This is the half boat pose. First sit on the floor with the legs stretched out in front of you. Link your 
fingers behind the back of your head. Exhale and recline the trunk while you raise both legs off the floor. Here you are resting only on the buttocks, keeping the knees straight and the legs at an angle of roughly thirty five degrees. Hold this pose as you breathe easily for thirty seconds. Then slowly release back down to the ground.
PRECAUTION: Pregnancy or injury.
BENEFITS: Ardha Navasana works on the liver, gall bladder and spleen. In the beginning, the back is too weak to bear the strain of the pose bring life and vigour to the back.