the Third Eye Chakra, and then reaches the base of the left nostril.
The Ida Nadi is ruled by Chandra [Moon] and it nature is considered feminine. If the breathing is primarily, through this Nadi then it increases the Sheetalta or Coolness in the body as the Ida Nadi is also known as the Sheetal Nadi.
The Pingala Nadi also known as the Surya Nadi is considered Male in nature and if the breathing is primarily through the Pingala Nadi, it increases the warmth in the body. Like the Ida Nadi, the Pingala Nadi also commences it’s ascend through the Muladhara Chakra and climbs from the right side of the Merudanda, and wraps the other Chakras and reaches the Ajna Chakra and then ends at the root of the right nostril.
The Pingala Nadi is responsible for increasing the Jatharagni or digestive fire in the body, which enhances the smooth functioning of the digestive organs and increases the appetite. This is the reason why Yoga prescribes Vamkukshi or lying or sleeping on the left side after meals as this enhances the functioning of the Pingala Nadi and the food is easily digested and the Udar Vayu or the Abdominal Gas does not put pressure on the heart.