Katsugen is a way of letting the natural system of the body take care of itself by allowing it to move in the most optimum way to eject stress, toxins and other causes of illness. It trains the natural system within all of us which keeps us healthy so that it is not blunted by the arrogant attitude of the mind.
It is this arrogance of the mind that can result in undue illness, obesity, drug addictions, stress, and other mental and physical problems. The purpose of katsugen is to allow the mind to throw off its illusions and increase its receptivity to the body's natural intelligence.
Katsugen is a way to exercise and tune up your autonomic (involuntary) nervous system. It is a way of moving the body that goes beyond mere exercise or dance. It is a primal movement that arises from the fundamental root of our bodily system.
It's for people of all ages, all physical abilities, even the physically challenged.
Katsugen is a movement that is different for each person, each time that it is practiced. It is generally pleasurable and it could last from just a few minutes to an indefinite length of time. It could be done alone or with a partner but it is more private than public.
It is possible that you have experienced a mild form of katsugen. When you sit with your eyes closed, listening to music and swaying gently from side to side, completely oblivious to the external world, you are approaching katsugen.
But there is much more to katsugen than that. Quite a bit more. Words are just not adequate to describe it. Like love, you have to experience it to really know what it is like.