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Diane Diefenderfer

Diane Diefenderfer, founder of Studio du Corps/Pilates Center of Orange County, is a second-generation Pilates teacher with over 35 years experience in the Pilates Method. She holds the honorable distinction of being awarded a Master Teacher Certification from legendary teacher and mentor, Ron Fletcher. She is PMA (Pilates Method Alliance) Gold-certified.


Diane enjoyed a 20-year career as a professional ballet dancer as a soloist with the Frankfurt Ballet, Eglevsky ballet and Los Angeles Ballet. A knee injury in 1978 first led her to discover the Pilates Method at the Ron Fletcher Studio of Body Contrology in LA where she spent the next 8 years studying and teaching. Diane also studied privately with Romana Kryzanowska.

In 1987, Diane opened Studio du Corps, introducing Pilates to Orange County, CA and 2 years later, founded the first Pilates program for the Dance Department at the University of California, Irvine. In addition to her extensive work with dancers, Diane has taught numerous Olympic athletes and figure skaters. In 2002, Diane began the Pilates program for the Human Resources Department for the City of Irvine. She has also taught mat classes at Irvine Regional Medical Center and for cancer survivors at Hoag Hospital. Diane has been a featured presenter at the Body Mind Spirit Conference and Pilates on Tour and continues to present workshops at Pilates Method Alliance conferences and Fletcher Pilates conferences. Diane’s work has been featured in the LA Times, O.C. Register, Sports Illustrated and Pilates Style Magazine. She is a Distinguished Faculty member for Pilates Anytime and part of the Legacy Project for the online site. Diane has given lectures at the Korean National University of Arts in Seoul, Korea and Tsukuba University in Japan. She is a contributing author to a book, Women’s Health and Wellness Across the Lifespan, published by Lippincott Williams & Wilkens. Diane conducts the Teacher Training Program at Studio du Corps (since 1995), proudly guiding and certifying the next generation of Pilates teachers.


Diane, Associate Professor of Teaching for the Claire Trevor School of the Arts, has been on the faculty of the UCI Dance Department since 1988. She teaches all levels of ballet technique, pointe and repertory as well as Pilates Mat and Reformer classes for the Dance Wellness Program.

Barbra Bean Abell

Barbra Bean Abell received her initial dance training in her native country, South Africa.  She performed professionally in a modern dance company, toured the country as a freelance dancer, and taught for numerous dance organizations. 

Upon immigrating to the United States, Barbra studied at both UC Santa Barbara and UC Irvine. At UCI she was introduced to the Pilates Method by Diane Diefenderfer.  After graduating UCI with a BA in dance she completed the Teacher Training Program at Studio du Corps.  She considers herself fortunate to continue on at the studio where she has been teaching and serving as studio manager for 20 years. 

She has also worked as Ms. Diefenderfer’s assistant at various workshops and was invited to teach at the 2015 Fletcher conference in Tucson, Arizona. Barbra studied extensively with Ron Fletcher as he held biannual workshops at Studio du Corps. Ron personally awarded her a qualified level teacher certificate in 2000 which pre-dated the formation of the current Fletcher program.


In 2015 she was a top 10 finalist in the Next Pilates Anytime Instructor competition and was featured in Pilates Style Magazine as a finalist. For the past 15 years she has worked as Ms. Diefenderfer’s assistant in the Teacher Training program at Studio du Corps coaching the trainees in the fundamentals of working with a wide range of clients in a safe and challenging environment.


Barbra currently teaches the Pilates work for the upper level students in the conditioning program at Maple Conservatory of Dance, one of Orange Counties premier ballet schools.  She has taught modern, jazz, Pilates mat classes and choreographed for several studios in Orange County including Ballet Pacifica for several years. She has served as guest faculty at several summer dance programs including Riverside Ballet, Southland Ballet, Ballet Pacifica and RNB Ballet School, Vancouver, British Columbia.

Valerie Hirst

Valerie Hirst, instructor at Studio du Corps since 1994, was a former manager and advisor on fitness and nutrition for an international health club, where she developed an awareness of and belief in the necessity of total mind/body integration in her approach to physical fitness. Valerie was trained and certified by her mentor, Diane Diefenderfer, at Studio du Corps. She has subsequently worked extensively with Master Teacher (elder) Ron Fletcher and is a certified instructor of the Ron Fletcher Work. Valerie brings to Studio du Corps 25 years of experience in the Pilates work and a desire to assist each client in reaching their fitness goals. She is a member of the Pilates Method Alliance and IDEA.

Niki Parker

Niki Parker, Certified in the Pilates Method in 2002, by Diane Diefenderfer at Studio du Corps.; attended several Pilates Method Alliance conferences, gaining additional training and became a PMA® Certified Pilates Teacher,  Niki teaches all formats of Pilates: group, mat and privates. With over 10,000 hours of teaching during the past 14 years, she enjoys sharing her enthusiasm for fitness and her passion for Pilates with every student, paying attention to detail and quality of movement in order to build a strong, flexible body.

Niki became a MELT Method Instructor in April of 2011; in  2012  she completed 7 days of MELT NeuroStrength training as an advanced instructor and is bringing this easy to learn technique of self-massage with small balls and a soft roller, to all of Orange County with over 8 classes a week.  She has continued with training in MELT for Pilates, using a soft half roller to better access the deep core.  She has also been a TA for Sue Hitzmann, the MELT Method Creator, for 4 recent workshops.   After earning a B.A. at CSULB and working full time, she became a Jazzercise instructor, teaching fun and effective dance classes for almost 24 years. She brings this wide-ranging background and her love of being fit to her Pilates and MELT instruction.

Suzanne Westmoreland

Suzanne Westmoreland, instructor, completed her certification in the Pilates Method under the direction of Diane Diefenderfer in August 2003. Suzanne has been a lifelong student of ballet and recognizes the benefits of Pilates to enhance dance training and maintain functional movement for daily life.

She has taught mat classes at various ballet studios throughout Orange County and continues to enhance her training by attending conferences and workshops. Suzanne has recently retired after 38 years in the field of education with the last twenty one spent as an elementary school principal.

Monet Sathre

Monet Sathre was born and raised in Thousand Oaks, CA where she grew up dancing with the Pacific Festival Ballet from 1997-2008. After moving to OC in 2008 to pursue her degree at UC Irvine, she met Professor Diane Diefenderfer in both her ballet and Pilates classes. While in college, Monet became a performer with Disney and used her Pilates training to manage and heal her dance injuries. She graduated in 2012 with a BFA in Dance Performance and a Minor in Business Management, then went on to complete the Pilates Teacher Training Program at Studio du Corps with Diane and Barbra in 2016. She teaches regularly at the studio as well as teaching in Dana Point and Lake Forest where she lives with her husband and 2 children. Pilates continues to improve her ability to be a well rounded, body aware performer in Disneyland’s Fantasmic!

Madi Thielman

Born in Northern California & raised in Las Vegas, Nevada, Madison Thielman began her movement journey at the young age of 3. Training extensively throughout the years in ballet, tap, jazz, hiphop, contemporary, ballroom, musical theater aerial silks. Since graduating high school Madi has been able to make a career for herself in the dance industry, beginning her professional work performing at numerous corporate events and benefits throughout the Las Vegas Valley. Madi went on to tour the country in Spirit Touring Production's “Broadway Christmas Wonderland” and has also performed internationally for RWS Entertainment Group and Holland America Luxury Cruise Lines.

Aside from dancing, Madi has taken particular interest in nutrition, fitness, and somatic practices such as Yoga and Pilates. After completing her 300 hour RYT Yoga certification through Trufusion and learning about the prestigious and extensive pilates training program at Studio du Corps, she decided to move to Southern California in order to further her knowledge in the Pilates practice. Madi is extremely grateful to be working with and learning from Diane Diefenderfer and Barbra Bean Abell. Upon concluding the teacher training program Madi has been offered the opportunity to join the Studio du Corps family as an instructor. She is excited to begin her career as a Pilates instructor at Studio du Corps and hopes to help enhance clients’ mind-body awareness, posture, flexibility and strength.

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Diane awarded the Master Teacher Certification by mentor Ron Fletcher