Welcome to Stay Fit With Sue

Sue Kartheiser Fitness and Nutrition is a private, boutique fitness studio in Fort Collins, Colorado. The environment here is supportive, encouraging, uplifting, safe, and clean. Clients can choose to work in private, semi-private or group sessions.

The fitness facility offers a variety of functional training equipment used to increase strength, balance, cardiovascular capacity, and flexibility. Depending on needs and goals, nutrition sessions take place in a variety of places including client kitchens and pantries and grocery stores. All fitness and nutrition sessions are customized for each client. The goal is to teach clients to adopt a healthy lifestyle by incorporating fitness and nutrition into their daily lives.

Some of the obstacles many people face in trying to live a healthy life include:

Knowing what to eat and what not to eat for optimal health
Finding time to exercise
Finding time to shop for food and prepare meals
Setting realistic fitness and nutrition goals and reaching these goals
Making excuses instead of working to get results
Feeling overwhelmed and not knowing how to get started

Sue Kartheiser Fitness and Nutrition is a place to overcome these obstacles. It is a place that teaches you step by step, how to get fit and stay fit in a way that works for YOU. By visiting this website, you have taken a big step toward living a healthy and fit life. Take the next step by clicking here to contact Sue about starting your program!

*Sessions are by appointment, fees are per session, there are no membership dues.

Our Studio

Meet Sue Kartheiser

I built my business, Sue Kartheiser Fitness and Nutrition, out of my passion for helping people change their lives by teaching them to Get Fit, Be Strong and Live Well. I believe that fitness, health and wellness are a way of life. Each of us has the ability to get fit, to live well and to be strong. Each of us has the ability to believe in ourselves and choose to get results over making excuses. Because each individual is different, our personal wellness plans and daily routines will be unique to each of us. As our lives evolve, our wellness plans and routines must evolve as well. I understand that you have your unique set of goals and needs; we can work together to achieve success.

My role as a Personal Trainer and Nutrition Counselor is to work with each client to:

Understand and identify the components of his/her current lifestyle
Identify reasonable, challenging yet achievable and sustainable long and short term health, fitness and wellness goals
Design customized fitness and or nutrition plans targeted to achieve wellness goals
Track progress and adjust accordingly
Establish accountability for doing the work necessary to reach goals and set new ones

My background includes:

Vanderbilt University: BS Special Education Visual Impairments, BS Elementary Education
Fitness certifications including: TRX, BOSU, Aerobics, Aqua Aerobics, Personal Training, Kickbox, SPIN
Trinity School of Natural Health: Certified Nutrition Counselor
Classroom Teacher of the Blind and Visually Impaired
Technology Sales Management for Microsoft, Intel and TeleSensory
Personal Trainer, Fitness and Nutrition Consultant, Business Owner since 2003

“You can have results or excuses, not both. You Choose”

Sue Kartheiser

Contact Me

What Sue’s Clients are Saying

Always a thoughtful and innovative workout based on what I want to achieve. For over 8 years I have loved and appreciated all my time in the gym with Sue. ❤️Melissa
Melissa R.
Customized one on one sessions that allow you to reach achievable goals. A workout designed for "your" body to help you reach your own personal fitness goals! (I.e. my six pound weight loss!!) The feeling of a health club without the "audience" of a health club. One on one motivation! Helps make me accountable to someone I know who cares about helping me reach my personal goals.
Cathy W.
I prefer your gym because I get the personal attention that I really need to make my workout count. I can really focus on what I need to get done. You give me a plan and stay on top of me. This is particularly helpful when I am feeling less than motivated. No one is going to give me that motivation in the health club like you can in your own personal gym. No one is going to notice in the gym if I decide to get off the treadmill after only 20 minutes and go home. You are there to show me the correct way to use the equipment and the best way to use the equipment to get the best workout. I don't think you get this very easily from the Health club. And, by working out with you, I am assured that I am working out at a pace that works best for me, my body, and my health goals. Doing a class in a health club might be fun, but all too often the instructors do things that better suit people with perhaps better abilities than me. Training with you is just as fun if not more fun than a big class and I don't walk away with an injury or a pain simply because I wasn't being taught at the right level for me.
Karen A.
Enjoy the privacy and 1:1 attention. Motivates me to do exercises I would not do on my own. Compassionate style. Training tailored to the individual with respectful consideration of each persons differences. And it is more than just training, always willing to share experience and knowledge.
Kristina P.
I love that you are very conscience of form so that the person you are training doesn't get injured. I love that you try different exercises based on ability and improvement. I love that it is quiet and peaceful. I don't like neon and loud music and I don't like being "judged" by others who may be doing things more wrong than me. I love that most of the things we do, I can do at home. I'm looking to get in shape now that I'm over 40 and I would love to loose about 10 pounds.
Kara B.
Private Attention to Clients Needs. Personalized plans for clients goals. Clean, Safe, comfortable, welcoming environment. Measurable Results.
Dr. Jordan L.
"The single most important thing that has affected the quality of my life, along with a healthy diet and lifestyle, is working out. I have been working out with Sue for somewhere north of 15 years, and I am 60 years old. While I am pleased that I get voted for best body in my tennis team even though I am the second oldest by decades, I am even more pleased that I have the strength and endurance of a much younger person. Working out is a discipline that is of primary importance in my life. Thank you, Sue!"
MaryAnne S.
I enjoy being pushed to my limits during Sue's workouts!
Connie H.
I’ve been working out with Sue for several years and cannot imagine working with a different trainer. Despite having a multitude of clients, Sue has taken the time to get to know my body and my style, and can easily modify my workout on-the-spot to accommodate an injury or a low energy level. She doesn’t let me off the hook; just makes a modification so that I can continue to work out and feel accomplished. As I’ve aged, and I’m 60 now, I’ve come to realize that I have to honor what may be going on with my body and change my workout to (again) accommodate my body’s needs. And as Sue and I have worked together over the years she has seen my body change and I rely on her ability to offer a wide variety of exercises that can get the results I want without injuring a knee or shoulder in the process. Best of all, I appreciate Sue’s flexibility in allowing me to come to stretch class with my grandson and daughter-in-law. We’ve had lots of fun and love keeping it all in the family.
Sue O.
The benefits of training with you in your private gym is that "one-on-one" attention. You, the trainer, pays attention to form, pace, heart rate, and every detail that makes every work-out complete. Being in a private gym is more personable. It is not only a physical work out, it is equally a mental work out that clears the brain and provides a positive energy you feel all day. With a trainer there is less chance of injury, because there is complete focus on every move that you make during a work out. In a private gym you can workout, talk about proper dieting and the benefits of nutrition.
Carla M.
You make me believe I can do things that I never thought I could do.
Justine G.
"Personal Attention" "Flexibility" "Positive Body Image"
Deborah W.