Darren is the owner and founder of ESTLR CrossFit, which became his focus after decades spent in the gym doing everything from bodybuilding, to calisthenics, to powerlifting, to Olympic weightlifting. Since founding ESTLR in 2013, CrossFit has become his lifestyle. He believes strongly in the high-intensity style of training and thrives off the incredible relationships created through CrossFit classes. His passion is to coach others to improve their technique and push themselves to be better versions of themselves. He has 30+ years of experience in coaching and his ultimate goal is to see his gym change lives for the better.
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Certifications:
CrossFit Trainer (CF-L2)
CrossFit Scaling Course Certified
Crossfit Judge
USAW Club Coach
USAW Certified Referee
USADA Certified
Safe Sport Certified

Campbell has been working in Strength and Conditioning since 2018, after serving 10 years in Texas State Prison. During his time in prison, Campbell realized that there was much about himself he did not like; however, training showed him that he could change if he set an intention and put in the work. This led him down the rabbit hole of pysiological adaptation, but he eventually realized that real personal growth calls for psychological and spiritual adaptation as well.

Initially, he began his work as a strength and conditioning coach for purely selfish reasons: he wanted to pursue his passion and spend most of his day in the gym. However, before long, he discovered a passion for helping others. In his coaching, he observed that everyone shines a light into the world that they do not realize they’re emitting. Campbell has found that the most rewarding and effective coaching consists of mirroring that light back to others. This creates self-belief, which allows people to unlock their true strength and potential. His values are: Empowering others, personal growth, and integrity.

As a dedicated CrossFit Level 3 (CCFT) Coach, I bring years of hands-on experience helping athletes of all backgrounds unlock their full potential through structured, sustainable, and results-driven training. With a deep understanding of movement mechanics, energy systems, and long-term athletic development, my coaching approach blends technical precision with a genuine commitment to each athlete’s personal goals.

I specialize in creating training environments where beginners feel supported, seasoned athletes feel challenged, and everyone is empowered to push beyond perceived limits. Whether guiding someone through their first functional movement progression or refining advanced Olympic lifting technique, I prioritize safety, efficiency, and intentional movement patterns.

My experience includes coaching in high-volume CrossFit affiliates, developing individualized programs, mentoring new coaches, and leading specialty courses focused on strength development, mobility, and competitive preparation. I’ve helped athletes improve performance across all ten general physical skills, rehabilitate movement patterns, and prepare for competitions ranging from local throwdowns to advanced qualifiers.

What drives me most is seeing consistent progress—building resilient, confident athletes who move better, feel stronger, and understand the “why” behind their training. My philosophy is simple: coach with purpose, educate with clarity, and create an atmosphere where athletes can thrive both inside and outside the gym.

Whether you’re looking to enhance your foundational fitness, chase PRs, or take your competitive edge to the next level, I’m committed to delivering coaching that is professional, personalized, and rooted in proven methodology.