At D21, we will help you establish a sustainable synergy of effective training and proper nutrition to bring you to your BEST and keep making it better!
As a professional expert fitness studio, we allow both current and prospective clients the opportunity to invest in their long-term health and perfect their bodies through our comprehensive service, which includes personal training sessions, nutritional advice, and targeted treatments.
Here at D21, we find success through our simple philosophy and methodical approach. We implement a “good, better, best” system that allows our members to enjoy their lives — while remaining healthy and fit.
We are more than just a gym: we are a fluid studio that will refine our services to fit your specific needs. When you walk through our doors we fully commit to you and your success, no matter how difficult the task at hand. Our team is ready and waiting to help you find long-term fitness – are you?
“If it doesn’t CHALLENGE you, it doesn’t CHANGE you!” – Unknown
To spread awareness of the importance of a comprehensive, sustainable, fit, and nutritious healthy lifestyle.
To deliver optimal results based on individual priorities that make a lasting difference in our clients’ lives, and to promote active involvement within the community.
To educate and engage men and women with varying needs, ages, and diverse backgrounds to expand their physical fitness capacity, and to be extraordinary in their own way.
To reach and inspire 365+ new clients in 2018, and to be recognized as the premier fitness environment in our community.
D21 Fit Studio is committed to offering various high-quality programs with customized training to promote fitness and a sustainable healthy lifestyle.
- Utmost integrity
- Continuous innovation, development, and improvement
- Open communication
- Active community involvement
- Mission-driven
- Emphasis on health and happiness
- Teamwork and collaboration
No matter what your training goal – weight loss or gain, increased body and core strength, and/or improved alignment and flexibility – our comprehensive approach will help you achieve and sustain your healthy lifestyle goals.

Dietrich Horsey has dedicated more than 20 years to helping others feel, be and live healthfully. As a health expert and fitness trainer, he works with successful and professional clients who want to achieve their fitness goals.
Dietrich specializes in corrective exercise, with a background in bio-nutrition. Converging programs that focus on correct body mechanics and healthy diets are the basis for his success and the successes of his clients.
Dietrich has developed and implemented customized fitness programs and nutritional plans for countless individuals of various ages, genders, ethnicities, and ability levels. He uses his broad knowledge of fitness, health and nutritional topics to teach, train and consult his clients toward living a healthier lifestyle. He provides uncompromising professional excellence so that his clients will learn to honor their health, nurture their bodies and live their most extraordinary lives. D21, Dietrich’s health and fitness training and consulting firm, takes a holistic approach and focuses on the powerful link between training and nutrition

Dietrich Horsey has dedicated more than 20 years to helping others live healthfully. Dietrich specializes in corrective exercise, with a background in bio-nutrition. Dietrich has developed and implemented customized fitness programs and nutritional plans for countless individuals of various ages, ethnicities, and ability levels. He uses his broad knowledge of fitness, health, and nutritional topics to teach, train and consult his clients toward living a healthier lifestyle. He provides uncompromising professional excellence so that his clients will learn to honor their health, nurture their bodies, and live their most extraordinary lives.
Dietrich’s Tip
“Everyone likes to work on their favorite body part but it is important to develop all body parts to create a well balanced strong, powerful, and functional machine.”

Haley graduated from Grand Valley State University in 2015 with a Bachelor of Science in Exercise Science. While in college, Haley participated in dancing and intramural volleyball. She also did fieldwork in the CrossFit scene as well as Sports Performance. After graduation, Haley moved to Central Wisconsin, where she worked as a personal trainer at Anytime Fitness. There she worked with clients ranging from 20 to 65 years of age. She has experience with private training, semi-private training, as well as group classes, with a certification in personal training and CPR. Haley has recently relocated to Evanston, IL, where she has found her place at D21. She looks forward to what the future holds and hopes to change the life of many along the way.
Haley’s Tip
“Embrace the journey and celebrate the small victories! After all, it is small changes that add up to big results.”

Andreea is originally from Romania but has lived in Chicago since the age of five. She graduated from Loyola University of Chicago in 2017 with a Bachelor of Science in Exercise Science. She has had a lifelong involvement with sports, including competitive soccer, lacrosse, and basketball. Andreea was a personal trainer and a group fitness instructor in Panama City, Panama in 2016. Andreea has experience coaching clients from 10-90 years old. Andreea also holds CPR certification. Andreea currently teaches semi-private group fitness classes at D21 focused on strength, functional, and cardio exercises. She is excited to continue to grow and help clients achieve their goals here at D21.
Andreea’s Tip
“Always breathe, especially through the most difficult part of the exercise. You do not want to cut off blood and oxygen flow to your muscles. During strenuous exercise, take deep breaths and push through it. During stretches, also take deep breaths and relax!”
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