Sensei

Sensei Wauriman Borges (5th Dan)

Meet the chief instructor of JKA NorCal, Sensei Wauriman Borges, a 5th Dan black belt and a proud member of the US National Team. Since taking the helm of the dojo, Sensei Wauriman has become a cornerstone of the local and national JKA community, inspiring students with the same dedication that made him a multiple-time National Champion of The United States and Brazil.

Trained under Oswaldo Mendonça Jr. Shihan and the famous Yoshizo Machida Shihan, President of JKA Brazil, Sensei Wauriman brings a wealth of knowledge and a deep passion for karate to every class. He is well known for his commanding presence in kumite, where his mastery of techniques like mae-geri and ashi-barai (foot sweeps) showcases his emphasis on power, timing, footwork, and indomitable spirit. In 2024 Sensei showcased these techniques at the JKA World Championships in Takasaki, Japan, breezing through the first two rounds to meet a Japanese fighter in round three.

Beyond competition, Sensei Wauriman is deeply committed to teaching students of all ages and skill levels. He believes that karate is a journey that anyone can embark on, offering opportunities for personal growth, discipline, and confidence. Whether guiding beginners or fine-tuning techniques with advanced students, Sensei fosters an inclusive and supportive environment where everyone can thrive.

With favorite katas like Jitte and Sochin that embody strength and balance, Sensei Wauriman leads by example, encouraging his students to strive for excellence both on and off the tatami. His passion for karate and teaching continues to shape the next generation of martial artists, instilling in them the values of perseverance, respect, and dedication.

JKA QUALIFICATION: Instructor C, Judge C, Examiner D

Assistant Instructors

Harrison Rahn (4th Dan)

Meet Harry Rahn, and assistant instructor at JKA NorCal. Harry regularly represents JKA NorCal and the United States as a member of the JKA USA National Team. Harry grew up doing Tang Soo Do in his home of Maryland, but began training Shotokan karate at the Tulane Karate Club under Kyriakos and Dimitri Papadopoulos in 2013 before moving to California and joining JKA NorCal in 2018. Harry also spent several months at the JKA World Headquarters, immersing himself in training to prepare for the 2024 World Championships.

As a two-time Panamerican finalist and a World semifinalist, Harry has shown diligent training will garner results at the world level. One of his favorite memories is hearing the roar of the US team cheering him on after his first victory during elimination rounds at the 2023 Panamerican Championships—a moment that reaffirmed his passion for competition and teamwork.

Now, Harry is setting his sights on fostering the JKA NorCal Competition Team and continues to focus on diligently training for upcoming international competitions. He credits karate with providing the structure that helps him set goals and maintain focus in all aspects of his life, so Harry is thrilled to share the lessons he earned while training at the JKA World Headquarters with students of all ages, helping them build confidence, discipline, and a lifelong love for the art.

Sammi Yeung (3rd Dan)

Sammi Yeung, has over a decade of experience training and competing with JKA NorCal. A women’s kumite national champion and three-time United States national team member, Sammi has represented the U.S. in kata, kumite, and team events at the highest levels of competition.

Having transitioned from the JKA-USA youth team to the adult team, Sammi brings a unique perspective to young students eager to grow through competition. She hopes to inspire the next generation by sharing her journey and the lessons she’s learned along the way.

One of Sammi’s most memorable moments was competing in the Women’s Team Kata finals at the 2024 Gichin Funakoshi World Cup where the United States took 4th place in the world. Performing for the U.S. on the main tatami under the stadium’s spotlight, she vividly recalls the adrenaline, heightened senses, and surreal realization of achieving a childhood dream.

Sammi is thrilled to train alongside and instruct the up-and-coming members of the JKA NorCal Competition Team, offering her mentorship to inspire and encourage them as they pursue their goals. While karate presents both physical and mental challenges, it does so within a supportive and inclusive community. Sammi is dedicated to fostering an environment that embodies these values, empowering students to overcome new challenges and achieve the same sense of fulfillment that karate has brought her.

JKA NorCal Founder

Sensei Christina Foo (6th Dan)

Christina began her karate training in 1990 under Sensei Jose Ferrand, chief instructor at the Miami Shotokan Karate Club who was the major influence introducing her to the competitive arena early on. She became a seasoned competitor and a staple member of the US team. Her commitment and dedication to training earned her several national and international awards including National and Panamerican Championships.Sensei Christina achieved Godan in 2010 under Sensei Kurasako and Rokudan in 2017 under Sensei Imura of JKA Headquarters.

In 2000, Christina moved to the San Francisco Bay Area for her career as a Marketing Manager in the Silicon Valley. During this time, she continued to compete while coaching and mentoring upcoming karate-kas. Her passion for the discipline and the community propelled her to hone her instructing skills and a take up a mentoring role within JKA NorCal. Sensei Christina has since returned to Miami to continue training with Sensei Ferrand, but she still remains as a strong advisor to JKA NorCal and an endless trove of sagely advise and cheer.