The Sanskrit word shava means corpse hence this is the Corpse. The aim of the shava-asana is to make the body and mind perfectly still and relaxed. It will take a little time to perfect it.
Position of Readiness
This is Motionless & fixed but relaxed posture like dead body.
Lie down on your back. Keep the whole body loose and in a straight position. Palms can be either on the floor or you can keep them upwardly. Do not use any pillow under your head. Keep your eyes gently closed with the facial muscles relaxed and breathe deeply and slowly through the nostrils.
Close your eyes and keep them closed for two seconds. Then gently open them for two seconds. Do this simple opening and closing of the eyes for three to four times.
Open the eyes again and look upward, then downward, then straight. Now look towards the left side, then towards the right side, then straight again and then close the eyes. Repeat this eye exercise two to three times.
Now open your mouth wide without straining it. Turn the tongue inside the mouth in such a way that its tip is folded back towards the throat area, then close the mouth. Keep the mouth closed and tongue folded for 10 seconds. Then open the mouth and bring the tongue back to its normal position, then close the mouth. Repeat the process for two to three rounds.
Keeping your eyes closed, bring your mental attention towards your toes. See(mentally) that the toes are relaxed. Then move slowly upward and towards the head area mentally by checking the knees, thighs, waist, spinal cord, back, shoulders, neck, arms, palms, fingers and rest of the areas of the body to be sure that they are actually relaxed. Make a slight movement of the neck and head by turning right and left. Then let the head rest at a comfortable position. Now the entire body is physically relaxed.
Then relax the mind with the following process:
Select a place of natural beauty which you have ever visited and liked, such as, a park, a garden, a lawn or a riverside and feel as if you are mentally present at that place. Attach your mind to that place. Feel as if you are lying at that place and breathing the air of the same environment. Now while keeping the mind involved with that environment, do some deep breathing. In this deep breathing, just exhale and inhaler slowly but deeply. During the breathing, the stomach should go upward while inhaling and it should come forward while exhaling. One exhalation and one inhalation in make one round. Do not rush in this deep breathing. Make about ten lo twelve rounds. When the deep breathing is over, feel as if you are going to sleep. Now relax completely. Stay in that position for five to ten minutes. Then open your eyes and stretch your body and then be seated.
Shavasana is done at the end of all asanas, pranayama and other kriyas for 10-15 minutes daily. Shavasana can be performed without practicing any asana or other kriyas just for relaxation.
Shavasana has several very good effects. One immediate effect is that it relaxes all the muscles, nerves and the organs of the body system. When the muscles, nerves and organs are fully relaxed, they gain strength and their normal health is restored.
It is beneficial for the people suffering from insomnia, high and low blood pressure, gastric troubles, lungs and heart troubles and mental sickness etc.
It makes mind calm and relaxed. This helps improve the functioning of brain, it can cure heart related ailments, and it also brings down Blood Pressure.
Sleepiness and a restless mind are the common obstacles that prevent you from fully benefiting from Shavasana, so if you find yourself getting sleepy while in the shava-asana increase the rate and depth of your breathing.
Recovery from stress in two different postures and in Shavasana–a yogic relaxation posture.
Modulation of cold pressor-induced stress by shavasan in normal adult volunteers.