Welcome to CrossFit Arsenal- Fitness and Jiu Jitsu, where we are dedicated to providing the highest quality Brazilian Jiu-Jitsu training in a supportive, family-friendly environment. Our mission is to empower students of all ages and skill levels through the art of BJJ, fostering physical fitness, mental resilience, and personal growth.
At CrossFit Arsenal- Fitness and Jiu Jitsu, we believe that Jiu-Jitsu is more than just a martial art—it's a way of life. Our approach combines technical excellence with practical application, ensuring that our students develop skills that work both on and off the mats.
Whether you're looking to compete at the highest levels, learn self-defense, or simply get in the best shape of your life, our expert instructors are here to guide you every step of the way.

Head Coach - Black Belt
15+ years of experience competing at the highest levels.

Kids Program Director - Brown Belt
Specializes in teaching children of all ages and abilities.

Competition Coach - Black Belt
Multiple-time IBJJF champion with a focus on competitive training.
We offer a variety of classes for all skill levels, from beginners to advanced practitioners. Join us at a time that works for your schedule!
Invest in your health, fitness, and self-defense skills with our flexible membership options. Join our community today and start your Jiu-Jitsu journey!
Perfect for beginners looking to start their Jiu-Jitsu journey.
Our most popular option with full access to all classes and amenities.
Hear from our community about how training at our academy has impacted their lives.
Have questions or ready to start your Jiu-Jitsu journey? Get in touch with us today!
Train together as a family with our comprehensive package.
"CrossFit Arsenal - More Than Just a Gym, It's Family! ⭐⭐⭐⭐⭐ From the moment I arrived in the US, joining CrossFit Arsenal in Watertown was one of the best decisions I made. It instantly became my home away from home, and I've thoroughly enjoyed every single aspect of my time here. The classes are well-coached and engaging, pushing me to new limits while always ensuring proper form and safety. Beyond the daily WODs, the specialized seminars offered invaluable opportunities to deepen skills and knowledge. CrossFit Arsenal is so much more than just fitness. The parties and social events were always a blast, a testament to the incredible community here. The crowd is genuinely fantastic – supportive, encouraging, and full of wonderful people from all walks of life. This isn't just a gym; it's an Arsenal family, and I'll carry a piece of it with me always. Highly, highly recommend!"
"When I was looking to join a new gym nearby, I relied heavily on Google reviews to learn about this place. Now, after a year of training here, I can absolutely confirm what everyone said - the community here is incredible! The coaches are knowledgeable and supportive, the space is well-equipped, and they regularly host events that bring everyone together. I've joined their BJJ classes too, which maintain that same amazing community vibe. Would recommend to anyone looking to start their fitness journey. P. S. This photo is from a recent weightlifting seminar!"
"Arsenal has been an awesome place for fitness and camaraderie. Solid facility, friendly and knowledgeable coaches, and a great community. Highly recommend if you’re looking for place to check out or continue on your CrossFit or Jiu Jitsu journey!"
"CrossFit Arsenal has been home gym for close to a decade now. I lost a bit of weight here while getting stronger, faster, and more importantly, healthier. It’s a great place to be if that is also your goal. This gym is set up with multiple CrossFit classes if you don’t what to do with programming or workout. A lot of people do come in to do their own workout too. Pictures included a picture of us learning about Olympic Weight Lifting."
39 Clarendon St, Watertown, MA 02472, USA
Mon-Fri: 6:00 AM - 9:00 PM
Sat: 9:00 AM - 2:00 PM
Sun: 10:00 AM - 12:00 PM
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