Shavasana, the corpse posture, is always executed at the end of dynamic Yoga practice and is considered the most significant Asana of the entire session. Why?
Because it is the Asana that is maintained the longest and in silence. What actually happens when we stay in Shavasana?
The physical practice of Asana acts on muscles, as well as on our brains, creating interior space and awakening body heat. Each Asana is a specific posture, which acts by elongating and stretching the muscles that surround the joints, stimulating liquid tissue circulation and nerve communications, improving the health of the back and spine, and balancing and purifying the psychic centers called chakras.
Inversion poses, also called final poses, connect us with the parasympathetic nervous system. Following their execution, we are prepared for a moment of real relaxation, the deep kind, through immobility and silence. We are ready for Shavasana.
In the Shavasana posture, Theta brain waves predominate, with oscillating and vibrating electrical activity at a frequency of 4-8 Hz. This state of brain function awakens the intuitive unconscious mind, allows us to access deep memories, and connects us to the collective unconscious. Healing takes place in this state. The deepest states of Shavasana reach the brain state where Delta waves appear (frequency 0.5 – 2 Hz). This is the brain state of sleep. In Shavasana, the presence of the subtle energetic body (represented in the image below) fluctuating over the physical body, is perceived. For all these reasons, Yoga Nidra is performed in Shavasana.