One who is not comfortable forming the complete Shalabhasana posture, should initially try Ardh-Shalabhasana. The difference between Ardh Shalabasana and Shalabhasana is that in Ardh Shalabhasana , one does not have to lift both legs up simultaneously, but one at a time. If you are raising left leg one time, then follow with right leg the next time. Likewise, lift and bring down alternate leg at a time.
This yoga exercise should be repeated three times for each leg i.e. in total six times for both legs. This asana enhances the efficiency especially of the lower elements of the human body from the toes up to the navel. This asana also boosts the flexibility of the spinal cord. Ardh-Shalabhasana aids in blood circulation in the upper part of the body thus also enhancing the efficiency of mouth, eyes, lungs, chest, neck and shoulders.
Customary practice of this yoga exercise eliminates ailments of the stomach, renal and liver disease; you also become immune to flatulence, indigestion, hyper-salivation, urinary retention etc. This asana helps to avoid acidity, develops your appetite and curtails mental frustration and invigorates your memory. Ardh-Shalabhasana is instrumental in avoiding gynaecological disorders.
Important: It has been seen that some yoga disciples, have been able to lift their body up to their chest and make an angle by keeping their hands on their hips. Kumbhaka (breath retention) is also possible with this asana.