About Us

Cassie Dimmick, MS, RD, CSSD is an owner of Achieving Your Best, a nutrition and training facility in Springfield, MO where she works with an exceptional team of dietitians, personal trainers, managers, and administrative professionals.

With 20 years of experience under her belt and several professional certifications, including Registered Dietitian Nutritionist, Board Certification in Sports Dietetics, American College of Sports Medicine Certified Exercise Physiologist, and Road Runners Club of America Certified Running Coach, Cassie specializes in helping clients perform at their best and reach their goals in a realistic, enjoyable way.

In her free time, she loves to run, cook, lift weights, travel, and spend time with her wonderful husband, two teenage daughters, two dogs, and awesome friends.

Matt Jones is co-owner of AYB and is in charge of operations of the facility. He carries two degrees from Drury University in Psychology and Criminal Justice. He is certified as a Personal Trainer through the American College of Sports Medicine (ACSM), and working toward his NSCA Strength and Conditioning certification for 2020. Matt has been a group and personal trainer for 7+ years, and has been with Achieving Your Best since February of 2017.

Matt loves to contribute to the health and wellness of people from the great Springfield, MO area. His goals at AYB are to continuously grow as a leader, and see AYB fulfill its philanthropic endeavors. Matt is committed to AYB and its excellence, and to all the people that make this community special.

Matt is engaged to be married in 2020 and his dog Ellie Marie is usually hanging out at the gym loving everybody.

I grew up being active, doing everything from chores on the farm and horseback riding to soccer, volleyball, and Ultimate Frisbee. All of those facets helped to establish a solid work ethic and the love for activity and health from a young age, which only continues to grow today.

I love to explore all varieties of movement and fitness, and over the years it's been anything from triathlons to obstacle races to power lifting, and currently CrossFit.

I've come to absolutely love heavy lifting and utilize it as the foundation of my own fitness, but there's also nothing I love more than a good, hard conditioning session to kick my butt in gear. I thrive off of physical challenges, conquering myself mentally and learning to control and own my mind and body a little more every day.

Fitness and wellness is my passion. my lifestyle, and my privilege, and an outlet for my drive and competitive nature. But more importantly, it's the gift I'm blessed to be able to pass along to everyone I have the joy of training.

I love life and I love helping people enjoy it! I grew up in the beautiful state of Hawaii, where I learned so much about how different cultures appreciate and enjoy life. I take great joy in bringing people together and creating awesome life experiences.

In 2003, I came to Missouri to attend Evangel University, where I learned many lessons on and off the football field. After graduating, I spent the next 8 years training athletes to be the best they can be. I also spent many hours helping hard-working everyday citizens reach fitness goals that they never knew where possible for them.

I have so much passion for helping people on their journey to a healthier life! Nothing is easy, but together I know we can make it happen. I am very excited to be a part of the great staff at AYB, where it will be an amazing community!

Jill Trotman is a registered dietitian with 20 years of experience helping adults, children, teens and families improve their health through nutrition. Along with her Masters in Public Health, she is a registered and licensed dietitian and a certified diabetes educator (CDE). Her specialties include diabetes, chronic disease prevention, and plant based nutrition, and her favorite part of being a dietitian is working individually with clients to develop a personalized realistic plan.

In her free time, she grows vegetables in her garden, runs with her black lab, swims, and enjoys time outside with her family. She loves cooking for her hungry husband and two daughters. One of her goals is to make the world’s best muffin. If you are lucky, you may get a sample at AYB when she tries a new recipe!

Alix Opfer is a Registered Dietitian Nutritionist and Certified Personal Trainer with a Master’s degree in sports nutrition. From Springfield, Alix stayed in her hometown and joined the AYB team in 2018. She completed her Bachelor’s degree at Missouri State University in Dietetics and her Dietetic Internship and Master’s degree at St. Louis University. She also competed in soccer for 4 years at the Division 1 level for Missouri State University where she was a center midfielder. Alix enjoys helping different populations reach their goals through nutrition and exercise in a sustainable way.

With a client centered approach, she feels it is important to get to know each of her clients and help them to determine how they can be successful. In her free time, she loves to hang out with her fiancé and dogs (Glen and Gary), run/lift, go down to Table Rock Lake, try different restaurants and watch the Chicago Bears and St. Louis Blues!