Meet Your Team

Seth Lingafeldt

Owner & Head Coach

North Carolina born and raised, I came to Charlotte in 2008 to attend the University of North Carolina at Charlotte and pursue an Economics degree. Entering University with hopes to be a stockbroker, and with no athletic background, I had no inclination that my career path would differ so drastically from what I grew up thinking I would pursue.

After a few years of “bodybuilding”, for lack of a better term, my roommate and I found CrossFit Football in the Spring of 2010. It was not love at first burpee.  While I have many wonderful stories and memories of this time, I would rather recount them in person than to bore you with writing.

We joined an affiliate in the Fall of 2010 and I decided that I was not going to be willing pursue a “desk job” upon completion of my degree. I obtained my CrossFit Level 1 certification in October of 2010, and began to pursue coaching as a means toward one day owning my own CrossFit gym. Four years later of studious observations of great coaches, multiple other certifications, and applying my studies of Economics to the strength and conditioning scene, I am beginning a new journey to complete the dream that I began back in the fitness center of my University.

I began coaching comprehensively in the winter of 2010 in the Charlotte area. I have trained personally with CrossFit Games athletes and have competed alongside many in the past. I have coached all varieties of individuals; from a 400+ lb man, a 60 year old woman, collegiate and professional athletes, to 14 year old high schoolers.

My Vision

I am passionate about creating a space that will allow people of all ideals and backgrounds to reach their health and fitness goals, and I am confident that I have the tools and knowledge to help everyone who walks through the doors of GrowStrong CrossFit to achieve more than they think is attainable. I do not care what brings people to the gym, whether it is to build muscle, lose fat, to look good in the mirror, because their friends are involved, or because they want to take control of their life – all I care is that you enter the door.

I am confident that the training methods we use are the most superior and effective methods to create an efficient and powerful human body. Because of the community that we foster at GrowStrong CrossFit, we fully expect everyone to find friends and a family with people that are all on the same fitness journey as they are. Never in this gym will anyone have reached a destination – and forever will we encourage all members to strive for something greater.


  • Level 1 CrossFit Trainer
  • CrossFit Football Certified Trainer
  • USAW Certified Sports Performance Coach
  • CrossFit Mobility Trainer

Brett Thornton


I’m a North Carolina native, Air Force veteran and graduate of the University of North Carolina at Charlotte, (studied psychology and philosophy). I’ve trained extensively in various internal and external martial art styles since I was a child. However, I did not become serious (and passionate) about my health and fitness until after my father passed away in 1999. It was then that I had the full realization that my dad had died abruptly of a massive heart attack, my uncle and both grandfathers also died of heart attacks way too early in their lives. My family’s risk of heart disease is severe. My risk is real! As a result, I dedicated myself to a life of healthy nutrition and fitness. I dug in deeply to my martial arts training.

Along with my martial arts conditioning, I began doing P90X and Insanity in my garage gym (don’t laugh – both are very legitimate fitness programs and prepared me well for what was to come). I received my P90X and Insanity group instructor certifications and began co-coaching live classes at fit clubs. I very much enjoyed sharing the value of these programs and teaching people about basic fitness and nutrition, but I knew that I was ready for the next level. I was ready for a serious athletic training environment.

Concurrently, some family friends of mine kept telling me that I should try CrossFit, and how much I would love it. In April of 2014, (after more than a year of hearing about this), I finally gave in and decided to appease my cherished CrossFit fanatic friends (so they’d stop yammering about it). I attended a free community workout. I was literally floored!!! The 9 minute workout consisting of burpees, kettlebell swings and wall ball throws severely kicked my ass (and I thought that I was very fit). I was immediately and intensely hooked!!! I found every aspect of CrossFit to be electric and exceptionally challenging! What struck me most were the knowledge, skill, caring and depth of the coaches alongside the high-energy community support and friendly competitiveness of each athlete. I thought to myself, “This is different. This is real. This is superior! This is something that everyone can benefit from”!  I’ve never looked back!

My Vision

I believe in surrounding yourself with genuine people who push you to grow mentally, spiritually and physically stronger; in essence, to become a better human being. One of the best places to do that is with a CrossFit family and community. Although, I’m still (and always will be) on my CrossFit journey, I’ve apprehended the massive positive effect that CrossFit has had on every aspect of my life. The value of any experience is found on the road you travel. There’s a tremendous education in all of the bumps and curves along that path. With an open mind and heart, every day has the potential to be an opportunity for progression. It’s a privilege for me to co-own GrowStrong CrossFit. It provides me the ability to share what I’ve seen so powerfully at work in my own life and what I deem as priceless truths: Movement is vitality and abundance. Age is just a number. Believe in yourself and anything can be accomplished. Empower and uplift others through community. Maintain honest commitment to physical, mental and spiritual growth. These truths are universal in applicability. Longevity and fulfillment in life are the result.

It’s my desire to provide a first-class training facility where you will feel at home and safe. Our accomplished and dedicated coaches are committed to helping you achieve your unique health and fitness goals. With an emphasis on safety, technique and skill, our coaching staff will assist you in unlocking your latent potential. This is an open place where everyone who has the desire and dedication can GrowStrong!


  • Level 1 CrossFit Trainer
  • CrossFit Mobility Trainer
  • Shorinji Toraken Ryu Kempo Karate – Shodan, Black Belt
  • Yang Style – Embrace the Moon – Tajiquan Level One Instructor
  • Usui Shiki Ryoho – First Degree Reiki Certification