In the traditional eastern health sciences, such as Ayurvedic, and in yoga philosophy, all living things function thanks to the life energy known as prana, which circulates in the body through the subtle pathways known as nadis. Prana can circulate only when the nadis are clear and strong. When the nadi system is blocked, prana cannot flow, and a person's physical and mental health are negatively affected.
The three main nadis are:
- Ida nadi – Called the left channel, ida nadi starts in the muladhara (root) chakra, flowing to the left and weaving in and out of the chakras before ending in the left nostril. This nadi represents mental energy.
- Pingala nadi – Referred to as the right channel, pingala nadi also starts in the root chakra, but flows to the right, weaving in and out of the chakras in a mirror image of ida nadi and ending in the right nostril. Pingala nadi is the origin of prana.
- Sushumna nadi – The central channel, sushumna nadi runs straight up the spine and through the chakras from just below the root chakra to the sahasrara (crown) chakra. This is the nadi of spiritual awareness.
A major focus of Hatha yoga is balancing the nadis, and one of the most effective methods of doing so is a form of pranayama called nadi shodhana, or alternate nostril breathing. It is often included at the end of an asana practice.
The nadis can be compared to the meridians of Chinese acupuncture.