Halasana is also known as Kalapoy asana, Full Plough Posture ,Full Plow Pose Purn Hal Asan.
Should be avoided during pregnancy and menstruation, high blood pressure and brain diseases.
Should be avoided if suffering from an enlarged thyroid, spleen or liver as well as cervical spondylitis, slipped disc, neck problems, headache and weak blood vessels in the eyes
You should not do halasana if you have any neck problems. If you suffer from "rounded shoulders" a.k.a. kyphosis, do not stretch too far and do not hold the posture too long.

Benefits -
Brings fresh blood to the throat and thyroid gland.
During the inhalation intense pressure is applied to the abdomen giving a good stimulation to the digestive system

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