Meet the Staff

Here at BGB CrossFit, you’ll ignite your inner fire, fueled by expert instruction and all the physical, mental and nutritional support you’ll need to push forward. Our caring coaching staff and super-inclusive community is comprised of really great people. Whether you’re a newbie or an experienced CrossFitter, our team lives to help you reach for your personal best every single day! You’re going to love it here.

Nathan Black

Owner / Coach / General Manager

About Coach Nathan

Coach Nathan Black has been a CrossFitter for five years and specializes in “a little bit of everything to make lives better.” He considers it a mission to help people “stay out of nursing homes as long as possible while having fun,” and loves seeing our members bond while watching personal records happen and antics ensue.

Active in track and field, high school golf and tennis, beach volleyball, and amateur soccer, Nathan’s professional background is in group training and development. “The combination of teaching in a group setting and the love of seeing people improve their health was a no-brainer for me to be a CrossFit coach and gym owner,” he says.

Nathan’s favorite motivational saying is: You can’t start the next chapter in life if you keep re-reading the last one.” He doesn’t like to dwell on the past because it cannot be changed. “I can learn from it and try not to make the same mistakes or I try to duplicate the victories,” he says. “Also, I have a fascination with making people laugh.” In fact, it’s a constant goal of his, if you haven’t already guessed. When not in the gym, Nathan enjoys hanging out with his family or thinking up new ways to keep our box at its best.

CERTIFICATIONS: CrossFit Level 1, CrossFit Level 2

Dana Black

Owner / Coach

About Coach Dana

Coach Dana Black is also our Nutrition Coach. “I’m passionate about a lot of things,” she says, “but I’d have to say that I’m most passionate about nutrition and using whole foods nutrition for the prevention and treatment of chronic disease and obesity. I love seeing our members always moving forward on their journeys in health and fitness. I love seeing them reach goals, get stronger, change their body composition, and learn new skills. “

A dancer who studied ballet, tap, jazz, and modern dance, Dana loved dancing and wishes she hadn’t stopped. “I tried one season of track in middle school, one season of indoor soccer in high school, and then played three seasons of indoor soccer on a co-ed team in my mid-20s,” she says. “I was not good AT ALL! In high school, I became interested in working out, and took as many classes as our PE department would let me. It was my high school aerobics teacher, Debbie Buckle, whom I can credit for sparking my interest in fitness.”

After graduation, Dana deviated from her athletic path. “During that time, and after the birth of my first daughter, I found myself quite unhealthy and significantly overweight,” she says. “I lost 80 pounds and reignited my love and passion for fitness. I found CrossFit while transitioning back into college to finish my degree. It was through my experiences with my first CrossFit coaches that helped me realize I wanted to coach as well. I wanted to help people get healthy and fit through hard work, dedication, real nutrition, and positive feedback.”

A lover of the arts and museums, Dana is currently studying towards Board Certification in Holistic Nutrition as well as certifications in Nutrition for Weight Management, Sports Nutrition, and Nutrition and Wellness Consultant. She also loves being silly in the gym, especially to cut the tension. in like to break out in random dance moves for no reason, or use a funny reference to help athletes visualize what I’m asking them to do. I will dance and sing ridiculously just before a workout starts in order to break the tension.”

CERTIFICATIONS: CrossFit Level 2 B.S. in Sports and Health Sciences: Exercise Science

Kirsten Guilliams

Owner / Coach 

About Coach Kirsten

I got my start with Crossfit after college. I suffered a hip injury which ended my track and field career my freshman year. After graduation I still really missed the competitive aspect of sport but was unsure of what else I could do. All I ever knew was running, and the globogym left me feeling unmotivated and bored. CrossFit has helped me rehab my hip, get me into the best shape of my life, and find a new passion and career path. Since starting my CrossFit journey 11 years ago, I have been lucky enough to participate in WZA, qualify for Granite Games, and earn my spot as a regionals team athlete 5 times.

My focus in Crossfit centers around helping people improve their biomechanics by restoring their normal movement patterns. As such, I hold certifications in Functional Movement Screening/ Assessments and corrective exercises. I am also a fully licensed massage therapist specializing neuromuscular therapy and sports massage. My sessions include manual therapies in combination with cupping and IASTM.

CERTIFICATIONS: CF L1, LMT, Rocktape cupping/ blades, FMS/FMSA, CPR certified


Derrick Ayers


About Coach Derrick

Coach Derrick Ayers has been CrossFitting for five years and is passionate about learning. “I am a teacher, so I am very passionate about learning new things, and the learning of others,” he says. “I want to know the ‘why’ behind something, and feel that people need to know why things are the way they are. I also believe this applies to movement. If a coach tells an athlete to change something, they both need to understand why I need to change, and how it will benefit the athlete.”

Derrick really enjoys hearing our members’ stories, getting to know who they are and why they are here. We are a community of people from every walk of life who all want to become better versions of ourselves,” he says. “Being a part of this and seeing people become happier about who they are and what they are capable of is the most enjoyable part about coaching,” Growing up, Derrick played baseball, basketball, ran track and played college golf becoming a professional golfer for several years afterward. “During that time, I gave golf lessons to many people, one of whom was a CrossFitter. I asked him what he did because he was really fit, and he told me CrossFit. I then proceeded to look up CrossFit online and tried out some of the workouts.” He was hooked from that point on.

Derrick has three boys and is the Cubmaster for his middle son’s Cub Scout pack. “We have a lot of fun going camping, hiking and fishing with all of the boys from our pack,” he says. “I love being a father trying to show my children how to become healthy, productive members of society.”


Terri Ferguson

Fit Fast Coach

About Coach Terri

My name is Terri Ferguson and I started CrossFit January 2013. Before discovering and falling head over heels in love with Crossfit I was a Zumba instructor. Over the years of Zumba I began to grow bored. Then my husband introduced me to CrossFit. After the second time I tried it I was hooked. I loved having a way to compete with myself everyday and having a group of people around who were always encouraging me to improve. Because of CrossFit I have become stronger, better conditioned, more confident, improved my body composition, and overall become a much healthier person. I am very passionate about helping people improve their health.

Herm Lum


About Coach Herm

Herm was introduced to Crossfit in 2013. He spent over a decade as a Health and PE teacher and helped to develop a curriculum that is currently being used by a school system in the metro Atlanta area. Over the years, Herm has had wonderful experiences coaching middle school, high school, and college athletes and teams.

Rod Sylvester


About Coach Rod

I was born in Montgomery, Alabama but was raised mostly in McDonough, Ga. I had a slight interest in athletics growing up but never considered myself an athlete as I really stopped after 8th grade.

I started my crossfit journey in 2015. I actually stumbled into Crossfit. I was living overseas and was trying to stay active to combat any potential anxiety and/or homesickness. I signed up for a gym membership that was offering free crossfit classes as an early bird special. My first class had pull-ups in the warm up (I couldn’t do pull-ups) and I instantly felt out of my league. I literally bumped into the coach as I was trying to leave and he convinced me to stay and I’ve been hooked ever since. As someone who didn’t play sports growing up, I NEVER thought I’d be able to reach the goals I’ve accomplished with my strength and endurance. My crossfit journey has done so much to promote my mental health and self esteem and I’m forever grateful for the very special friendships I’ve established through it.

It’s an honor to coach people and help them on their individual fitness journeys. It’s such a rewarding process to see people come in everyday and get better, stronger and more confident in themselves. the coaches of BGB have done an amazing job not only with programming, but creating a safe/diverse space where people of all walks of life and fitness levels feel welcome and it’s an honor to now be a part of that team as well.