from the left of it and the pingala starting from the right of it. The ida and pingala then intertwine the shushumna crossing over at each chakra point up to when they reach the Third Eye Chakra in the center of the brain. Here all three nadis end.
The ida nadi is the ying energy of the body. It is responsible for cooling, passive, meditative, feminine energy, while the pingala nadi is the yang energy of the body. It is responsible for the hot, active, masculine energy of the body. Normally, one of these channels is more active than the other at any given time of the day and prana is flowing through this more active channel at that time.
The key to opening, healing and balancing the chakras lies in having prana flow through shushumna. This happens when ida and pingala are brought into immaculate balance. Kundalini yoga can be thought of nothing more than a science to activate flow of prana though shushumna. All the famous kundalini yoga sets (kriyas), pranayamas (breathing exercises), mantras and meditations are designed to clear blockages in the nadi system, balance ida and pingala and cause shushumna to flow.
As prana flows through shushumna, it activates each of the chakras, which in turn bestows health to the physical region where that chakra lies. In addition, having the chakras open also bestows emotional and mental balance for the emotions that that particular chakra is responsible for. Once the system is brought to an optimal level, energy (kundalini shakti) can flow freely up and down the central channel and finally up into the crown chakra. This then brings about a transformation of consciousness and the yogi penetrates the veil of separate existence and experiences enlightenment.