Routine practice in traditional Japanese arts, such as kendo, ikebana (kado), calligraphy (shodo), etc., is called keiko. I came back to my kendo practice after a couple of weeks of absence and immediately felt the familiar sense of structure and certainty in the next action during the keiko.
With such a strong emphasis on routine and structure, it is almost surprising that, at a certain level, martial arts provide an opportunity for self-expression and creativity. I think creativity is linked to one’s ability to relax, both physically and mentally. Being relaxed allows one to make creative decisions without analyzing them (the much-talked-about state of “no-mind” or mushin,) but achieving this state is a skill, and such, it required some grinding and structured practice.