Home to the only Gracie Jiu-Jitsu BROWN BELT in the Twin Ports Area


Due to the incidents that occurred at Sandy Elementary School we have decided to lower our prices for everybody in the Twin Ports Area. We understand that due to economic hardship that many families can't afford to send their children to martial art schoolsalso. So our facility has dropped its prices to help out. Now for any child under the age of 16 years of age it is $50.00 to train at the facility, and is only an additional $10 for any other martial art they may want to do. If they want to do just Karate it is $50.00 a month. If they want to do Karate and Gracie Jiu-Jitsu it is $60.00 a month.
We also lowered our prices for the adults as well, and lowered our prices for Families as well. Please give us a call today at 920-475-7022 and we can let you know about all the prices for the facility. Our prices are lower than all our competitors and we offer effective martial arts training for anybody wanting to get in shape, make new friends, learn self-defense, or compete in MMA, Karate, Gracie Jiu-Jitsu, or Muay Thai Kickboxing.
We dont want to see what happened at Sandy Elementary happen here in the Twin Ports so we also have trainings at a reduced rate for Teachers, Police Officers, and Firefighters at $50.00 a month. We just require you to show current employment or identification card/badge.

Thank you everybody and see you soon!!!!
Team Inner Strength Martial Arts



Here at Inner Strength Martial Arts we offer Gracie Jiu-Jitsu, Muay Thai Kickboxing, American Karate, Mixed Martial Arts and Women's Self-Defense classes structured to help you achieve your goals, help you get in better shape, and teach you how to defend yourself in a life or death situation.

Who We Are

In 2009 Robert Mrotek formed Inner Strength Martial Arts in Superior, Wisconsin. Inner  Strength Martial Arts is a full-time martial arts facility offering American  Karate, Little Billies, Gracie Jiu-Jitsu, Muay Thai Kickboxing, Women’s Self-Defense, Mixed  Martial Arts, Cardio and Conditioning, and Plyometric Courses. Inner Strength  Martial Arts has over 20 MMA fighters training out of the school, and is the  only full time martial arts facility in the Twin Ports Area.

What We Do

Through a dedicated, systematic, and intensive martial arts program, Inner Strength Martial Arts produces the incentive to become a more confident individual both physical and mental regardless of age or sex. These programs offered at Inner Strength Martial Arts will help you become a better student in school, a more focused individual in the workplace, and teach you how to be a leader in society.

Inner Strength Martial Arts is a black belt school, a family school, a school that everybody can be proud to be a part of. Our goal is to offer a family friendly environment where everybody can be part of a successful team, and work together to help each other achieve their goals and their dreams.

Here at Inner Strength Martial Arts we strive for each and every student to learn what it means to be loyal, respectful, trustworthy, dependable, and honorable. The martial arts are more than learning how to defend yourself; it makes you into a special kind of person that is difficult to find in today's society. Here at Inner Strength Martial Arts everybody is going to learn to work as a team, and to be there for one another as a family.


When We Do It

5:30-6:00 Little Billies Kids Karate/Family Karate
6:00-6:15 Dodge Ball Conditioning Game
6:15-7:15 Muay Thai Kickboxing
7:15-9:00 Gracie Jiu-Jitsu (Adults and Children)


Mondays, Wednesdays, Fridays 10:00-Noon: Gracie Jiu-Jitsu/MMA Training


Mondays, Tuesdays 5:00-5:30 Competition Team Forms Training


9:00-11:00 Little Billies Kids Karate/Family Karate
9:00-11:00 Gracie Jiu-Jitsu/ Muay Thai 11:00-12:00 Competition Team Weapons Training (BO)


****If Local Schools are closed due to bad weather then Inner Strength Martial Arts is also closed for the evening****