Position of Readiness
From a seated position, extend your legs and place the palms of your hands on the ground a few inches behind your hips. Lean onto your hands.
Press the palms of your hands and your heels downward. Bring up the squeeze and press your pubic bone upward, allowing the pressing to lift your hips off the ground. Press out through the tips of your toes. Either tuck your chin toward your chest or lift your chin, lowering your head behind you.
The musculature of the back and muscles of the legs and shoulders are stretched in this asana. The wrists become supple and elastic.
The abdominal muscles are stretched and massaged, it is very good on constipation. due to spine stretch ortosympathetic system and parasympathetic system improved by this action Purvottanasana energizes considerably the endocrine gland. It balances the hypo or hyper thyroid cases. It is also good for suprarenal glands and on the sex glands. In the case of women, the ovarian functions get back to their normal and so does the menstruation.
The kidneys are also toned and the diuresis is improved.
Hyperthyroid persons can practice this asana only without bending the head backwards.