From 1922-1932 Chitose Sensei went to college, practiced karate in his spare time,and assisted his old school teacher Gichin Funakoshi with his college karate classes. In 1931 Chitose Sensei assisted a new student at the Takushoku University karate club. His name was Masatoshi Nakayama (1913-1986), who would one day be the head instructor of the Japan Karate Association (Shotokan). After he completed his medical training, Dr. Chitose served in the Army Medical Corps and spent some time in China. While serving in a small village in China Dr. Chitose befriended the local citizens and trained in Chinese Gung-fu. In 1936 O-Sensei may have been present at a meeting of Okinawan karate authorities in Naha, Okinawa. This was the meeting in which the translation "Empty Hand Way" was actually adopted for Karate-do in place of the original todejutsu or "Chinese Hand Method"

 

In March 1946 Doctor Chitose opened a small karate dojo in Kikuchi City, Kumamoto Prefecture. He later held an Okinawan Kobudo Taikai (Martial Arts Tournament) at the Kubukiza in Kumamoto City to help raise relief funds for Okinawa. In 1948, Dr. Chitose, organized the All Japan Karate-do Federation (Zen Nihon Karate-do Renmei) along with Gichin Funakoshi, Mabuni, Higa Seko, and Toyama Kanken and served as president for some time. It was around this time that O-Sensei, as Dr. Chitose was called, named his style Chito-ryu. "Chi" is derived from "thousand" and "to" is from the Chinese "Tang", hence the translation of Chito-ryu is "The thousand year old Chinese (Tang dynasty) way", signifying the ultimate origin of Karate as being from China during the Tang era roughly one thousand years ago. (Of note, "O-Sensei" is not a common 'nickname' in Japan, is used by some martial arts organizations and not others, and roughly translates as THE Sensei.)

In 1958 O-Sensei attained the the rank of Juudan -- the highest rank obtainable in martial arts -- from the ZEN OKINAWA KARATE KOBUDO RENGO KAI (The all Okinawa Karate and Weaponry association).

At this time the practice of most martial arts (kendo, judo and others associated with the nation of Japan) had been forbidden by the allied powers under the command of General Douglas MacArthur. Karate was considered an Okinawan art form and was not subject to the close scrutiny given to Kendo and Judo. Nevertheless, Doctor Chitose and other martial arts teachers were very secretive in the teaching of their respective arts. Much of the martial arts training was camouflaged as physical fitness exercises and dances. In most instances the occupying powers just looked the other way.