KBX Instructors

Marshell Davis – Head Instructor –

instructor_templateAside from being a former US Army Ranger for 6 years, Marshell has an extensive background in the Martial Arts and fitness training. With over 35 years of experience in different styles from Ninjitsu, Western Boxing, American Kickboxing, Muay Thai, BuKyok Ayu, Shidokan Karate, Brazilian Jiu-Jitsu and more. He has trained with legends such as Master Ricardo Murgel, and world champion fighters Manu Ntoh and Richard Trammell. He is also an experienced competitor himself with over 30 boxing and kickboxing matches and was the 2001 Golden Glove Champion as well as the 2002 GK Kickboxing Champion. Marshell has also competed in Body-Building and Power Lifting. Being a certified fitness and martial arts instructor for over 15 years, Marshell has helped many people achieve their fitness goals as well as trained fighters like 4 time World Champion Kickboxer Trisha Hill. If you want the best quality training, whether it be for competitive sports, taking your training to the next level, or just to get
back into shape, Marshell can get you where you want to be!

Having been trained in boxing by his father since Marshell was a young child, his father instilled in him a few key principles that he still adheres to today.  First, as long as one perseveres and adopts an indomitable work-ethic, living a fit and strong life is always a possibility one can achieve and never outgrow.  Second, his father used to say: “Master the basic and you’ll master boxing”. So, in every field or sport Marshell delved into, he made sure he persevered and had the basics deeply rooted in him. Equipped with these homegrown philosophies, He found intrinsic value in providing practical fitness-goals to everyday individuals who just want to live healthy lives. With these two simple philosophies: persevering and mastering the basic–he strongly believes fitness is not just for the elite athlete. Fitness is now a gift we give ourselves and could be enjoyed by anyone.

Heike Gurley –


Discipline: Krav Maga, Personal Training & Bodybuilding
Heike is a one of a kind personal trainer as well as the second female to be certified as a Krav Maga instructor through the United States instructor program. She has been Kickboxing and Boxing under Marshell Davis since 2005. She is also been a highly accomplished amateur bodybuilder and has reached pro status. Her accomplishments in Bodybuilding include the following:
*1st place winner in novice @ Snbf Georgia Fame
*1st place winner in open @ Snbf Fame
*1st place winner in overall @ Snbf Fame
*Best poser @ Snbf Fame
*1st place open short @ Capital Classic
*1st place open short @ Southern Open Snbf
*1st place overall @ Southern Open Snbf
*2nd place open short @ Snbf Nationals

in 2013 Heike received her Level 1 CrossFit certificate.
With one look at Heike, you can see that she practices what she preaches and is more than eager to bring success to her clients.

Grace Thames –

Discipline: Krav Maga
Grace Thames started her Krav Maga training in November of 2007 and was hooked after her first class. From that point forward she trained everyday classes were available. Her passion for Krav Maga continued and in August of 2008 she attended the Phase A Instructor Certification course through the Krav Maga Worldwide headquarters in Los Angeles, California.

She began teaching and training at KBX Gym in 2009 and the Krav Maga Alliance affiliation. In August 2015, she earned her Black Belt under John Whitman at the Krav Maga Alliance headquarters in Culver City, California.

In addition to her Krav Maga technical training, she trained in Krav Maga fitness classes utilizing kettebell and cross training workouts.

She also has her Level 1 CrossFit certification. Today, she varies her training between Krav Maga, cross training, cardio kickboxing and boxing while working full time and spending time with her family.

Chad Armstrong –

kbx_instruct_chad22-1 in Shidokan, 3-1 in MMA, 12-4 in Kickboxing/Muay Thai
2004 WKA Junior Winner
2004 WKA Adult Semi-Finalist
Trained under Kelly Leo for 13 years.
Trained in boxing, Muay Thai, and Shidokan Karate

From Dahlonega, GA



Lissa Keppner –

kbx_instruct_lissa_kAs a certified Massage Therapist, Lissa had strong focus on health and fitness before she started training at KBX in Kickboxing in 2005. Now, she is not only an experienced fitness instructor and personal trainer, but a competitive athlete as well. She competed in her first kickboxing match in 2006 and has fought over 20 times in all different styles from Muay thai,​I​nternational rules and American Kickboxing. She has also competed in knockdown karate, mixed martial arts and Boxing.

After retiring due to health issues in May 2009, she went on to compete in powerlifting for 2 years and placed 4th in the Open Women’s Equipped division at the national level under the USAPL. She made a short comeback into the boxing venue in 2012, but again, was forced to retire due to health issues.

Lissa started her career in fitness with KBX Gym and has been teaching kickboxing and other fitness classes since. She relocated permanently to Athens, GA in 2013 where she and her husband now run their own boxing facility. Lissa also currently teaches Kickboxing classes for the University of Georgia at the Ramsey fitness center. She is pleased to be able to continue teaching classes in Alpharetta on Fridays for her KBX family!

Michelle Casto – bootcamp_icon6

Michelle has always enjoyed an active lifestyle. She started early in her youth as a competitive swimmer and continued until she enrolled at the University of North Carolina at Charlotte where she discovered a love for weight training and aerobic style physical activity. She spent the next few years searching for her place in the fitness industry. She found her first inspiration when she began the Body for Life Challenge in 2007 which sparked not only her desire to be healthier but to also share this passion with others. Following her newly discovered passion, in 2009 Michelle received her certification through the Aquatic Education Association (AEA) and became a water fitness instructor. Wanting to diversify her experience, she then became a licensed Zumba instructor and also received her group fitness certification through The American Council on Exercise (ACE).

In 2012 she received her Level 1 Certificate for CrossFit and also her CrossFit Mobility Certificate. She has been a CrossFit Coach and has instructed boot camp at parks, at CrossFit and now, at KBX Gym. She is currently pursuing a certification in nutrition and hopes to receive a certification through USA Weightlifting in 2016.

Dan Kelly – Krav Maga

Dan has over 8 years of experience in Martial Arts. He is a 1st degree black belt in Taekwondo and has been training in Krav Maga (Worldwide and Alliance) for over 4 years. He is currently Level 3 and is a certified Krav Alliance Level 1 instructor.

Dan was drawn to Krav Maga because of it’s instinct-based, aggressive, and practical approach to self defense and fighting. He is passionate about learning and demonstrating proper Krav Maga techniques.

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