The arts of Japan have roots that predate influence from the mainland. At the sametime almost everything in Japan has been infused with multiple influences from the mainland, as well.
Kiko is no different. It's roots stretch back to the dawn of humans on the archipeglio. But what we see in in the parks in Japan today mimics Chinese Chi Gong almost exactly. but Kiko in Japanese Mikkyo retained much of what went on before as well; mixing and merging ancient Japanese practices with what was brought from the mainland as well.
Japanese Culture is both what was before and what was brought. This is seen strongly in Zen. Zen is the what was created in Japan with the ancient matured in Japan through the influence of Chinese Confusionism, Buddhism, & Taoism.