MJ Fitness & Kickboxing

MJ Fitness & Kickboxing We Are Danbury’s #1 Transformation Program. Results-focused, Community-driven. We're Dedicated To Transforming Lives.

Bio
Former European Full Contact Karate Champion Mariusz Janicki is the founder and owner of MJ Fitness & Kickboxing . After more than 12 years of competing as a top level full contact fighter, Mariusz has retired to pursue his passion for helping others in achieving their fitness goals. Whether you are looking to lose weight, tone muscle, improve cardio, or simply live a healthier lifestyle, his

focus is on you and your personal fitness needs. In addition to fighting, Mariusz has taught as a PE Teacher and Martial arts Instructor working with kids, adults, and professional athletes alike. Mariusz is always researching new training methods and ways to provide his clients with the most functional and effective workouts possible. With accomplishments such as two-time Polish Full Contact Karate Champion, four-time US Lightweight Champion, and amateur Muay Thai/K1 rule record of 8-2, Mariusz has seen, experienced, and mastered a variety of training styles from around the world. This first-hand fighting experience paired with a background in Body Building and Strength Sports Training, Boot Camp, Martial Arts, Personal Training and more, you can be sure Mariusz will help you both mentally and physically in achieving your fitness and weight loss dreams. Education/Certification
Master's Degree in Physical Education (2003) Wroclaw, Poland
Certified Trainer of Body Building and Strength Sports (2003) Worclaw, Poland
Martial Arts Instructor
Certified Personal Trainer
Certified Professional Nutritionist
Certified Boot Camp Instructor
Certified CPR / AED

🇺🇸 HAPPY MEMORIAL DAY 🇺🇸We honor and remember the brave men and women who made the ultimate sacrifice while serving our ...
05/25/2026

🇺🇸 HAPPY MEMORIAL DAY 🇺🇸

We honor and remember the brave men and women who made the ultimate sacrifice while serving our country.

Spartan workout crew 💪🔥Sweaty, tired, and one step closer to race day 🏔👊Nothing easy about these workouts… but that’s ex...
05/23/2026

Spartan workout crew 💪🔥
Sweaty, tired, and one step closer to race day 🏔👊
Nothing easy about these workouts… but that’s exactly why we do them.
Strong team. Strong mindset. Strong finish.

💥 MEMBER SPOTLIGHT: Estefany’s Incredible Transformation ⚽🔥Big congratulations to one of the younger members of our MJ F...
05/20/2026

💥 MEMBER SPOTLIGHT: Estefany’s Incredible Transformation ⚽🔥

Big congratulations to one of the younger members of our MJ Fitness family — Estefany 👏

As an avid soccer player, Estefany originally joined our program alongside her mom with the goal of improving her athletic performance. But along the way, she achieved so much more than that.

She committed herself to improving her overall fitness, wellness, strength, energy, and health — and the results have been absolutely incredible.

In just 2 short months, Estefany has:

💥 Lost an astonishing 15 lbs
💥 Burned 9.1% body fat
💥 Improved her athletic conditioning and endurance
💥 Built a stronger, healthier, and more confident version of herself

And honestly… it’s no surprise.

Because Estefany followed what we always call our “magic recipe”:

✔️ Hard work
✔️ Consistency
✔️ Clean, balanced nutrition
✔️ Trusting the process

Workout after workout, she showed up ready to push herself, improve, and give her best effort. That mindset is exactly why she’s seeing such amazing results.

What makes us especially proud is seeing young athletes like Estefany learn healthy habits early in life — understanding that fitness isn’t only about appearance, but about performance, confidence, energy, discipline, and long-term health.

Estefany, we are so proud of your dedication and your progress. Your journey is inspiring, and this is only the beginning for you both inside and outside of sports 🔥⚽💪

If you’re reading this and want to improve your fitness, health, confidence, or athletic performance — our team is here to help.

👉 Reach out today to schedule your FREE consultation with one of our Transformation Coaches.

Sometimes one small step can completely change your future.

— MJ & The Team

05/19/2026

This is more than just a workout… It’s stress relief, confidence building and getting stronger one combo at a 🔥🥊

WE DID IT AGAIN - OVER $5,700 RAISED for Regional Hospice’s Tender Hearts Program ❤️Thank you very much to all of our me...
05/18/2026

WE DID IT AGAIN - OVER $5,700 RAISED for Regional Hospice’s Tender Hearts Program ❤️

Thank you very much to all of our members, coaches, staff and local community for your generous donations and support 🙏

​Special thanks to our Event Committee for their huge help to organize and pull this event off.

​Without your help, we couldn’t have made our 6th Annual BEAT CHILDHOOD CANCER Fundraiser event such a great success! We are honored to be able to support this amazing nonprofit, Regional Hospice’s Tender Hearts Program in Danbury , where all proceeds go straight to brave kids battling cancer and their families.

Big shoutout to our local vendors and contributors: 🙏👇

VIP Sponsors:
• Service Stars HVAC,
• Strength Of Mind Psychiatry,
• Growth Media, Marketing Agency .growthmedia
• Western Connecticut Orthopedic Surgical Center, wcosc.org
• Custom Care Building Services, customcarebuildingservice.com
• Ives Bank,
• JAR Associates llc, jarpropertymanagement.com

Vendors:
• Oscar from Tacos La Michoacana,
• Nicole from Little Smiles, Face Painting by Nicole,
• Laura from Zwilling,
• Adam from Crepe Royale,
• Brittney from Muse Squad,
• Julissa from Twelve Twenty Eight,
• Nassar Contracting LLC,
• Barbara from Necessary Escentials,
• Claudia from Jenny’s Charm Bracelets and Accessories,
• Yvan from YLS Photo Phactory,
• Jackie from Interlinked By Jackie, interlinkedct.com
• Diane from Bookmarks, Pens & Gifts
• Lisa from Wooden Signs & Art
• Danbury Police & K-9

We have the best community around! ❤️🙏

-MJ Fitness & Kickboxing

05/14/2026

Partner finisher brought by Coach Sam 🔥💪
High energy, teamwork, and a strong finish to class 👊

💥 MEMBER SPOTLIGHT: Wilson’s Incredible Start 🔥Big congratulations to Wilson for an incredible start to his transformati...
05/13/2026

💥 MEMBER SPOTLIGHT: Wilson’s Incredible Start 🔥

Big congratulations to Wilson for an incredible start to his transformation journey! 👏

Just 2 months ago, Wilson joined MJ Fitness & Kickboxing with a serious goal in mind — not only to lose weight and get leaner, but more importantly, to improve health issues that were becoming a real concern and were strongly recommended by his doctor to address.

Like many hardworking dads, Wilson had a full plate. Work, family responsibilities, long days, stress… it’s easy to put your own health last.

But Wilson made a powerful decision:
He decided it was time to take control of his health, energy, and future.

And in only 2 short months, the results have been incredible:

💥 20 lbs down
💥 6% body fat burned
💥 Stronger and leaner
💥 More energy
💥 Feeling and looking better than ever

But what makes us most proud isn’t just the physical transformation.

It’s seeing someone regain confidence, improve their health, and realize they are capable of far more than they thought possible.

Wilson showed up. He stayed consistent. He trusted the process. And day after day, the hard work started paying off.

This is exactly why we do what we do at MJ Fitness & Kickboxing.

Because transformation is about more than weight loss. It’s about improving quality of life, reducing stress, gaining energy, building confidence, and becoming the healthiest version of yourself for both you and your family.

Wilson, we are incredibly proud of you. And the most exciting part?

This is only the beginning. 🔥

If you’re reading this and know deep down that it’s time to start taking better care of yourself, let this be your sign.

You do not have to do it alone.

Whether your goal is to lose weight, improve your health, gain strength, reduce stress, or simply feel better again — our team is here to help.

👉 Reach out today and schedule your FREE consultation with one of our Transformation Coaches.

Sometimes one conversation can change everything. 💪

— MJ & The Team

ONLY 4 DAYS LEFT to our 6th Annual BEAT CHILDHOOD CANCER Fundraiser ❤️Don’t forget to grab our official fundraiser T-SHI...
05/12/2026

ONLY 4 DAYS LEFT to our 6th Annual BEAT CHILDHOOD CANCER Fundraiser ❤️

Don’t forget to grab our official fundraiser T-SHIRTS before they are gone, and rock on this Saturday, May 16th.
We’re asking for a minimum donation of $25 to benefit Regional Hospice's Tender Hearts Community Pediatric Program in Danbury, CT.

Join us this Saturday, May 16th, 2026 at 12pm for an outdoor event in our parking lot to support this great cause.

Since we opened our doors, it was always our goal to give back to those who need it the most and be part of something meaningful.
Our goal is to raise $5,000, but we will do our best to raise the most funds possible to support these young warriors and their families battling cancer.

Please help us support Regional Hospice's Tender Hearts Community Pediatric Program in Danbury, CT by making a donation through our fundraising page. Even a small donation will help us achieve our goal! The process is fast, easy, and secure.

Please help us support these brave warriors by making a donation through the link below👇
https://regionalhospicect.networkforgood.com/events/96505-mj-fitness-kickboxing-pediatric-cancer-fundraiser

Regional Hospice's Tender Hearts program provides specialized comfort care services for infants, children, teens, and young adults under 21 years of age. Their family-centered approach ensures that every young patient receives the expert, compassionate care they deserve.

Every dollar counts. Your tax-deductible gift will help make an impact by enabling Regional Hospice's Tender Hearts Community Pediatric Program to honor the strength of young cancer fighters and to help ensure compassionate care, comfort, and support for children and families facing serious illness. Every punch, kick, and rep represents hope, resilience, and solidarity with those who need it most.

Please stop by on May 16th to drop your donation and Join Our Free Community Bootcamp at 12 Noon, Meet Our Coaches, Local Vendors, Raffle Prizes, Live DJ, Bounce Castle, Fire Truck, K9, Giveaways, Photo Booth, Family Fun and much more👇

💗12pm-12:40pm Free Community Bootcamp
💗1:30pm-2:00pm Free Community Zumba
💗12pm-2:45pm Live DJ, Giveaways, Collect Donations for Regional Hospice & have a good time!
💗2:45pm-3pm Raffles

🚨 Attention Local Businesses & Vendors! 🚨
Want to showcase your business while supporting a great cause? Join us for our upcoming fundraiser!
This is a fantastic way to give back to the community while gaining exposure for your business.
📩 Contact us directly to secure your spot!

Thank you very much for your support!
MJ Fitness & Kickboxing

*In case of bad weather conditions, we will move our event indoors*

🎉 Big congrats to our Step Challenge Winner: Liz! 👣💪We are beyond inspired by every single member who laced up, stayed a...
05/12/2026

🎉 Big congrats to our Step Challenge Winner: Liz! 👣💪

We are beyond inspired by every single member who laced up, stayed active, and showed up day after day. The consistency, effort, and motivation from this group was amazing to watch 🔥

Let’s keep that momentum rolling!
Take advantage of this beautiful time of year ☀️
Go for walks, hit the trails, play with your kids, take the dog out, stay moving, and enjoy being active.

Most importantly — continue inspiring the people around you to move more, feel better, and live healthier lives 💚👊

Address

5 Shelter Rock Road, Building D, 2nd Floor (next To DMV)
Danbury, CT
06810

Opening Hours

Monday 6am - 9pm
Tuesday 6am - 9pm
Wednesday 6am - 9pm
Thursday 6am - 9pm
Friday 6am - 9pm
Saturday 6am - 12pm

Telephone

+2038854580

Website

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