1293 Main St #2

Windsor, CO 80550

(970) 686-2582

24/7 Customer Support

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Personal Trainers

Trainers

Brad Bertoch

Owner / Trainer

Fitness has always been a passion of mine, but I found myself overweight and unhealthy in my early 20’s. I made the decision to better myself and my life by learning as much as I could about nutrition and exercise. I lost over 40lbs and added lean muscle during my fitness journey. I have not stopped since and became certified as a trainer in 2014 and also was certified as a fitness nutrition specialist. I’ve competed in bodybuilding and coached many on the road to their bodybuilding competitions. I’ve owned the gym since 2018 and have loved every minute of it! We are here to help anyone that wants to better themselves by getting stronger, leaner, and more mentally focused! Consistency is the key to success and couldn’t be more important to change your mindset and ultimately your body composition!

Natalie Smith

Owner / Trainer

Helping others succeed is one of my greatest achievements. While working towards reaching my own fitness goals I found that helping others reach theirs was much more fulfilling. I love watching people transform into the best possible version of themselves.

My focus is on exercise, nutrition, lifestyle and most importantly balance between them all!! Wether it be fat loss, muscle building, strength training or just wanting to be a healthier you, myself and the team at ONYX Athletics would love to be part of your journey!!

Rachel Hernandez

Personal Trainer

Starting my personal training journey was an easy decision. After having hired a trainer myself when I was in serious need of motivation and accountability, it was life changing. After the birth of my daughter, I was very overweight, had no energy and my self confidence was completely gone. I knew I needed to change. After training for over 2 years with my former trainer, it made me realize what kind of career path I wanted to take. I now have a passion for fitness and want clients to see how rewarding it is to feel great, have energy and possibly be an inspiration to others.

I became certified in personal training through NASM in May of 2021. I have trained clients of all ages and my experience is gaining momentum. I may be new to the health and fitness industry, but I love what I do and hope my future clients will see the passion I have for this profession with each session they push themselves through.

DeAnna McDaniel

Personal Trainer

I have been teaching at Onyx for a little over a year. I became NASM certified in January of 2022 and TRX level 1 certified in August of 2022. I have a passion for helping people achieve their fitness and wellness goals and love working with all ages of clients. I currently teach the Silver Sneaker circuit and stretching classes along with the Cardio/strength class and have a handful of clients. Currently, I am working on my nutrition certification because I really love to help people understand that food and movement are medicine!!

Gautum Srinivasan

Personal Trainer

I believe movement and strength are foundational keys to building an independent and fulfilling life. Movement starts in the brain and allows us to interact with the surrounding world. Strength training and movement training are the avenues through which we train the nervous system to allow us to live life to the fullest. Training can accomplish everything from rehab to injury prevention to building stronger relationships and even allowing us to make core memories with our loved ones. Fitness is as crucial to a healthy life as nutritional food, staying hydrated and sleep. I believe fitness is for everyone and I’m thrilled to be able to share my passion with those around me!

I’m specialized in biomechanics, neuroscience, rehab and athletic performance.

Years of Experience:
14 Years
Credentials:
BS, Human Biology – University of Southern California
MS, Kinesiology & Neuroscience – The Pennsylvania State University
NASM Certified Personal Trainer

Spencer

Personal Trainer

I’m a coach, former bodybuilder, father, and husband to a driven, amazing woman. With over a decade of experience in bodybuilding and 12 shows under my belt, I’ve learned that real strength goes far beyond the gym — it’s forged through discipline, consistency, and mindset. My mission is to help others become the strongest, most resilient versions of themselves — physically and mentally. I coach people through training, nutrition, and lifestyle habits that create lasting transformation. I don’t believe in quick fixes or excuses — I believe in showing up daily, even when it’s hard. I’ve lived this life, I’ve walked the path, and now I help others do the same. If you’re ready to change, I’m here to lead. This is about more than fitness — it’s about forging a new standard for your life.

Andrea Deepe

Personal Trainer

I am a Colorado native who loves all things outdoors and enjoys taking advantage of all this great state has to offer. I earned my degree in exercise science from UNC in 2008 and I have been training people from ages 14–80, across all fitness levels, ever since! I especially enjoy working with beginners, helping them learn proper movement patterns from the start. I emphasize the value of building a healthy relationship with exercise so that it becomes part of one’s lifestyle, not a fad or quick fix. I’m here to push you, hold you accountable, and keep your workouts varied so boredom never sets in!

Nurtionist

Julie Lamasters

Nutritionist

I am a mom, wife, bikini competitor, and certified nutrition coach. I truly love helping people take steps towards a healthier, balanced life with personalized wellness nutrition plans. With my background in healthcare and as a competitor, my focus is transformative body recomposition.  With delicious, simple food in mind I design custom nutrition plans that help transform your body and your plate. I will work with you and or your trainer to design a plan that fits your lifestyle and your goals.