Friendly and Focused Training to Help You Reach Your Goals

Whether interested in improving fitness and wellness, self-defense, school focus and grades, self-confidence to avoid bullying, or living a more disciplined and focused life, Karate Fit USA offers a wide variety of classes and methods in Lawrence, NJ for our students and instructors to master Body, Mind and Spirit!


We have been teaching martial arts in Lawrenceville for over 30 years (and training longer!) in a family-friendly environment, welcoming all ages and abilities. We use self-defense and fitness skills to improve as practitioners and grow as people. Our experienced staff is dedicated to providing the highest quality training and instruction so that you can achieve your goals.




“My family and I have been members here since 2013. It’s a fun, family-oriented place to learn Martial Arts, not to mention getting and/or staying in shape. The instructors are extremely knowledgeable and caring. Having tried the fad gyms & workouts with little or not results, this was a last resort for me personally. Since attending Karate Fit USA’s karate classes and fitness classes, I’ve lost over 20lbs, and I’ve regained confidence and energy that I haven’t had in years. We plan on being members for a long time to come.”
– Jon McNiece

“I started at Karate Fit USA in the summer of 2003 at 10 years old. I was HOOKED instantly. I loved attending classes where I felt included and important. I could learn at my own pace and I learned to set my own goals with the guidance of strong leaders around me. I received individualized attention and learned various skills that I can honestly say is the #1 reason I have succeeded in so many areas of my life (other sports such as tennis, track, college cheerleading and most importantly, in school, and relationships, and my self-worth). For 8 years of my life the instructors and my fellow peers at Karate Fit USA took the time and energy to invest in me. The training I received like so many others help to make healthy, happy, and successful leaders and members of the community!”
– Cassie Lynn

“My son started karate at 5 years old with the wonderful team at Karate Fit USA. I cannot emphasize how beneficial it has been to him in all aspects of his life. His focus and commitment to academics and organized sports is a direct result from karate at this school. Thank you!”
– Lillian Leigh

“I’ve had the privilege to teach Small Circle Jijitsu at Karate Fit USA since 1994 and have always found his students respectful, energetic, and willing to learn. Some of the best I’ve encountered.”
– Professor Leon Jay




Kristen Updike-Black
Kristen Updike-BlackFounder
Kristen began training in the 90s, and her passion for the martial arts led her to establish Karate Fit USA at our current location, as well as a sister school in SC!
Mark Swingle
Mark SwingleOwner and Chief Instructor
Sensei Swingle came to Karate Fit USA in 2004, having already earned multiple black belts in other Japanese martial arts, including 10 years living in Japan. He has been training since 1986, and is looking forward to another 30 years of improving!
Dominick Piccinetti
Dominick PiccinettiSenior Instructor
Sensei Piccinetti started in our Little Ninja Program, and has continued to train hard and earn his 3rd Degree Black Belt. He runs most of the kids’ programs, and knows a lot of Tournament and Grappling tricks for our kids and adults alike!
Charles Christine
Charles ChristineInstructor
Edgar Relevante Sr.
Edgar Relevante Sr.Instructor
Edgar Relevante Jr.
Edgar Relevante Jr.Instructor
Grandmaster Black
Grandmaster BlackSpecial Advisor
Grandmaster Black is focused on the SC school, but continues to visit our school for seminars, tests and advanced training, sharing his decades of experience with various martial arts and Chinese healing and pressure point knowledge.
Leadership Team
Leadership TeamFuture Instructors!
Our Leadership Team is comprised of motivated teenagers who want to grow not only as practitioners, but as role models and assistant instructors for others. Our LT Program helps them develop these skills and continue their progress toward becoming Sensei.

Interested In Learning More?

Fill out this brief Request Info form to learn more about Karate Fit USA