Erik Castiglione - Head Coach/Owner


A native of West Hartford, Erik has had a lifelong passion for fitness. He was a member of the Duffy Elementary School Runners Club and early morning gym, and participated in a number of youth sports throughout elementary and middle school. While attending Conard High School he focused on football, wrestling, and baseball. He graduated in 2005 as a CT scholar athlete and a captain of the CCC West Champion wrestling team. He was first introduced to CrossFit in the spring of 2005, and started cherry-picking WODs shortly thereafter.

After obtaining his BS in electrical engineering from Yale University, Erik became one of the first members of CrossFit Relentless. He moved to Philly in early 2010 to work for the Navy as an electrical engineer and earn his MSEE from Villanova. While in Philly, he began competing in local CrossFit competitions, and became a part time CrossFit coach.

After a few years with the Navy, Erik was able to turn his love of science from engineering to exercise science and physiology, and became a full time coach. He became part owner of two boxes down there, and continued to hone his knowledge and coaching ability.  In 2015, he became Philly’s first CrossFit Level 3 coach.  He moved back home to West Hartford in early 2016, where he is now the owner and head coach at CrossFit Relentless, and seeks to help people of all athletic backgrounds and abilities improve through intelligent program design and top notch coaching.

CrossFit Level 3
USAW Level 2 – Advanced Sports Performance Coach
CrossFit Movement and Mobility
CrossFit Powerlifting
CrossFit Kids
North American Strongman Amateur Competitor
Hybrid Athletics Strongman (now known as CrossFit Strongman)

CrossFit Level 2
CrossFit Level 1
USAW Level 1 – Sports Performance Coach

Shannon Santos - Coach


22 years old, Born and raised outside of Springfield, MA I’ve always been social and I’ve always been involved with sports. From youth soccer, youth lacrosse, youth swimming, later transitioning to 4 year, 3 season high school varsity sports of Swimming, Volleyball, and Track & Field. I always found that I was built differently, stronger than most other girls on the teams without even trying. But I never put that strength to good use.

After graduating high school I became a typical gym rat. 7 days a week at your local globo gym doing whatever seemed to be right getting minimal results. I had always been strong but I had never been trained how to use my strength properly. That all changed the day I did my first WOD at my first CrossFit gym. I was instantly hooked. It was the perfect social outlet, interacting with other people in the class, getting the best workouts I’ve ever gotten, and moving a barbell like it was a second nature. I had found my niche. Less than a year into my CrossFit journey my coach at the time suggested that I get certified to become a coach, I passed my certification and began to learn under him, later taking over for him when he moved away.
As my time coaching and doing CrossFit continued, I discovered my love for the barbell movements. Specifically the Olympic lifts. I later went for my USAW sports performance coaching certification becoming more educated in the sport of Olympic lifting. Doing multiple Olympic lifting meets and even placing at most of them in either 1st or 2nd place.

I don’t know where I would be now without my CrossFit journey. CrossFit has taught me so much about myself as an athlete and a person and it has even given me a direction of where I want to take my professional career outside of the gym.

After 2 years of coaching and a total of 3 years of doing CrossFit have found through that I love helping people. I love the idea of changing lives through health and fitness. I am currently in school getting my associates degree in allied health science with a focus on medical assisting. Once that is complete I plan on going for my bachelors in science in Nursing and then further down the road my masters.

I strive to make connections with our members and to make their hour of working out in the class the best hour of their day.

USAW Level 1 Sports Performance Coach
CPR/ First Aid certified

More Coach Bios Coming Soon!

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