Definition - What does Side Headstand mean?
Side headstand is an intermediate to advanced variation of headstand that requires the yogi to have a solid practice and to be able to move into, hold and move out of headstand safely and correctly. In side headstand, the yogi twists and opens the body to both sides.
Entered from rom headstand, with the legs engaged and together and the feet active; the yogi initiates a twist from the center of abdomen, which twists the lower body away from the upper the body either to the left or right.
Side headstand is known as parsva sirsasana in Sanskrit.
Yogapedia explains Side Headstand
Inversions are therapeutic asanas, as they increase circulation to the head, upper body and flush the lymphatic system. By adding the twist, the restriction and subsequent flush of oxygen-rich blood to the upper body is increased. In side headstand, keeping equal pressure on both forearms allows the neck to be free from tension and will aid in keeping the shoulders in one line. The supporting forearm typically opens in the direction of the twist, which allows for opening across the chest.
Alignment in side headstand is more important than deepening the twist, if the shoulders are not in one line, the side waist will collapse instead of twist. To exit the posture, the yogi untwists the body and comes back to the starting position, then moves into child pose to repeat the posture on the other side.