I would prefer that we be very careful around the term "aiki." From my experience in Japan, it appears that any activity can be considered a path to enlightenment, as long as it is followed with a certain intent. That being said, no activity that lacks this intent would get you there.
That's a common view in Buddhism generally, not just in Japan. That the path to enlightenment leads through mindfulness and meditation, which can take place in the context of many many outward forms.