When he was 7 years old, Mehrdad Valian ran into two school bullies and realized that he didn't know how to defend himself. That moment shaped the course of his life, inspiring him to train in Tehran and pushing him down a path of kung fu. In the four decades since, he has won first-place titles in martial-arts competitions across the world, tied on eighth-degree black belts in tae kwon do and kung fu, and transformed into Master Mehrdad Valian.

Fresh off wins in Iran and Russia, Master Valian settled in Texas and began his own tae kwon do studio in 1995, where trainees of all ages swear by a five-item oath. In the spacious facility, students of different ranks train together while observing the sport's tenets—including courtesy, integrity, and perseverance—and maintaining enough self-control to continue using doorknobs instead of kicking through every door they see.