David’s interest in developing athletes can be traced back to his experience as a football and track athlete in high school and in college where he was active in football and boxing. He received a football scholarship to Valparaiso University where he played both cornerback and quarterback. It was there that he discovered his true passion and talent for facilitating athletic development and made the decision to transfer to Iowa State University. While at ISU playing quarterback, he became the assistant strength coach under Steve Ballanger. David received his degree in Exercise and Sport Science with a minor in coaching.
David has since founded two highly specialized performance enhancement facilities and has become a member of the United States Weight Lifting Association and The National Strength and Conditioning Association. He has held certifications as a Strength and Conditioning Specialist, Sports Performance Coach, Performance Enhancement Specialist and as a Youth Fitness Specialist for over 15 years.
David has worked with athletes of all developmental ages and levels. From his experience, knowledge, and passion, he has developed a unique protocol for Athletic Development through years of research and refined training techniques. This protocol continues to show amazing results in each individual, giving each athlete the ability to achieve levels of performance they thought were unattainable. David currently resides in Waxhaw, NC with his wife, Justine and four children: Dawson, Jacob, Faith and Noah.
As a high school athlete, Ike won four state championships for the Charlotte Country Day Varsity Boy’s Tennis Team from 2000-2003. After high school, Ike went to play tennis for Clemson University where he had the second best winning percentage in school history. Ike also held the number one position for singles as well as doubles. Ike played in the 2007 NCAA All-American Qualifier and in 2009 was named captain of the Clemson Varsity Tennis team.
In 2009, Ike played three years on the Pro Future Tour throughout Europe and the United States. During this time Ike trained extensively with David and reached new levels of conditioning and performance.
After touring Ike took a job with Octagon in the field of sports marketing and started his professional career. At Octagon Ike realized that his true passion was in the proper training and development of athletes. Using his never ending energy and enthusiasm, Ike draws from his experiences in training and sports marketing to make other athletes aware of the possibilities they have in reaching their full potential. Ike currently resides in Charlotte, NC.
Ashley Heiligenstadt, CSCS
Director of Operations
Ashley Heiligenstadt received her Bachelor of Science degree from James Madison University in Kinesiology. Ashley concentrated her studies in Exercise Sciences and Pre-Physical Therapy.
While at James Madison, Ashley worked at the Morrison Bruce Center developing programs for women and girls promoting an active and healthy lifestyle. She also served as a Sports and Fitness Coordinator for the Overcoming Barriers program focusing on motor skills development for children with disabilities.
Following an internship at USPC, Ashley was offered a position as a Strength and Conditioning Coach. Ashley oversees all the day to day operations at USPC along with athletic assessments and baseline testing for all new members. Originally from Forest, VA, Ashley currently resides in Charlotte, NC with her husband Erik.
Jeffrey Hill, MS, USAW
Director of Athletic and Sport Performance (Main Campus)
Jeffrey Hill received his Master of Sciences degree from Appalachian State University in Exercise Science with a concentration in Strength and Conditioning. While attending Appalachian State, Jeff worked as the Women’s Rugby Head Strength Coach. During those two years; the team was 2013 and 2014 Ruckotberfest champions, two players were selected to the US All-American Team, and one player even represented the US national 7’s team. Prior to Graduate School Jeff received his Bachelor of Science degree in Exercise Science from the University of North Carolina – Wilmington.
In 2014 and 2015 Jeff worked as the UNCW Men’s Rugby Head Strength Coach. Upon implementing his own protocol, UNCW finished as runner-up SOCON champions and SOCON champions in back to back seasons. Even more important, the team experienced zero non-contact injuries, and a decrease in overall injuries.
Following an internship at USPC, Jeff was offered a position as a Strength and Conditioning Coach. His education and USA Weightlifting certification have provided him with an understanding of the theory and thought process that go into developing successful strength and conditioning programs. Originally from Rocky Mt, NC, Jeff currently resides in Charlotte, NC.
Nathan Berggrun, MS, ATC, LAT, CSCS
Director of Human Performance
Nathan Berggrun received his Master of Science degree from the University of Tennessee in Kinesiology specializing in Sport Psychology and Motor Behavior. He received his Bachelor of Science degree from the University of North Carolina at Charlotte. While attending UNCC, Nathan was an athletic training student for many different athletic departments such as Davidson College, Johnson C. Smith and J.M. Robinson High School.
After graduating from the University of Tennessee, Nathan worked at The Rush, in Asheville, where he worked with athletes and general fitness clientele. Nathan also created the Strength and Conditioning program for the Asheville Racquet Club.
During his time at USPC Nathan has worked closely with athletes in Injury Prevention and Expedited Recovery. His experience in the field of athletic training allows him to properly identify many underlying causes of injury. Originally from Asheville, NC, Nathan currently resides in NC with his wife Stephenie.
Director of Speed and Agility
Omar Ray received his Bachelor of Science degree from Wingate University. Omar played Wide Receiver for the A.L. Brown High School football team, and participate in the 400m sprint for the track team.
While attending Wingate University, Omar participated in the 200m, 400m, 800m sprint events and participated on 4x400m relay team. In the summer of 2015 Omar returned to A.L. Brown to assist in the weight room as well as on the field for speed and agility.
Omar currently resides in Charlotte, NC.
Jennifer (VanAssen) Brunelli, MS, RD, LDN
Director of Nutrition and Wellness
Jennifer (VanAssen) Brunelli received her Masters in Human Nutrition from Winthrop University in Rock Hill, SC. She received her Bachelor of Arts degree from the University of South Carolina in Marketing and Management. While attending the University of South Carolina, Jennifer was a 7-time All American swimmer for the Gamecocks. Jennifer was also National Champion runner-up in the 100 and 200 freestyles at the 2004 NCAA Division 1 Championships. She competed in the 2004 Olympic Trials in the 50, 100, and 200 frees and was named the 2004 University of South Carolina’s Female Student Athlete of the Year. She later went on to Arizona State University where she earned a degree in Dietetics.
Jennifer’s passion for nutrition education started in the 2000’s which lead her to open RDpro, LLC, a Nutrition Consulting business in the Charlotte, NC in July of 2011. She has worked to educate her clients about nutrition education, meal planning, body composition assessments, eating disorders, food intolerances and allergies, performance kitchen design, and supplement analysis. Jennifer has experience working with a wide range of clientele including: former and current collegiate/amateur athletes, professional athletes, and other motivated individuals looking to find an edge. In the past, Jennifer worked for NC State University as the Director of Sports Nutrition and currently works for the Carolina Panthers, as the team’s Sports Dietitian. In 2016, Jennifer received a BOB award from Charlotte magazine for the Best Dietitian in Charlotte.
Originally from New Jersey, Jennifer and her husband Nicholas currently reside in Charlotte, NC with their two children, daughter Sloane and son Nathan.
Cannon received his Bachelor of Science degree from East Carolina University in Exercise Physiology. While attending East Carolina, Cannon worked in the Biomechanics Laboratory studying bio mechanical plasticity and gait locomotion. While working in the Biomechanics Lab at ECU, Cannon helped market and operate the first ever National Biomechanics Day, a national event educating youth about biomechanics.
Following an internship at the United States Performance Center, Cannon was offered a position as a Strength and Conditioning Coach. Cannon has a passion for athletic development, performance training and building relationships with athletes. While working at USPC, Cannon is continuing his education by actively pursuing his Certified Strength and Condition Specialist.
Originally from Orlando, FL, Cannon currently resides in Charlotte, NC.
Melissa Vriner, CSCS, CPT
Melissa Vriner received her Bachelor of Science degree from the University of Delaware in Exercise Science. In 1999, Melissa was an U.S. Collegiate Champion and U.S. Championship competitor. Prior to moving to the Carolinas, Melissa competed as a professional Figure Skater for eight years.
In 2011, she was hired to assist with the figure skating strength and conditioning program at the Extreme Ice Center. Melissa received the 2014 PSA Peter Kollen Sports Science Award and the USOC Doc Counsilman Sports Science Award for her work within the figure skating community. She is also part of the U.S. Figure Skating Sports Science and Medicine Committee.
Originally from Denver, CO, Melissa currently resides in Fort Mill, SC with her husband Luke and daughter Sloane.
Alissa Castellon, CSCS
Alissa Castellon received her Bachelor of Science degree in Exercise Science from the University of North Carolina – Wilmington. Throughout high school, Alissa danced for the Greensboro Ballet Company. While attending UNCW, Alissa’s passion for dance continued as she participated in several different dance clubs.
After receiving her degree, Alissa completed her CSCS certification and interned at multiple reputable strength and conditioning facilities. While interning at these prestigious performance centers, she was able to gain the experience that allowed her to assist athletes in gaining strength, speed, power, agility, and flexibility. Alissa has experience training athletes with a wide range of skill sets and abilities.
Alissa’s passion for training athletes started early while training as a ballet dancer and struggling with constant injuries. Alissa strives to help keep athletes healthy and strong so they are able to continue to compete in the sport that they love. Originally from Saugerties, NY, Alissa currently resides in Charlotte, NC.
Logan Heck, CSCS
Logan received his Bachelor of Science degree in Exercise Science from the University of North Carolina-Chapel Hill. A former NC high school state champion in the 50 and 100-yard freestyle, Logan swam all four years at UNC where he was an NCAA All-American. He also qualified for the 2012 and 2016 U.S. Olympic trials.
Following graduation, Logan completed his CSCS certification and began his professional strength and conditioning career at Fitness Together before being offered a position at USPC.
Being a high school and collegiate athlete, Logan has a true passion for training athletes and helping them reach their full potential. Logan is originally from Boca Raton, FL and currently resides in Charlotte.