Hi, I’m John DeRosia.

I grew up around woodworking and construction, then started working out on my own in my bedroom at 14. Over a decade later, those two parts of my life have grown into ThatWoodGym.

I’ve always liked the freedom of training at home. No waiting for equipment or planning around gym hours. Just my music, my space, and the freedom to train my way.

Building my own equipment let me take that further, creating a gym around the space I had and the way I wanted to train.

Now I help others build a gym that fits their space, their training, and their life.

The Builder Behind thatwoodgym

Mission

Help more people find their own way to pursue their fitness goals.

ThatWoodGym brings together custom woodworking and personal training to help people see what’s possible and find a starting point that works for them.

Through thoughtfully built equipment, creative use of space, and training shaped around the individual, I want to give people more options to make fitness part of their lives. For some, that means bringing an idea for their home gym to life. For others, it means having the guidance and support to begin or take on a new challenge.

My goal is to help you find what works for you—and build the confidence to keep going.

Philosophy

Start with what you have. Build from there.

I believe a gym and the training that happens in it should reflect the individual. Your goals, your experience, and your sense of style all matter in creating a space you enjoy and an approach to fitness you can make your own.

To me, custom equipment is a blend of function and art. Wood’s versatility allows each piece to take on its own character through its design, color, and finish—shaped by the person it’s built for.

Whether we’re bringing an idea to life or working toward a fitness goal, my approach is the same: find a place to begin, make each step purposeful, and let what we learn guide what comes next.

Built with wood

I grew up around woodworking and construction. My dad and grandfather both owned kitchen and bathroom remodeling companies, where thoughtful cabinetry could make every inch count. I bring that same approach to home gyms: finding creative ways to store equipment while leaving room to train.

They taught me the value of hard work and the satisfaction of building something yourself. I grew up surrounded by things my family made—including the house I now call home, built by my Papa in 1985.

That upbringing shaped how I approach an idea: start with what you have, learn as you go, and put in the work to bring it to life.

2006

My dad and me on the left, and my Papa holding my older brother, during construction of their workshop. Twenty years later, I’m starting ThatWoodGym in that same pole barn.

At 14, I started training in my bedroom with nothing but a doorframe pull-up bar. I challenged myself to work out for 60 days straight. Seeing all the progress I was able to make in those first two months made me wonder: what would be possible if I kept at it?

Sixty days became a year, then a year became a decade.

I learned to hold myself accountable and adapt my training as my goals changed. Each new goal gave me something to chase, a different challenge to work through, and a chance to get creative with my workouts.

Whether an approach worked or needed adjusting, I learned something I could carry into the next challenge. Over ten years, those lessons have kept bringing me back to the same idea: start, stick with it, and learn along the way.

Built through fitness

The Original Wood Gym

2017

Started as an American Ninja Warrior inspired cliff hanger obstacle with monkey bars

2020

Wanted to get into weight lifting so I added a rack

2024

Cleaned it up with a fresh coat of paint

The more I learned through training, the more I wanted to understand the science behind it. That led me to Michigan State University, where I earned a degree in Kinesiology with a minor in Health Promotion.

During my personal training internship at State of Fitness, I put that knowledge into practice and discovered how much I enjoyed helping others chase their goals. After graduation, I earned my NASM-CPT certification and took on my first client: my mom.

She had never worked out before, but she wanted to do a pull-up. After 206 days of showing up through the ups and downs, she did it. Now, after more than a year of consistent training, she has the confidence to chase new goals—including running her first 5K.

Seeing her progress showed me how much it meant to help someone else discover what they’re capable of.

Built through knowledge

Built by Hand

Building has always been part of my life.

Growing up around woodworking showed me how versatile wood could be. I thought, if we can build houses with it, why couldn’t I use it to build my own gym equipment?

After graduating from Michigan State, I returned home to Ann Arbor and took a job framing houses for Prestige Builders while I studied for my CPT exam. I wanted to keep doing what I loved—working with my hands—while learning practical skills I could carry into my own projects.

I’ve always enjoyed taking an idea in my head and figuring out how to make it real. So I started building my own gym equipment—racks, benches, storage, and other pieces designed around my space and the way I wanted to train.

The more I built, the more I realized I could bring together the two things I cared about most: fitness and building.

That became the foundation for ThatWoodGym.