Koga was born in Saga Prefecture. After graduating from elementary school, he entered the prestigious Kodo Gakusha judo school in Tokyo, honing his skills with the top judoka from around the nation.

Yoshida and Koga, two years apart in age, together devoted themselves in the sport at the prestigious Kodo Gakusha judo school in Tokyo. Yoshida entered the school when he was a third-year junior ...

The Japanese judokas won all seven gold medals on the first day of the Tokyo Grand Slam, which will conclude the 2024 World ...