SplitFit now available at
Fierce by Choice

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About Fierce by Choice

Hi! My name is Derith Cass, aka Coach D., and I’m a lover of life, fitness, and the human connection. As a twenty-year veteran in the fitness industry, I have coached people from all walks of life as they begin, transform, & endure their individual journey to healthfulness. As an athlete in my youth, I fell in love with the beauty and intricacy of human movement and have lived through that passion ever since.

During my 20 years, I have been a personal trainer, group fitness instructor, bootcamp instructor, Master Trainer for Les Mills, manager of multiple group fitness programs and personal training programs, and have taught yoga & weight lifting at a community college. I have been featured in local papers and magazines and online forums promoting healthy living. I love it all. I simply enjoy watching people transform and realize their full potential as it is happening!

My absolute FAVORITE part of my work is my all-female F.I.E.R.C.E. program which has developed into a movement, a way of life. I coach both in-studio and online F.I.E.R.C.E. programs throughout the year and we have an absolute blast! My primary focus is coaching women to reconnect with themselves by prioritizing their health and finding the courage to be unapologetically all that they are, as they are.

You can find us in the Cross Garage Gym at 19 Tech Circle, Natick, Ma 01760.

What are SplitFit users saying?

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Laura B

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“I really like the flexibility of it. I’ve never actually been to a gym, so having access to a personal trainer-ish without the commitment is great. It was way less pressure to just sign up for one session where I wouldn’t be the only person and had a reason to show up at a gym.”

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Li S

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“I really liked the flexibility of not having to join the gym, but still getting access to work with high quality trainers. I’m a big fan of SplitFit and have shared the info with several colleagues and friends.”

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Nicola A

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“Thanks for the opportunity to provide feedback! I have been using the SplitFit app for work outs 3-4 times per week for over 6 months.”

How does SplitFit work?

Easily search trainers, gyms, and workouts based on your needs, schedule, and budget.

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Join a personal training pool, small group session, or book a private session with a trainer.

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Save on workouts with SplitBucks. Buy in bulk or earn SplitBucks for referring friends.

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Workout when it works for you. No memberships or commitments required.

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No membership required

From our Blog

  • New Sessions & New Trainers January 2021 - We added some great new trainers and sessions We are always excited to welcome new personal trainers on SplitFit and equally excited when our current trainers add new sessions. Here are a few updates for those of you in the Boston area.  Powerflex is a new workout from Julie DiLeo from WFOB. A primarily non-aerobic […]
  • Best Fitness Danvers photo Best Fitness Danvers Gym Review - About Best Fitness Danvers Best Fitness Danvers offers certified personal trainers who are dedicated to helping you meet your health and fitness goals with customized plans and programs. They offer fitness and nutrition programs that are individually created and that include everyone from beginner to expert levels. Location Best Fitness has several Massachusetts’ locations (Chelmsford, […]
  • Supplements and Pregnancy photo Supplements and Pregnancy: What’s Safe? (Part 2) - Last week we looked at some of the vitamins and minerals that are both needed and safe to take in pregnancy. This week we’ll look at a few more vitamins and minerals needed in pregnancy. Pregnancy places a heavy burden on a woman’s body. Everything seems to speed up: blood flow through the body, weight […]

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