Classical yogic texts such as the Yoga Chudamani Upanishad and Yajnavalkya Samhita explain that there are 72,000 nadis (bioplasmic pathways) in the human pranic framework. Other texts say that there are more; actually the exact number is unimportant. These nadis act as the controlling medium and base for the physical body. Pranic flows have recently been photographed with Kirlian photography and the profound functions of the pranic body are slowly becoming obvious to modern science.
Yoga nidra helps to harmonize the pranic flows throughout the whole human structure. This is especially true during the stage of rotating awareness through the different parts of the body. It is the mind that controls prana, and mere mental awareness of a specific part of the body induces How of prana to that area. Rotation of awareness through the different parts of the body systematically induces a flow of prana to each part in turn. This leads to harmonization and awakening of the pranic flows in the entire human framework. This factor alone helps to eliminate or relieve ailments and improve health. It improves the vitality of the whole body since this is dependent on a smooth flow of prana. The practice of yoga nidra has deep implications.
Yoga nidra can be called ‘yogic acupuncture’. Because of its profound influence on the pranic currents of the body it is a good preliminary practice for attaining mastery of prana (prana vidya).