Our Team

Owner of Endurance PTC, Tim brings 20+ years of coaching experience in endurance training, performance testing, and eCycling. A former pro triathlete with a Master’s in Exercise Science, Tim blends science, sport, and strategy to help athletes of all levels optimize their potential.

Leo brings a background in road cycling, endurance mountain biking and ultra-running to his current work as an endurance trail running coach. His approach to coaching is personal and adaptable. In joining Endurance PTC, he looks forward to bringing the latest in sports science to aid his athletes in achieving their goals. 

A biomechanics expert and elite-level cyclist, Jaffa offers deep insight into cycling technique and triathlon performance. Based in the Bay Area since 2002, he brings a competitive edge and global perspective to performance coaching.

Our lab tech assistant, Jacob, blends his experience as a collegiate triathlete, marathoner, and ultra-trail runner with foundational knowledge in Kinesiology. Having recently graduated from University of Wisconsin-Madison with a degree in Exercise and Movement Science, Jacob is excited to join the Endurance team this year!

You'll see him around the lab, leading eCycling classes, and at our Thursday morning group runs!

A seasoned Ironman triathlete and marathoner, Caroline specializes in long-distance training for runners and triathletes. Her coaching is perfect for athletes balancing competition and life - including parenthood.

With a Master’s in Exercise Physiology and 25+ years of personal training, Beth leads our injury-prevention efforts and co-develops our eCycling program. She's passionate about biomechanics, community coaching, and functional fitness.

Hope blends decades of road cycling experience with 20+ years in sports medicine. Her classes emphasize form, safety, and long-term strength—perfect for anyone recovering from injury or new to endurance sport.

Andrew is a trusted resource for cyclists across Marin County. Whether you're dialing in bike fit or fine-tuning your form, his personalized approach blends technical expertise with hands-on support.

Director of treat management, professional urban sled dog, habitual tail wagger, and official greeter.

With over 25 years as a health and fitness specialist in Marin County, Charles is known for his warm, intuitive approach. Each session begins with, “How do you feel today?”—allowing him to tailor workouts on the spot. Charles blends cardio, strength, and flexibility training to create effective, personalized routines.

Certifications:

ACSM Advanced Personal Training

Exercise for Older Adults

Spinning & TRX Instructor

Christine is a licensed orthopedic physical therapist turned personal trainer with a passion for functional strength training and injury prevention. Her thoughtful programs are ideal for those navigating physical limitations while working toward sustainable strength and mobility.

Specialties:

Post-rehab strength

Trail running

Functional movement for long-term wellness

A former collegiate and pro soccer player, Kelli is a powerhouse of experience and curiosity. She has completed 25+ continuing education programs and holds certifications in everything from youth fitness to sports psychology. Her energetic, holistic coaching style blends fun with functional science.

Certifications:

BS Exercise Science (Biomechanics)

BA Sports Psychology

National Strength Coach Certification

Certified Youth Fitness Specialist

Certified Speed & Agility Coach

Mark’s experience spans military training, competitive athletics, and two decades of fitness coaching in Mill Valley. A veteran of the South African Defense Forces and ISSA-certified trainer, he helps clients of all ages achieve lasting transformation—whether they’re elite athletes or new to fitness.

Philosophy:
“Health is not about the weight you lose but about the life you gain.”