The word sarpa means snake. Lie down on your stomach keeping your face downwards. Stretch your body with heels and toes joined to each other. Catch the wrist of your left hand with your right hand on back. Now raise your neck and legs in such a manner that body lies mainly on the stomach and assumes the position of snake.
It gives very good stretching to visceral organs like stomach, colon. This improves the muscle tone and functioning of these organs.