Koi Fitness’ professional instructors possess extensive experience instructing outdoor group exercise training. They each have unique competitive athletic backgrounds; many have coached amateur and professional athletes and have attained the highest level of education and certifications, including physical therapy experience and nutritional expertise.

Stevan Krstic

Stevan Krstic
Stevan has over 10 years of experience in the fitness and exercise industry. He has achieved the highest level of health, fitness and performance certifications, including Strength and Conditioning Specialist certification through the National Strength and Conditioning Association, the American College of Sports Medicine’s Health Fitness Specialist certification and the Club Coach certification from USA Weightlifting. Stevan was awarded a Bachelors of Science in Kinesiology and Exercise Science/Physiology from San Francisco State University. The “Original Boot Camp Guy” in San Francisco, Stevan co-founded one of the first boot camp style fitness programs in San Francisco in 1999. Stevan has excelled at several sports, including football, soccer, martial arts and Olympic style weightlifting. He achieved national success in track and field and was honored as a Collegiate All-American, and competed in several bodybuilding events in Central California. He has coached several athletes to collegiate nationals while coaching at San Francisco State University (2001-2003). He’s also developed competitive high school athletes for the collegiate careers in crew and soccer. Contact: stevan@koifitness.com

Amie Ahlers

Amie Ahlers
Amie graduated with a Bachelor of Science degree in Kinesiology from San Diego State, and has been working in the exercise, nutrition, and wellness field for over nine years. She is certified as a personal trainer through NSCA, holds a certificate in acupressure, and has been a nutritional consultant for the past nine years. She currently works with people one-on-one with a diet and exercise program for weight loss, maintance, and finding the right balance, as well as a personal trainer in San Francisco. She has played soccer and basketball throughout her life, and currently enjoys long distance running, swimming and kayaking. Amie joins the team as a nutrition counselor. Working with others to make good nutrition and exercise part of their lives is Amie's passion. If you have the desire to change your eating habits, Amie will show you not only how to diet to lose weight but how to maintain it for life. She has helped both men and woman lose 5 to 100 pounds. Contact: amie@koifitness.com

Vaj Granelli
  Vaj Granelli
Vaj brings a lifetime of physical fitness and fighting training to Koi Fitness. He has spent time on both sides of the rope with a top-notch competitive record for himself and the athletes he's trained in boxing, kickboxing, muay thai, combat karate, aikido, ju jitsu and hand-to-hand combat. A third-generation San Francisco boxer, he has been in the ring for 21 years and kickboxed for 14 years. Vaj has trained many golden glove champions in San Francisco as well as California U.S.A boxing champions. Over the years he has worked with many world champions in the boxing and kickboxing world. Vaj also holds the rank of Shodan in Aikido.
Contact: vaj@koifitness.com
Alyssa Hershkowitz
Call her a "lifer." Why? Alyssa has been active all her life trying just about every sport- gymnastics, diving, soccer, softball and basketball then high school swimming, volleyball and track. Apparently she couldn't make up her mind what she liked the best. In college, she picked up distance running to keep herself in shape as she earned her Bachelors degree in Exercise and Sport Science from the University of Utah in Salt Lake City. In 1996, Alyssa began her career as a wellness coordinator for a large corporation managing a small fitness facility implementing health prevention and promotion programs for its employees. Alyssa moved to San Francisco where she continued her career in wellness as the Health and Fitness Director for the Embarcadero YMCA managing the health and fitness department for over 8 years where she has taught a variety of exercise classes including boot-camp, step, resistance training, indoor cycling, and cardio kickboxing. Alyssa has competed in numerous distances ranging from sprint to the full Ironman triathlon. Her commitment is to help people find the fun in movement, to live a functionally robust life, and to realize the benefits of setting goals because "you never know what you can accomplish unless you try." Alyssa holds certifications from the American College of Sport Medicine as a Health Instructor, American Council on Exercise, American Heart Association CPR and First Aid, and YMCA Group Cycling Instructor. Contact: alyssa@koifitness.com

Claire McGowan

Claire has been an athlete all of her life, first as a soccer and tennis player until college and then making the leap to distance running. Eleven marathons and three ultra marathons later Claire moved her focus onto triathlon. Claire has been racing at the Elite level for the last three years and has represented the USA at three triathlon World Championship events, completed four Ironman and countless shorter races. After a three year stint in marketing, Claire left corporate America to race and coach full time.  As the founder and head coach of Diesel Coaching, Claire helps people of all ages and abilities to train for and race running and triathlon races of all distances. As an experienced Spinning instructor, personal trainer, postural alignment specialist and running and triathlon coach; Claire looks forward to combining all aspects of her experience while enjoying the great outdoors with Koi Fitness. Besides certifications in Spinning, and Egoscue Postural Therapist, Claire has a bachelor’s degree in Kinesiology and Psychology from Wake Forest University. Contact: claire@koifitness.com

Galen Pewtherer
Galen has been a professional trainer for 3 years, and a competitive athlete for 20. He started out as a cyclist and raced in the United States and Europe for several years. From there he moved on to marathons, and then to ultras, and in 2006 started Adventure Racing. He has worked with athletes of all levels, and specializes in getting new athletes to produce results beyond their expectations. His motivation as a trainer -- that athleticism should be an important and valuable part of everyone's life -- drives him to find ways to make that possible for anyone, and he is willing to go to great lengths to make that happen. He excels in endurance and ultra-endurance events, and strives to impart the lessons of perseverance, mental toughness, and dedication that make him a successful athlete to the people he trains. Contact: galen@koifitness.com

Sean Dries
Sean has been working in the fitness field since receiving his certification from the American College of Sports Medicine in 1996. During his childhood and teenage years, Sean was inactive, only becoming dedicated to an improved fitness level as a junior in college. When Sean moved to the Bay Area in 1994, he really kicked things up a notch and decided to make fitness a top priority. Concentrating on training and fitness has improved his self-esteem, as well as his appearance. Sean decided to make a career change and assist others in realizing the same remarkable life changes by tapping into their own inner potential. Sean served as the Fitness Director of the Embarcadero YMCA from 1998-2004.  He is a certified Health/Fitness Instructor with ACSM, Spin instructor with Madd Dogg Athletics, wellness coach with Wellcoaches, Basic Life Support Instructor with the American Heart Association, and Group Exercise instructor with the YMCA of the USA.  He is also an accomplished triathlete and marathoner, as well as the very proud father of 2 amazing little boys - yet another fantastic life changing wonder. Contact: sean@koifitness.com

Shannon Boughn
Shannon received her bachelors from the University of California, Santa Cruz and has done coursework in exercise physiology, functional anatomy, exercise psychology and nutrition. She has been a triathlon coach and personal trainer for the past eight years and currently directs a large triathlon training program through the Embarcadero, Presidio and Richmond YMCA's. Shannon has coached hundreds of athletes for races ranging from 5k runs in the Presidio through Ironman Competitions in Brazil, Canada and New Zealand. A competitive triathlete and occasional adventure racer for the last decade, Shannon has been with Stevan Krstic as his endurance specialist for the past 3 years. If you are interested in training for races let her know.she will probably talk you into something "just a little bit longer". Contact: shannon@koifitness.com

Heather Robinson
Heather Robinson is a certified personal trainer and group cycling instructor with a diverse athletic background and a spirited sense of fun.  She has a B.A. in History and Business Administration from the University of California- Riverside , where she played varsity collegiate basketball.  She is a member of the Embarcadero YMCA’s triathlon training club, rowed with the Kahakai Outrigger canoe club, and played for the California Quake, a professional women’s football team.  In addition to her certification from the National Strength and Conditioning Association, she has completed course work in nutrition, biomechanics, exercise physiology, and fundamentals of group exercise. Heather brings a creative approach to every exercise, incorporating games, playful competition, and mischief into fitness.  Her tough workouts combine strength, agility, speed, plyometrics, flexibility, cardio endurance, and amusement.  She is also a freelance writer, specializing in fitness, wellness, and the joys of the sporty life. With her powerful voice and no-nonsense attitude, Heather is guaranteed to make you work hard – but you’ll be surprised to find yourself enjoying it.
Contact: heather@koifitness.com

  Karim Derqaoui
Karim is currently completing a Masters Degree in Exercise and Sport Science from San Fransico State University where he earned his BSc. in the same field. In addition to his graduate work, Karim stays busy as a strength and conditioning coach at St. Ignatius High School here in San Francisco, a personal trainer at the San Francisco YMCA, and runs the fitness program at an annual soccer pre-season camp. He holds several certifications including ACSM Health Fitness Specialist, NSCA Strength and Conditioning Specialist, and YMCA Personal Trainer. Fluent in French, Karim has been recognized at national level for his academic excellence by being invited to join Phi Beta Kappa and has been published in the SFSU Kinesiology Journal of Student Research. His movement background includes soccer, kickboxing, Brazilian dance, and martial arts. Karim brings to Koi an experience training a wide range of athletes, recognized academic excellence in the field of exercise physiology, and a dedication to making sure everyone he trains knows they're in good hands.
Contact: karim@koifitness.com