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Jeff Rothschild is a Registered Dietitian (RD) with a Master’s degree in Nutritional Science and a Board-Certified Specialist in Sports Dietetics (CSSD). His clients include multiple Olympians, State Champions, triathletes competing at World Championships, collegiate All-Americans, and professional tennis players. He also works with people trying to complete their first cycling century, improve their energy levels, and learn how they should be eating to achieve their health and performance goals. Jeff is currently doing his PhD, researching the effects of pre-exercise nutrition strategies on the adaptations to endurance training.



Stef Callens is a Certified Personal Trainer and owner of Vitality Training Studio - a semi-private personal training studio in Littleton, CO. An engineer by education and after 10 years in the corporate world, Stef realized her passion is exercise, educating people on how to move better and helping them accomplish their fitness goal, regardless of what it is. She opened Vitality in 2019 to be able to provide more clients with an environment where they can feel comfortable getting stronger. Stef and the Vitality Coaches have experience training athletes and deconditioned people alike, aged pre-teen all the way up to people in their

Coaching Partners: News and Tips




With a passion for pedaling and a love of endurance cycling and stage races Nadine Stein is a bike fitter who understands how important it is to be both efficient and comfortable on the bike.  
An import from Southern Africa, and the offspring of a lifelong cyclist, Nadine grew up with cycling in her blood.  Certified through Trek Precision Fit Systems in the US and with loads of fit experience under her belt, she is focused on continuous learning and improvement. The addition of BikeFit and foot and pedal interface in January of 2020 will expand her knowledge base even further.

Coaching Partners: News and Tips
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