Sohan Yoshioka, born in 1971 in Saitama Prefecture, Tokyo, was profoundly influenced by his grandfather, a master swordsman.

Trained in martial arts from a young age, he had to abandon his practice due to a severe incident. However, a life-changing event in high school led him to resume his martial arts journey under the guidance of Soshi Ito Ryuji.

Excelling in various diciplines, Yoshioka earned multiple black belts and won numerous full- contact karate championships. His expertise spans Kyokushin Karate, Ashihara Karate, Enshin Karate, Kendo, and Shotokan Karate. Recognized as a Grand Master by the International Karate Association and the Bushin Karate Do Federation, he established the Seikenkai Karate School in 2001, later re- named Karatedo Seiken-Kai in 2006.

This organization is known for its rigor- ous curriculum, focusing on Oki-nawan Karate Kata,Kobudo, and Sabaki techniques.