Originally from Oahu, Hawaii, Zach Kaina and his family relocated to Costa Mesa, California at ten years old to pursue his jiu jitsu journey at AOJ Academy. Arriving as an orange belt, he joined the AOJ Kids Program and closed out his youth competition career with seven Pan Kids titles. As a juvenile competitor, Zach won major IBJJF Championships and established himself as a promising young talent and an integral part of the AOJ competition team. In December of 2022, Zach was awarded his black belt by Professor Gui Mendes on the podium after winning the brown belt division at the NOGI World Championships. In 2024, he captured the NOGI World title as a black belt, completing the journey from AOJ Kids Program to homegrown world champion, and becoming an inspiration to the next generation of AOJ kids he now helps guide and teach.