Phone: 925-753-1167
Email: [email protected]

D1 & Only Martial Arts Academy
3385 Deer Valley Road
Antioch, CA 94531

Business Hours:
Mon-Thur 4pm-9pm
Friday 4pm-7pm
Saturday 9am-11am
About Us2019-03-06T09:36:18+00:00


The purpose of D1 & Only Martial Arts in Antioch, CA is to create a friendly, family-oriented environment where people feel welcomed and special. It is to provide our students with the most comprehensive, realistic and effective self-defense system available. We strive to make a positive impact in their lives through our various character enrichment programs, which focus on leadership, academic performance and teaching basic financial principles.

Our objective is not to create world champions; it is “Developing Life Champions!”



In 2000, our school’s founder, Master Tim Calvin purchased Pallen’s Martial Arts from one of his instructors, Professor Joseph Pallen. At that time, we only taught Senkotiros Arnis (Philippine stick and knife fighting) and Kajukenbo, which is a hybrid street fighting art comprised of Karate, Judo and Ju-Jitsu, Kenpo Karate and Chinese and Western Boxing.

In 2005, Master Tim changed the name of the school to Delta One Martial Arts and Fitness Center and he incorporated Brazilian Jiu-Jitsu and Kickboxing into our curriculum.

In 2014, Master Tim saw the necessity for yet another change, modernizing our system to fit the self-defense needs of today’s society and creating an exciting program designed to help people mature, develop and grow to reach their full potential.

To complete our well-rounded martial arts program, known as the Kajukenbo “Urban Self-Defense” System, we included Krav Maga, a highly effective self-defense system created and taught by the IDF (Israeli Defense Forces) into our curriculum. We saw that by blending key concepts and techniques from the different martial arts programs we taught into one system, it made that system highly effective and extremely practical for today’s urban environment. Our students are now capable of defending themselves standing, on the ground, against multiple attackers and attackers with various weapons, such as knives and guns. They are also capable of utilizing sticks and knives as a practical and realistic means of defending themselves.

Tiera Calvin


We are not your average, every day, run of the mill martial arts facility. We’re different and we love it and pride ourselves on it! We strive to be exceptional, innovative, creative, unique and one of a kind. We are D1 & Only Martial Arts!


  • YET (Young Entrepreneurs of Tomorrow): YET teaches our students about basic financial and business principles.
  • LOT (Leaders of Tomorrow): LOT helps our students develop their leadership skills and abilities.


  • Kids Only, free group birthday parties each month to help celebrate a special day
  • FREE Parent’s Night Out each month so you can have a date night, a night out with the guys or girls, or just a night to relax while the kids have fun at the school playing video games, dodgeball, watching movies, or a host of other fun-filled activities
  • Picnics and numerous parties throughout the year


  • Free anti-abduction seminar
  • Free bully prevention seminar
  • Free women’s self-defense seminars
  • Cancer awareness and fundraiser event, “Kick Cancer to the Curb” where we raise money for a person battling cancer to help with their financial needs


Master Tim Calvin
Master Tim CalvinFounder & Instructor
Master Tim is the founder of D1 & Only Martial Arts Academy and the Kajukenbo “Urban Self-Defense System”. He has trained in the martial arts for 23 years. He has a Bachelor’s of Science (B.S.) degree in Business Management and a Master’s in Business Administration (MBA) degree from WGU (Western Governor’s University). Master Tim is a former police officer with the Oakland and Novato Police Departments, where he worked as an Undercover Narcotics Officers, Defensive Tactics Instructor and SWAT Team Member. He also served (6) years in the United States Marine Corps.

• 5th Degree Black Belt in Kajukenbo
• 5th Degree Black Belt in Senkotiros Arnis,
• Certified Level II Krav Maga Instructor
• Certified Kickboxing Instructor
• Blue Belt in Brazilian Jiu-Jitsu
Sifu Jarell Calvin
Sifu Jarell CalvinChief Instructor
Sifu Jarell is the Chief Instructor of D1 & Only Martial Arts Academy. Sifu Jarell has trained in the martial arts for 19 years. He has an Associates of Arts (A.A.) degree in Liberal Arts (Math and Science) from Los Medanos College and he is working on earning his Bachelors of Science (B.S.) degree in Business Marketing from WGU (Western Governor’s University).

• 4th Degree Black Belt in Kajukenbo
• 1st Degree Black Belt in Senkotiros Arnis,
• Certified Level I Krav Maga Instructor

Sifu Jarell was an amazing competitor. He was a National Champion in Open / Creative Forms and he won 4th place in sparring at the Super Grand “World Games” in the National Black Belt League (NBL) in 2011. He is also in charge of our Demonstration Team and he has created and performed demos for the Sacramento Kings and the Golden State Warriors half-time shows.

Donna Twitchel
Donna TwitchelProgram Director
Coming Soon

Developing Life Champions

We provide a comprehensive self-defense program that makes a positive impact on our students’ lives