Savasana translates in English to corpse pose and is the yogic pose of relaxation. It should be practiced just after the Asana or Pranayama or any other physical work.
This pose rests and relieves any, which may have formed in the body and mind.
The period of relaxation should be practiced until the practitioner can feel that his heartbeat and breath have returned to normal and all tension has vanished.
The relaxation in savansana after a yoga practice allows the parasympathetic nervous system to operate, reversing the effects of arousal and returning the body to a balanced state.