His health improved to such an extent that he became a leader of the school's karate club, and his friends dubbed him Chippaii Matsu, a nickname meaning "tenacious pine tree".

After graduation in March 1928, he began to study martial arts full-time, moving to Shuri and training under Taro Shimabuku (島袋善良)and Ankichi Arakaki.

During his time as a police officer, Nagamine received further instruction in karate from Chotoku Kyan and Motobu Choki, and achieved the title of Renshi in 1940.

Nagamine retired as a policeman in 1952, and in 1953 he returned to Naha City and set up his own dojo, which he named "Matsubayashi-Ryu Kodokan Karate and Ancient Martial Arts Studies".

Tales of Okinawa's Great Masters was translated into the English language by Patrick McCarthy [Bubishi], and published in 2000, by Charles Tuttle.