Yoko Gushiken - "Fist"
The legendary Yoko Gushiken (23-1, 15) was one of the all time great Japanese fighters. His lengthy reign with the WBA Light Flyweight title saw him record 13 defenses, and he later went on to open a gym, and lead several fighters, including Daigo Higa, to world titles.
What few might be aware of is that Gushiken had success outside of the ring. That included a musical career that included his 1979 track "Fist", which you can hear below along with releasing books and being involved in advertising.
Gushiken's success in the recording studio is certainly not close to his boxing success, but it's still an interesting thing to be aware of. Also to think this came out whilst he was still a reigning world champion is also kind of interesting.
Some things don't fit in elsewhere on the site so have been put here as a result.