

Redefining the aging process, one workout at a time!
We provide you with the tools and support you need to build confidence, gain strength and create healthy habits that support a long and active life.
A Community that will keep you going
We know it can be intimidating to get started on a new fitness journey (we’ve all been there at one point!). Our aim is to make sure your journey starts as fun and stress-free as possible.
Our training staff are passionate about you and your fitness goals.ย We provide top-notch and attentive coaching. Our workouts are constantly varied making sure you are always challenged and never bored.ย We show you how to move safely and seamlessly scale movements to your ability.ย This helps build up your skills in a safe manner, especially if you are new to CrossFit or any fitness routine.
If you are ready to take action and invest in a healthier you, call or come see us at CrossFit Underdog Union. We provide workouts for all abilities, expert coaching, a fun, supportive environment and offer 1×1 nutrition coaching services. It is everything that you need to crush your goals!!

Group Crossfit Classes
Nutrition Coaching
Personal Training

Constantly Varied
You won’t get comfortable. Our workouts are always changing!

EXPERT COACHES
Our coaches have what we call the G.A.F.F. Itโs the Give a F*&K
Factor. We care.

AMAZING COMMUNITY
ย The friendships and community are just as important as the workouts! Come be part of a community that feels like family.
Nutrition Coaching
We believe something as fundamental as nutrition, shouldnโt be complicated. Which is why we use a comprehensive habit-based approach to nutrition and an enormous supply of resources to keep you on track!

Happening Now at CUU
Adaptive Fitness is HERE! We are Partners of the Special Olympics of CT



New to CrossFit?
EXCELLENT Based on 18 reviews Lisa Lieder2025-04-09Trustindex verifies that the original source of the review is Google. I was a little afraid to start CrossFit because I couldnโt even do a sit-up. CUU is full of supportive partners who make you feel like you can do anything given time and consistency. Now I amaze myself every class. Jennifer Reynolds2025-04-07Trustindex verifies that the original source of the review is Google. Great gym, great training, great exercise experiences. From the trainers to the classes, it's a challenge but fun. You can tailor it to any fitness level. Amy, the owner, is full of contagious energy. Supportive members. Just a fantastic experience. Highly recommend Aimie Granger2025-04-05Trustindex verifies that the original source of the review is Google. Clean, top of the line equipment. Abundance of class times. Welcoming and friendly community. Melissa Hoyt2025-02-02Trustindex verifies that the original source of the review is Google. Crossfit Underdog Union has become my home away from home. The owner, coaches, and members are supportive, inspiring, empathetic, encouraging, and sincere! From day one, I felt like I belonged. Getting fit and strong are just a bonus to gaining friends who feel like family. Thank you CUU for providing a welcoming environment where everyone feels at home. Sherilynn Latour2024-12-24Trustindex verifies that the original source of the review is Google. I absolutely โค๏ธ this gym and Amy! Butt kickings made fun ๐คฉ Duane Barnes2024-12-03Trustindex verifies that the original source of the review is Google. CrossFit Underdog Union is hands down one of the best fitness communities I've ever been a part of! From the moment you walk in, you feel the energy and positivity in the room. Coach Amy, who is also the owner, is absolutely phenomenal. Her knowledge, enthusiasm, and passion for fitness shine through in every class. Amy creates an environment that is both challenging and incredibly fun. She knows how to push you to your limits while making sure you're safe and confident in every movement. Whether you're a seasoned athlete or new to CrossFit, youโll feel supported and motivated. The community here is fantastic tooโwelcoming, encouraging, and full of great vibes. Every class feels like a mini party with plenty of sweat and laughs. If you're looking for a place to crush your fitness goals and have a blast while doing it, CrossFit Underdog Union is it! Highly recommend to anyone ready to take their fitness to the next level. Trisha Wilber2024-12-01Trustindex verifies that the original source of the review is Google. 5 Stars - An Amazing Gym Experience! Iโm so thankful to have found CrossFit Underdog Union! From the moment I walked in, I felt welcomed and supported by everyone โ both coaches and members alike. The members are friendly, encouraging, and truly make it a community. The coaches are fantastic โ knowledgeable, approachable, and always willing to help you improve. They push you to do your best while also ensuring you're training safely and effectively. If youโre looking for a place that feels like family and challenges you to grow, CrossFit Underdog Union is the place to be. Highly recommend! Debra Amato2024-07-10Trustindex verifies that the original source of the review is Google. I Love going to CrossFit underdog Amy the coach is very accommodating patient and an excellent coach on showing you how to do things that you donโt know sheโs very supportive positive uplifting and fun. I always have a great time even if Iโm working really hard. Lisa Cote2024-06-26Trustindex verifies that the original source of the review is Google. Coach Amy is amazing and highly recommended this gym.