Is This You?

You’re a group fitness instructor who…

  • Feels the strain of teaching high-impact classes day after day
  • Wants to add a gentle, powerful stretch class to your offerings
  • Dreams of a class that supports your body as much as your students’
  • Wants to attract and retain clients who value mindful movement


If this sounds like you, you’re not alone. Many instructors just like you have found this course a game changer.

  • Lying hip stretch
  • Shoulder stretch

What You'll Learn

  • How to cue, structure, and lead a full-length stretch class
  • The science behind effective flexibility training—what works and why
  • Techniques that reduce stiffness, increase mobility, and feel amazing
  • Common mistakes to avoid when teaching stretching to groups


Whether you’re teaching active older adults, beginners, or fellow instructors—this course gives you the tools to lead confidently and safely.

Take a Peek Inside

  1. Module 1 - Introduction

  2. Module 2 - Getting Started

  3. Module 3 - The Certificate Process

  4. Module 4 - Quick Reference

  5. Module 5 - The Basics

  6. Module 6 - Factors Affecting Flexibility

  • 113 lessons
  • Choose from self-paced to private coaching.
  • Learn a full flexibility class
  • Incorporate mini segments into your current classes

Who Is This Course For?

✅ Group fitness instructors ready to expand their class offerings. ✅ Instructors who want to move and teach in a way that feels sustainable long-term. ✅ Those looking for a low-impact class format that’s still effective and meaningful. ✅ Teachers who care about offering safe, intelligent movement to clients of all ages.
People stretching in an Extensa class

Choose Your Path

Whether you prefer to learn at your own pace or want personalized guidance, there’s an option for you.

🎯 Self-Paced with Private Coaching

$449

💻 Self-Paced

$249
  • Everything in the self-paced option, plus:
  • Four weekly 1:1 private sessions with Sarah
  • Personalized support, feedback, and mentorship
  • Complete the course on your own schedule
  • Step-by-step videos and downloadable guides
  • Start teaching stretch classes with confidence

Success Stories from Fitness Professionals Like You

“I am so glad to have found Extensa as I wanted to add a stretch class to my teaching skills. I thought I could probably wing it but in the end I decided to take a certification anyway. And I'm glad I did! ...I've also learned so much about the human body and it's made me a better instructor no matter what format I teach. I loved the program so much I became a master trainer!”

Melanie B

“I love the balance Extensa brings to my life. While teaching it, I find it so beneficial to myself as well as my participants...and I really feel that it has helped prevent injuries throughout my high diving career.”

Lysanne R

“Extensa has allowed me to better connect with my body and have more control over my movements...which makes it an even more effective workout compared to the traditional stretching class I attended before I became an Extensa instructor. Teaching it is also a unique experience and participants are very satisfied with the benefits they feel after the class”

Cynthia L

Why Choose This Course

This course was designed by Sarah Feilders, a flexibility expert with 25+ years in the fitness industry. Sarah has worked with Olympic athletes, high-performance teams, and everyday fitness enthusiasts to increase mobility, improve regular movement patterns and gain competitive flexibility. Now, she’s sharing her proven methods with fitness professionals like you.

Unlike generic flexibility courses, this specialty course is designed for fitness instructors. It gives you: ✅ A structured, teachable system—so you can confidently lead a class right away. ✅ Easy-to-follow class plans—no more second-guessing what to teach. ✅ A self-paced format—learn at your own speed and start implementing immediately.
Learn More About Sarah