About our team

About Us

Holly Peng MD

Family Physician and Integrative Health Coach


"I believe the foundation of "being the best version of you" and "living life to its fullest" is having HEALTH. And health is not the absence of disease but an optimal state of mental, physical and spiritual well being. I believe that everybody in this world can tap into that deserved authentic health and there is nothing more important.

Growing up with my grandmother (who lived until she was 105) I would hear her mantra in my ears -"watch over your health- without it, nothing else matters".  All the money in the world would be useless without your health. Without your health, you cannot be en effective parent, worker, or leader.

I believe furthermore that we were put on this earth to experience an exuberant life and the power to attain it is inside each one of us.

Here at Island Trek Fitness, we are dedicated to helping you achieve this exuberant life."

Dr. Peng is the founder, owner, and manager of Island Trek. She has practiced clinical medicine for the past 20 yrs for Group Health and Kaiser Permanente and now is self employed as a contract/locums provider. Holly grew up in Tuscon, Arizona and received her undergraduate degree at the University of Chicago, medical degree at the University of Arizona School of Medicine. Holly completed residency in Family Medicine with University of Washington and Group Health. Dr. Peng is board certified in Family Medicine and has a Diploma in Tropical Medicine and Disease through the London School of Tropical Medicine. She is thrilled to be a Integrative health coach, a graduate of the Institute of Integrative Nutrition. Holly lives in Seattle, Washington and is the proud mother of her labradoodle Barkley.


Adam Fawcett

Certified Personal Trainer


"I want to help you deepen your awareness and control of your own amazing body-machine, and help you to inhabit it with greater effectiveness, power and grace."

Adam is the founder of Vibrant Fitness, a functional fitness training company in Langley, WA. His excitement and love for good form and effective exercise are contagious and he is known for his enthusiasm, intensity, and humor.

His unique style of functional fitness training draws on decades of practice in Tai Chi, Chi-Gong, and yoga. His earlier schooling and career experience include Mechanical Engineering and Waldorf Education, both of which have augmented his strength and movement training skills.

Adam is a CPT-NASM- certified personal trainer, National Association of Sports Medicine.

Adam has been helping people improve their lives through fitness training and group exercise for over twenty years.

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Marcie Costello LMT, RYT, CRM

Yoga Instructor Reiki Master

Licensed Massage Therapist

"I teach from my heart and I am so grateful for all the students who come and share their beautiful souls- they inspire me more than they could ever know."

Marcie Costello is the founder of Shakti Yoga and Wellness. She is passionate about the many healing benefits that yoga offers and is appreciative everyday for the privilege to share such a beautiful practice with others. She believes that through the practice of yoga, there is no limit to how much one can grow physically, emotionally and spiritually.

Marcie has been practicing yoga for over 20 years. She is RYT 500-hr Yoga Alliance Certified. Her formal training was through Yandara Yoga Institute , Teacher Trainer and Course Development at 200 and 300 hour level programs.

Marcie graduated from the Utah College of Massage Therapy in 1998 and has completed nearly 1500 certified hours in various modalities of massage. She is also a Reiki level Master/Teacher with study interests in Pranayama, Meditation, Ayurveda, Sanskrit, Mantra, and Ritual Ceremony.

Whether on the mat or on the massage table, she inspires her clients to calm the nervous system while honoring their boundaries of the mind, body, and spirit. She offers subtle adjustments with an emphasis on safety.


Certified Personal Trainer

Alex Pearl

"My passion is making fitness fun for you and bringing you to the beautiful places of the Pacific Northwest."

Alex Pearl has lived many lives in this lifetime. He has been a track star and a sluggish junk foodaholic. He has been an activist for Greenpeace and has lived out of his car. He has sold bamboo houses on the Big Island of Hawaii and has been a camera man for college sports.

Currently Alex Pearl's passion is helping people achieve peak physical condition as a certified personal trainer and track coach. After years of experimentation, Alex knows that this is a very personal journey, and he is excited to share the habits that have helped him get into amazing shape.

When Alex finally decided to make a change to get healthy, his first stop was the woods. Hikes through nature invigorated his body and cleansed his soul, and he knows they will do the same for you. Get ready to experience the raw beauty of Whidbey Island with Alex Pearl.

Lis David

Lis David is the chef owner of Magical Feast, a catering company on Whidbey Island, where she creates cuisine inspired by her travels through the Mediterranean using local ingredients. Her hobbies include, reading and writing about food, running with her dog Abby and when she can, travelling to explore cultures and cuisine.
She has been working in the restaurant & food industry for 18 years, starting her career in D.C. for acclaimed chefs José Andrés (at Oyamel, Café Alantico & Mini Bar) and Michel Richard (at Central Michel Richard). She is classically trained in Culinary Arts Management from Kendall College in Chicago, Illinois. She spent many years cooking and managing restaurants for James Beard award winning Chef Shawn McClain at both Spring and Green Zebra.  
She and her husband moved to Whidbey to their orchard to be in the heart of good food. She took a job at Orchard Kitchen, eventually becoming sous chef where she found great pleasure in cooking good food for the people of Whidbey Island. She enjoys cooking classic dishes with bold flavors, using fresh local ingredients.


George Bullis

certified personal trainer

George has dedicated his entire career to fitness. He is a certified personal trainer with ACSM and is a USA Track and Field running coach. In addition, he teaches Pilates and is certified in CPR.

He hails from New York City where he worked in law enforcement and was a police mountain bike officer. George also is a master instructor for unarmed defense.


He lives locally on Whidbey Island and stays active with running, biking, paddle board, basketball, tennis, Pickleball, and swimming.