Merz Built Fitness was founded with one mission: to create a private training space where performance, community, and consistency come together to empower every member. Founded by IFBB Pro and Certified Personal Trainer Billy Merz Jr. and his fiancée, Joanna Principato, our Linden-based facility offers a calm, focused environment designed for busy adults who want real results.

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Whether your goal is weight loss, building strength, improving overall health, or simply finding a comfortable place to start (or get back into a routine), we’ve built the foundation to support your success.

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We also offer personalized 1:1 personal training services focused on proper movement, functional strength, and results-driven programming—so you’re not just working out, you’re training with purpose. Our team is here to guide you, support you, and help you stay consistent for the long term.
 

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