“I hired On Your Mark Nutrition to handle the heavy lifting regarding nutrition of two major sports performance projects and was more than pleased. After those two projects I made it a priority to work with Katie Mark on anything that requires applied and cutting edge nutrition science to find a winning edge. Work with her, as the results speak for themselves.”

“I’ve had the pleasure of corresponding with Katie regarding many aspects of Sports Performance Nutrition. Katie is a forward thinker, extremely knowledgeable, and a rising star in the world of Nutrition. Katie has the ability to incorporate science-driven methodologies into actionable practices for athletes, resulting in many tremendous individual success stories. Having worked with several RDs in the past, I can say that Katie is among the best and brightest in the business. No matter your goals, Katie is an outstanding resource who can help you elevate your results.”

“Katie Mark does an outstanding job in embracing the most recent published science and marrying it with real-world athletic application. She represents the new generation of dietitians that are also Certified Sports Nutritionist from the International Society of Sports Nutrition (CISSN).”

“As a professional ballet dancer, Katie has changed my whole outlook on nutrition. She gave me the tools to keep energized and full throughout long rehearsal days while helping maintain a long and lean aesthetic. Her enthusiasm for what she does comes through in her methods and approach, which as a client made me focused and motivated. I really enjoyed how she tailored and made my plan to work with my schedule and needs, and made everything seem so easy and assessable. The things Katie has taught me have helped changed my career and life for the best.”

“If you’re looking for someone who knows sports-specific and athlete individualized nutrition...I know no one better!”

“I met Katie because of my interest in decreasing my body fat percentage and becoming exceptionally lean again. Stress from life, work, relationships and moving to Miami from the Northern states after years of dental school got the best of me. Despite training in the gym every day of the week, I gained 30 pounds and was desperate to lose it - trying every fad to get back to “me.” I was hoping for a scientifically-driven quick fix. Little did I know, as the cliche goes: “the weight I had to lose was in my head.” Katie changed my life through her knowledge, compassion and “give a damn” approach. I read the books she suggested. I changed my lifestyle. I listened, took notes and did the things she advised. She was thorough and I followed through. It wasn’t easy. It got worse before it got better. My test results went from off the charts-bad to off the charts-good at my final follow up. I’m now healthier than ever with a positive mindset and sustainable approach to LIFE that I am forever grateful for. Her work is one-of-a-kind and applicable to every person from a once fluffy Dentist like me who loves health and fitness to your elite, Olympic athlete.”

“Katie is not your traditional sports nutritionist. At a high level in sports, the generic sports nutrition is not enough. My collegiate team had an RD available for me, but I worked with Katie because I wanted guidance that was many steps above the basics. I wanted more than the average collegiate sports nutrition service. You can 100% count on Katie to follow through and go above and beyond for you.”

“I had the pleasure of working with Katie in doing the Metabolic Efficiency test. Katie is professional, knowledgeable, and personable. Most importantly, she is able to articulate your results in a way that is both understandable and immediately actionable into your everyday life. We used the data from the test to pinpoint areas I could improve upon with my nutrition consumption and timing. Her recommendations have resulted in noticeable advances in my training and overall well-being! As a personal trainer and athlete, I would highly recommend Katie to any of my clients and fellow athletes looking to dial in their nutrition and change their life!”

“I teamed up with Katie for a three month program to not only enhance my athletic performance but to also cultivate an understanding of my body. For months, I was getting colds every other week, intestinal spasms and daily fatigue. Katie was able to get down to the bottom of my symptoms to figure out what was going on and provide a solution. This is something no other doctor, coach or psychologist was able to figure out. I was in adrenal fatigue. She worked quickly and efficiently to get me back on track toward my goals, which started with a treatment plan consisting of nutrition, meditation, yoga, and, yes, gaining the confidence to say “No”. If it weren’t for her, I probably wouldn’t be training - let alone competing. Katie Mark is more than a sports nutritionist and a registered dietitian, she is an athlete and professional who truly cares.”

“My wife and I have worked with Katie over the last year. I generally don’t write testimonials, but Katie was so fantastic that I felt I owed it to her. There’s obviously a lot of people out there who know a lot about nutrition. However, if you decide to work with Katie, I don’t think you will find anyone out there who is more passionate and cares as much as she does about her clients. What was also great for us is that we actually live in Phoenix, Arizona. So don’t worry if you don’t live in South Florida. She can still work with you to achieve your goals and get you the results you are looking for. Keep up the great work, Katie!”