top of page


Racelab is a family owned business that has been the leading coaching company in the Phoenix area since 2000. Our passion for endurance sports as a way to a healthier and happier lifestyle is based on the positive impact we've seen it have on the lives of our athletes. We strive to help every one of our athletes reach and surpass their goals.

usa team coach.png
Rio Coach Logo.png
usa swimming.png

Bettina Warnholtz

- Team USA Coach

- USA Olympic Coach - Rio 2016 - GOLD Paratriathlon

- USAT Level II - ITU

- USAT Level II - Endurance

- US Masters Swim Coach

With more than 20 years experience, Bettina is the premier Running and Triathlon Coach in Arizona. She is the heart and soul of Racelab and takes pride in each and every one of her athletes and their performance. The task of developing customized training programs for all levels of athletes and to apply the most appropriate coaching techniques to each individual has significantly added to her experience and knowledge. Her passion for the sport and the promotion of fitness at all levels has driven her to not only keep on top of the latest training methods, but also continuously study and learn from sports physiologists, physical therapists, elite athletes, renowned coaches (like Mark Allen & Rodolfo Gomez) and most importantly from each athlete she has coached.


Born in Mexico City, she moved to Germany in 1990 with her family. In 1994 she came to Phoenix where she started her coaching career. By May 2000 she and her husband, Gus, became the owners of Racelab. Around this time she also earned a second degree Black Belt in traditional Japanese Karate.

Her multi-cultural mindset, disciplined approach, and ability to speak three languages fluently has helped her to develop a sensitive and open way of communicating with a diverse group of people, giving her a significant advantage in her coaching career.


She has individually coached thousands of athletes of all levels of experience and ability... First-timers to Professionals and Olympians. Bettina has finished many marathons and triathlons, including Ironman Arizona in 2006 and 2012.  


She is a certified USA Triathlon Coach and one of only coaches in the the US who has earned the ITU Level II AND Endurance Level II Certification.


gustavo Warnholtz

Gus is an Aerospace Engineer and coach with a passion for endurance sports performance. He is married to Bettina, and they have co-owned Racelab since 2000.

Gus has been coaching athletes since 1999. Utilizing his engineering / analytical perspective, he has been able to thoroughly study and simplify the complexities of human athletic performance. He has developed several new protocols and concepts, including a user-friendly heart rate-based training method that has proven to help optimize the time devoted to training.

Since 2000, the experience and data gathered from thousands of endurance athletes trained by Racelab, as well as its analysis by Gus, has allowed Racelab to constantly update and improve the training programs offered. His deep knowledge in Aero- and Fluid- Dynamics have helped him optimize swimming and biking evaluation. His fascination for the modern but very simple invention, the bicycle, and his engineering background have made him an expert in the field.

He is a marathoner and triathlete and was a competitive swimmer in college. In 2015, shortly after his 60th birthday, he completed his first Ironman distance triathlon in Cozumel, Mexico, and plans to do several more. 

Besides focusing on the analytical and technical aspects of endurance sports training, he is also responsible for driving many of the business development aspects of the organization, including how to always improve the value provided to Racelab’s team members…


Dave joined Racelab as one of the nation's top adventure racers. He is a CAT1/Pro level Mountain Biker whose resume includes an impressive number of podium finishes in events ranging from just over two hours to just under two days. He was featured exclusively in the Outdoor Life Network's televised coverage of the Balance Bar Adventure Sprints Series and has worn the CalEco yellow leader's jersey as a member of the Epinephrine adventure racing team. When not racing, Dave works as a personal fitness trainer, adventure racing coach, mountain bike coach and freelance writer. In 1995, he spent five months running and biking through Eastern Africa.


In addition to more than 900 hours of personal, on-the-course race experience, Dave has spent years coaching both elite and amateur athletes to the podium. He is a fantastic coach who brings out the very best in his athletes.


Dave has been a Racelab Coach for over 14 years and we are very lucky to have him. He is known for his epically brutal, yet very effective and fun workouts.

2015 Dave.png
Edited Image 2014-4-10-14:42:22

Josh terwoord

Josh Terwoord is the Head Coach for Racelab Fort Collins. Josh grew up in Ohio and started distance running at the age of 13. After high school, he enlisted in the Air Force and was stationed near Phoenix where he started training with Racelab in 2004.


Josh has been a Professional Triathlete who focuses on long distance events. Since he started training with Bettina, Josh has run many marathons, including a personal best of 2:36 at the Boston Marathon. He started racing triathlons in 2007 and has qualified for USAT Age Group Nationals multiple times, raced two 70.3 World Championships and two Ironman World Championships in Kona (9:45 in 2012 and 9:15 in 2013). His personal best Ironman triathlon of 9 hours, 4 minutes includes the IMAZ amateur run course record of 2:52. 

Josh attained a Bachelor's Degree in Exercise Science in 2011 and became a USAT Certified Coach in 2012. He works closely with Racelab's Head Coach, Bettina Warnholtz, to achieve his goals and has represented Racelab's mission extraordinarily well throughout the years.


Josh also coached Northern Arizona University’s triathlon team to two National Championship qualifications, taught a triathlon class at NAU, coached swimming for a junior triathlon team, and currently coaches athletes individually in Fort Collins, Colorado

Johann Warnholtz

Johann has been running since he was 8 years old and started competing in triathlons at age 15. He is an Ironman finisher, a passionate ultra-marathoner, and in May of 2015, he completed a self-imposed challenge of running 30 miles per day for 7 straight days. He is constantly looking for ways to further challenge himself and exceed his limits.

Over the past 10 years, Johann has gained extensive experience and knowledge by working under his mother, Bettina, and has helped many athletes improve and succeed. He has become a successful and effective coach by using knowledge gained from earning a BS Degree in Exercise & Wellness at Arizona State University, Bettina's guidance and mentorship, and his USA Triathlon Coach Certification.​

Johann has taken particular focus in growing his expertise in running mechanics, swimming technique, weight loss, strength and conditioning, and general fitness outside of endurance sports. He runs a personal lifestyle blog, called Run, Wander, Wonder that covers a range of subjects from day to day training, to training while traveling, adventure travel, and general fitness.  ​


stephanie Warnholtz woods

​Stephanie began running in high school and was affectionately called Miss Congeniality, as well as "Best Motivator" on her high school cross country team. In 2004 she took up triathlon and began working as Racelab's administrator. During that time she was the Youth Coach for Racelab's running program for children as well as the Race Director for the Run 4 Fun Kids Running Series. 

Stephanie has completed many races including 2 Ironman triathlons, many 1/2 Ironman races, countless Olympic and Sprint triathlons, several Marathons and an Ultra Marathon. After taking a few years to work as a Youth Counselor on the Disney Cruise Line and to cycle across Africa with her husband in 2012/13 (3500 Miles and 9 Countries in 6 months), and becoming a Mom to a beautiful little boy, she is working her way back to training.

In addition to administrator, Steph has many other titles including, but not limited to: Event Planner, Travel Agent, Order Coordinator, and more. She very much enjoys interacting and working with people (all sorts!) and loves to plan events that make Racelab the best and most fun team around!

bottom of page