Personal Training at the Center

Are you interested in losing weight? Getting into shape? Building more muscle mass? Gym personal training sessions can help you stay focused on your exercise regimen and build strength, endurance and confidence. Body By X puts the fun back into going to the gym!


Xavier McClinton:

Xavier has been a personal trainer for over 25 years, successfully helping hundreds of people reach their fitness goals. His clients have lost weight, competed in marathons and triathlons, won masters rowing events and become key players in basketball, football, soccer, lacrosse, tennis, volleyball and baseball. A former athlete himself, Xavier knows what it takes to be competitive. He also knows the importance of safety. He created JUMP Training Marin, an injury prevention program designed to teach young athletes how to compete efficiently, effectively and safely. Xavier is passionate about making good athletes great and helping everyone reach their fitness goals.


Nadia McClinton:

Nadia is grateful to be in the business of helping women reach their fitness goals! As co-owner of Body By X, she spent her first few years here managing the business side of things. She watched our trainers change people’s lives and decided she wanted to do the same. Wow is she glad she did! Nadia has helped her clients lose weight, tone muscle and gain strength, others to build stronger bones (via our bioDensity device) and some get a bigger butt (yes, big butts are finally in!).  Nadia is encouraging and thoughtful in the custom workouts she creates to help her clients reach their goals.


After nearly 20 years as a personal trainer, and with a nod to his graduate degree in clinical psychology from Pepperdine University, every workout with Charles Walz begins with a simple question, “How do you feel today?” It’s a personal approach designed to not only discover how his clients’ feel physically, but mentally, as well.  As Charles explains, “Each workout should not only help strengthen the bodies, but also the minds and spirits of my clients. Discovering, first and foremost, how my clients are feeling helps to set the tone for our time together. We all feel differently each day and I want to ensure that the workouts are tailored for maximum benefit—whether my clients feel great and have their A-Games, or maybe need a bit of a pick-me-up.” Upon this check-in, Charles incorporates flexibility, cardio and muscle strength/endurance to craft a multi-faceted, custom workout that targets each client’s individual goals and objectives. Bringing best practices expertise to his work, Charles is certified as a Personal Trainer from the prestigious American College of Sports Medicine with enhanced certification in Advanced Personal Training and Exercise and the Older Adult. He has also been certified as a Group Instructor for Spinning and TRX and as an Emergency Medical Technician (EMT-I).

Out of the gym, Charles can be found feeding his passion for the backcountry—backpacking, climbing, snowshoeing and/or cross-country skiing. He’s also never one to miss a long motorcycle tour or good live music.

John Spongberg:

John has been professionally educating, empowering, and coaching clients for over 12 years. He started in the health and fitness field as a personal trainer while attending college where he realized his passion for helping others and transforming clients’ lives.

John's philosophy:  “I am an avid learner and I’m always looking to improve and become a more effective teacher and educator.  Being a good listener and asking the right questions has enabled me to effectively coach and educate clients while exceeding expectations. There are many challenges you face each and every day, but when you really get down to the heart of the matter...are you growing and learning each day?  Are you challenging yourself to your full capability? If you’re not, I suggest you’re stagnant and stagnant means you are unnecessarily suffering. I have committed my life to helping others and empowering clients to improve themselves and their quality of life. We can all make substantial differences and improvements in our lives and in the lives of our families and friends. I help people move and feel better in their everyday life whether that means helping you to remain strong and independent with your life, or incorporating sport specific drills that improve skill levels for your sport of choice. Everyone has their own idea of improving their health and fitness. I promise to listen and design a fitness protocol, or implement a nutritional program that is individualized and effective. I will provide the most comprehensive up to date assessment, evaluation, and fitness practices that are available in the field today."

John founded Personal Training In Marin (PTIM) and regularly blogs fitness tips and wisdom. He is nationally certified by the American College of Sports Medicine as a Health/Fitness Specialist and by the National Strength and Conditioning Association.

Oliveyah Salvage:

Oliveyah is a the leading expert in the health and fitness industry. She has a masters degree in Exercise Science and holds certifications for personal training and performance enhancement through NASM.  She is a black belt in Kung Fu San Soo and started participating in group classes at age four.  Quickly after, she began demonstrations and exhibitions for the International Kung Fu San Soo Association. In addition to her martial arts background, she also grew up playing and coaching competitive volleyball, along with basketball, track and field. After receiving her B.A in Sociology from the University of California, Santa Cruz in 2005, Oliveyah moved to the San Francisco Bay Area as an accredited yoga teacher and started teaching classes in San Francisco and Marin County.  Shortly after, she began working as a certified personal trainer, creating a training program designed to meet the unique needs and lifestyle of Marin's upper income and time challenged residents. Oliveyah develops programs for people who prefer to workout in small groups or individually with a personal trainer; her programs include outdoor boot camp training, slow-protocol strength training, yoga and custom programs that meet the needs of all fitness levels and ages.


As founder of A2 Peak Performance, Andre developed a love for fitness at a very young age.   Growing up, he had the opportunity to work with a variety of different personal trainers throughout Los Angeles County, eventually earning a Division 1 football scholarship to UC Davis in 2009.  At Davis, Andre was a 3x Team Captain and 6x Scholar Athlete, developing his leadership skills throughout his career.  During his college years, Andre made the most of his opportunity by training other college students and residents in the area, all while training to reach his own athletic potential.  After Graduation, Andre continued to pursue his dreams of becoming a full-time personal trainer by working with some professional athletes, but commits most of his time to men and women who want to burn fat, get stronger, and tone up.

As a result of his journey, Andre designs workouts with the idea that "Workouts should be FUN, FAST, and EFFECTIVE" in mind.  His Circuit-Style Functional Training is unique because it maximizes client abilities to complete everyday tasks, while helping them get stronger, burn fat, and tone up.  Andre guarantees that if you train with him, you will develop motivation and a confidence within yourself that you've never seen before!  

So there you have it…  Now come in, get motivated and get in shape!

Rian Spalding

Rian is a graduate of the National Personal Training Institute and holds Personal Training, Kettle Bell and Nutritional certifications.  He has extensive background in sports and utilizes the National Sports Conditioning Associations’ guidelines in designing goal specific programs for the following populations: adolescents, overweight, morbidly obese, elderly, injury prevention and various athletes ranging from rock climbers to track and field.

Rian has a deep dedication to sports, fitness and nutrition, and uses his knowledge and experience to develop programs that cater to individual goals.  His clients get the results they want and more!