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Instructor Trainer bios

The Merrithew Faculty, or members of our esteemed team of Instructor Trainers, is made up of highly qualified and internationally sought-after educators who are known for their dedication, professionalism and attention to detail. All of our faculty members hold full certification in the STOTT PILATES® method and have achieved additional designations to complement their training. A diverse group, they come from various backgrounds including physical therapy, exercise science, athletic therapy, dance and group and personal fitness training to name a few. Every member of the team strives to uphold the highest standards of training that have been developed worldwide.

Mary Jo Ketterhagen

Mary Jo Ketterhagen-Ida

John Garey Fitness & Pilates
Long Beach, California, USA

IT qualifications
STOTT PILATES® Matwork and Reformer, Cadillac, Chair and Barrels, ISP; ZEN•GA®, Total Barre®

Additional credentials and designations
ACE, PMA, Gyrotonic Certified, Gyrokinesis Certified, Bachelors of Science / Microbiology


Mary Jo has had a long history in the fitness industry, beginning in 1993 as an Aerobics Instructor. She first received her certification as a STOTT PILATES® Certified Instructor in 2002, and quickly moved on to become an Instructor Trainer for Merrithew specializing ZEN•GA® in 2013, Total Barre® in 2013 and is a Lead IT in STOTT PILATES®. Since becoming certified, Mary Jo has taught courses throughout the Unites States, and internationally as well. In addition to her STOTT PILATES® Certification, Mary Jo is also a certified White Lotus Yoga Instructor and a Mad Dogg® Spinning Instructor. She specializes in creating workouts for all fitness levels and helping each of her clients to reach their fitness goals.

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