Changing the way people think about fitness!



Changing the way people think about fitness!



Please call us to schedule a tour


At its core, Body By X is in business to help people reach and maintain their fitness goals.  We think everyone and every BODY is unique and therefore everyone’s fitness program should be unique to them and their goals.  All of these great offerings come at a terrific price!  We believe everyone should have access to affordable exercise.  We created Body By X to meet the needs of those in our community who want a smaller, more personal space to work out.  We’re like no other fitness center, and we believe, as all of our members do, that we’re the best in Marin.


Xavier, and his wife Nadia, are the co-founders and partners of Body By X Skill Development & Training Center. Xavier has been a personal trainer, an architect of mind, body and soul for more than twenty years. His vision for Body By X was to create a space where kids and adults could overcome their physical and emotional fears and improve their self-esteem. 
From X...
Having been in the fitness field for almost 30 years, I’ve seen a lot of people come and go. I began my career on the sales side and quickly realized that just selling people memberships was not the way to help them achieve long term success.  I realized that people needed help beyond just signing a contract. It was at that point that I decided to become a personal trainer. Since then I have helped hundreds of people reach their goals and sustain a healthy lifestyle. Growing up with the lack of a good role model inspired me to become a good role model myself. This is why I gain such satisfaction coaching, training and mentoring kids. We’ve included 2 pieces of equipment at the Center, a leg press and an assisted pull-up sized for kids as young as 6 or 7 years-old.
Over the years, I have learned not just to listen but to really hear the needs of people of all ages. It’s this ability that helps me to encourage people to move beyond their perceived limitations. For example, I help women gain the strength to do exercises using their own body weight, including push-ups and pull-ups. It gives me great satisfaction to see the confidence this instills in them.
I opened Body By X with my wife, Nadia, to build a community of like minded people doing like minded things.  I feel that this kind of environment breeds success.  This is an aspect of Body By X that I believe our members truly treasure.
Nadia is a personal trainer and teaches an endurance indoor cycling class and Aerial Fitness!  She also manages the business side of Body By X including marketing and community outreach.  Nadia has worked in advertising, retail management and as a project manager for a software company.  She has a master’s degree in psychology and all of these experiences have prepared her well for gym ownership!
From Nadia…
Who am I?  Who I am today is a very different person than I was 10 or even 5 years ago.  I had never been to a gym before I met my husband and business partner, Xavier Jarrell, in 2006.  In fact, I guess you could say I was gym phobic!  I fancied myself as an outside exercise person, but my kids will tell you I was never really into exercise before X.  He inspired me to lift weights.  I hired him as my personal trainer.  And while I fell in love with him I also fell in love with weight training.  It’s one of the most empowering things I have ever done!  It has given me so much internal strength and confidence.  Enough confidence that this former gym phobic is now training others to help them reach their goals!
It’s the most rewarding work I have ever done and I am proud to have a business that inspires kids and adults to build strength physically and emotionally.
First and foremost, we are Mom and Dad, sharing sports and fitness with our children is one of our favorite things!  Please stop by our fitness center to say hello and learn more about our philosophy. 


Fitness Center Services

Fitness Center Services

Fitness Center Memberships & Classes - Personal Training - bioDensity

Infrared Sauna - Sports Group Training - Power Plate


Memberships @ Body By X Skill Development & Training Center:

A 1- year GOLD membership at Body By X includes:

FREE classes:

  • Aerial Fitness
  • Indoor Cycling
  • TRX
  • Restorative Stretch
  • Small Group Training
  • Pilates Mat class

Use of our:

An introductory session on our bioDensity device to increase the density of your bones, tendons and ligaments.

We have many membership options available.

Not interested in taking classes but prefer to work out on your own and use our state-of-the-art equipment, infrared sauna, Power Plate and more?  We have a membership option for you!

Email us @ info@getfitmarin.com

Not a member yet? Drop in for $20 a class or $25 to use all aspects of our facility and see how we're different from other fitness facilities in Marin County. We promise you'll love it! Be sure to check out our schedule to see when our fitness classes occur. We look forward to seeing you soon.


We have the best personal trainers in Marin County!  

You can view their profiles here. Personal training fees vary depending on the trainer and how many sessions you purchase. 

Personal Training Information

Please feel free to call us with any questions.



The Non-pharmaceutical solution for building bone and joint density.

The bioDensity system safely aids in increasing bone density by stimulating the body’s natural bone generation process.  Based on existing science of bone compression, bioDensity applies optimal biomechanics and increases density in bone, tendons and ligaments.

See the Video Below

The Surgeon General Chapter 9 States that increases in bone mineral density are stimulated by maximum loading of the musculoskeletal system.

Infrared Sauna Marin

Infrared Sauna Use @ Body By X Skill Development & Training Center

Body By X has the largest, commercial, infrared sauna in Southern Marin!

Infrared saunas have been proven to help with arthritis, detoxification, stress reduction, lowered blood pressure, weight loss, pain relief, improved circulation, psoriasis and other skin conditions, fibromyalgia and aging!

Recent research shows that increasing your core temperature for short periods, as is done by using a sauna, may offer dramatic improvements to your athletic performance. It does this using a concept called “hyperthermic conditioning”. It has multiiple positive effects on your body from increased endurance to the growth of new brain cells.

Email us @ info@getfitmarin.com if you have questions regarding our infrared sauna.


If you're considering introducing your son or daughter to training outside of his her sport please consider Body By X Skill Development & Training Center. Our trainers have years of experience successfully developing young athletes not just into better athletes but into young men and women who are stronger physically, mentally, and emotionally. We challenge them to grow on all levels. We teach them to respect themselves and others. We show them that exercise is a metaphor for life and we give them the discipline it takes to improve. We build well rounded student athletes. Our athletes learn to love exercise! Let Body By X help guide your young athlete on their journey.



As the global leader in whole body vibration technology, Power Plate redefines optimal health and wellness equipment for every age and ability.

Power Plates are engineered to apply the science behind the body’s natural response to destabilization. The Power Plate platform uses a consistent, safe and controlled level of vibration that moves in three directions (up and down, front and back, and side to side).

From rejuvenation and anti-aging treatments to rehabilitation and therapeutic massage, Power Plate provides exceptional results.

Whether you want to look better, feel better, or play better, Power Plate is the solution.

It’s not fiction—it’s science. More than 200 research studies conducted on whole body vibration have shown, when used regularly as part of a healthy lifestyle, Power Plate can help provide numerous wellness and fitness benefits, including:

Strength—   Improves muscle tone, builds explosive power and endurance.

Flexibility—   Increases range of motion, coordination, balance and stability.

Circulation—   Improves and increases blood flow to strengthen the cardiovascular system.

Weight Loss—   Reduces body fat and enhances metabolism.

Cellulite Reduction—   Diminishes the appearance of cellulite.

Alleviate Pain—   Promotes faster recovery of damaged muscles and tendons, decreases pain and improves joint function.


Fitness Classes

Fitness Classes

    Rhythm Ride with X - TRXtra - Rowing - StretchX - Aerial Fitness by N -
Aerial Play - Group X - Camp X - Fitness Rowing

Rhythm Ride With X

Indoor Cycling in Marin County

Are you ready to dance on a bike?  Xavier will take you on the ride of your life using the beat of the music and a kick ass stereo system to guide you!   You’ll ride the flats, do lots of mountain climbing and experience a range of speeds and resistance that will take you through all your training zones.  New to indoor cycling?  Don’t worry, this class is for EVERYONE.  The ONLY requirement is that you’re at least 4 foot 10.  You won’t want to take an indoor cycling class anywhere else after taking this one.  Seriously.  It’s that great.


TRX - Total Resistance Exercise

Straps.  Yep, straps.  Straps that provide a  full-body workout that will utilize your own body weight to help get you strong.  Created by a Bay Area ex-Navy Seal, these straps will kick your butt.  And if that’s not enough, the Xtra will having you stepping away from the straps long enough to use other aspects of the Center  to get that booty even stronger.   It's beginner-friendly but challenging enough for the fittest.  The best part.  Are you ready?  You determine how hard you want to go simply by changing the position of your body.  Nice for those days you’re feeling like a wimp and great for those days when you’re ready to conquer the world!

Fitness Rowing


An indoor rower provides a full body workout better than almost any other piece of exercise equipment. You control the effort of each stroke as you use the power of your major muscles to improve your cardio-conditioning. Indoor rowing builds cardio-endurance and muscular strength with a workout that tones and conditions your arms, quads, hamstrings, glutes and abs, all at the same time! New to rowing? No problem. We’ll start with the basics and move on from there. Experienced? We’ll review detailed rowing-stroke technique and good posture and form.  Get an all-around, non-impact, muscle-toning, endurance-building, fat-burning workout that can burn over 500 calories in less than 50 minutes.

Group X

New to strength training?  Never been to a gym?  Hate working out by yourself?  This class is for YOU!  It’s a small group-exercise program designed to help you gain strength, stability and flexibility.  Learn to use your own body weight, dumb bells, machines (yes those ugly gray pieces of equipment you’ve stared blindly at for years!) to get you in optimal shape.  You may even make some friends on your way to getting fit, woohoo!

Camp X

This boot camp style class will keep your heart rate up and the blues down!  Calling all injury free folks who want a fast paced, sweat producing workout, this one’s for YOU!  You’ll have a blast running through our agility ladder, jumping over hurdles, zipping through cones and pushing past your comfort zone.  Don’t worry, we’ll provide the towels. 


StretchX can help you: 

  • Strengthen core muscles
  • Improve your alignment and posture
  • Improve your balance & stability
  • Support the body to be free of injury
  • Improve flexibility, range of motion and ease of movement
  • Tone muscle and relieve muscle tension and soreness.

A MUST take class for anyone who exercises.  If you don’t take this class, someday you won’t be able to take any class.  That’s really all there is to say.  Oh, one more thing.  You’ll feel like a brand new person when it’s over.

Aerial Fitness by N

Join Marin County's Body By X Co-Owner, Nadia Mcclinton and take your fitness off the floor!

Fun?  Yes!  Challenging?  Hell yeah.  Aerial Fitness is a little bit of everything.  Simply put, it’s strength training in the air.  You’ll do tons of stretching too and your core will thank you when it’s over.  Great for stress relief and fun for ages 8 to 88.  If you’re looking for a different kind of workout, you just found it!  Pull-ups and push-ups will never be the same.

Aerial Play


Come hang with us! This "class" isn't really a class but an opportunity for beginners to learn Aerial basics and advanced participants to practice their moves!  Drop in anytime between 4 and 6 on Wednesdays.  Come on…haven’t you always wanted to try it?  Now’s your chance!



Open Mon – Fri
5 am – 9 pm  
Sat, 5 am – 7 pm
Sun, 5 am – 7 pm

Non Member Hours-
Please call for an appointment


Open Mon – Fri
5 am – 9 pm  
Sat, 5 am – 7 pm
Sun, 5 am – 7 pm

Non Member Hours-
Please call for an appointment


Body By X

5768 Paradise Dr.,
Corte Madera, CA 94925
Tel: (415) 945-9778


Mon-Fri, 5am-9 pm
Sat, 5am - 7 pm
Sun, 7am - 7 pm

Non Member Hours -
Please call for an appointment

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