Circulation
There are about 4 litres of blood in the human body, and about 3–4 times that much lymphatic liquid that collects the wastes and pathogens from the body and transfers them to the blood vessels in the 600–700 lymph nodes of the body. The artery circulation is only 25 % of the blood, about one litre.
All other liquids are in the low pressure systems which are easily and usually disturbed by immobility, conventional sitting with its large pressure areas in thighs and pelvic area, tense back and shoulder muscles, and pressure in the stomach due to slouching and tight clothing.
Sitting on a two-part saddle chair, and especially on an active seat, and wearing loose clothes can help to keep circulation and metabolism at a much healthier level.