Pilates Core Exercises on the Reformer: A Full Guide

The Reformer Changed Everything I Thought I Knew About Core Work

Why pilates core exercises on a reformer build strength that mat work alone never will

Most people walk into my studio along the Wasatch Front thinking they already know what core work feels like. Sit-ups. Planks. Maybe a few twisting crunches. Then they lie down on the reformer carriage, and within ten minutes, their whole understanding shifts. Pilates core exercises on a reformer are a completely different language — one your body has probably been waiting to learn. The springs create resistance. The moving carriage creates instability. And between those two forces, your deep stabilizing muscles have no choice but to wake up. I’ve been teaching this work for years in my Salt Lake City studio, and I still find it endlessly fascinating how the reformer reveals what the core actually is — and what it’s been missing.

What Makes Pilates Core Exercises on a Reformer Different

Here’s the simplest way I can explain it: on the mat, you move against gravity. On the reformer, you move against springs and gravity, while the surface beneath you is also moving. Your core has to manage three variables simultaneously — force, stability, and control.

That’s the magic. That unstable carriage requires constant engagement from your transverse abdominis, your pelvic floor, your multifidus — the deep muscles that don’t get credit on Instagram but are responsible for protecting your spine every single day.

Joseph Pilates developed the reformer in the early 20th century, originally calling it the “Universal Reformer,” and it was designed with exactly this principle in mind: resistance that teaches control. Not just strength. Control. He called his entire method “Contrology,” and the reformer remains the most powerful expression of that philosophy.

The Core Is Not Just Your Abs — And the Reformer Proves It

One thing I see constantly with new clients — especially those coming from a gym background here in Draper or Sandy — is the belief that core training means abdominal training. They want to feel “the burn” in their six-pack muscles. And sure, the rectus abdominis matters. But it’s the outermost layer. It’s the flashy muscle. The real architecture lives underneath.

Your core is a cylinder. The diaphragm is the roof. The pelvic floor is the base. The transverse abdominis wraps around the front and sides like a corset. The multifidus runs along the spine in back. When all four walls of that cylinder work together, you have true stability. When one wall is weak or disconnected, the whole system compensates.

The reformer has an uncanny ability to expose those compensations. I had a client last year — a trail runner from Cottonwood Heights, strong legs, strong will — who couldn’t keep the carriage still during a simple footwork series. Not because she was weak. Because her deep stabilizers didn’t know how to coordinate. Within six weeks of consistent reformer classes, she said her running felt “quieter.” Her low back pain had disappeared. Nothing in her training had changed except the Pilates.

My Favorite Pilates Core Exercises on the Reformer

I want to share some of the exercises I return to again and again in my teaching. These aren’t the only ones — the reformer repertoire is vast — but these are the ones I see create the biggest shifts in core awareness and strength.

1. The Hundred (Reformer Variation)

You know The Hundred from mat class. On the reformer, your legs are in the straps and the springs are light. Your legs are suspended, not resting on anything. Your arms pump. Your breath drives the rhythm. But your deep core has to hold everything still while your limbs create movement and momentum. It’s a completely different challenge than the mat version — less about endurance, more about precision.

2. Knee Stretches (Round Back)

This is one I love for clients who sit at desks all day — and living along the Wasatch Front, between the tech corridor in Lehi and the offices downtown in Salt Lake City, that’s a lot of people. Kneeling on the carriage, hands on the footbar, spine rounded into deep flexion. You push the carriage out with your knees and pull it back in using your lower abdominals. The spring tension demands that you control the return. No momentum allowed. It’s humbling and brilliant.

3. Long Stretch

Think of a moving plank. Hands on the footbar, feet on the shoulder rests, body in a straight line. You push the carriage away and pull it back. Every second of this exercise requires full-body integration, but the epicenter of control is your core. If your trunk sags or hikes, the carriage tells on you immediately.

4. Short Spine Massage

This one surprises people. It feels luxurious — almost like a stretch — but the articulation of the spine on the return requires deep eccentric control from the abdominals. Rolling down through each vertebra with your feet overhead, springs pulling you, carriage sliding beneath you. Your core is working the entire time, even if it doesn’t feel like “work.”

5. Coordination

Arms in straps, head and shoulders lifted. You extend your arms and legs simultaneously, open-close the legs, bend everything back in. The timing is everything. The springs want to snap your arms back. Your core has to hold the trunk completely stable while four limbs are in motion. It’s small. It’s intense. It’s one of the most effective core exercises on the reformer, period.

Why Spring Tension Matters More Than You Think

Not all springs are created equal, and more resistance doesn’t always mean a harder workout. This is something I spend a lot of time educating clients about. For core-focused reformer work, lighter springs are often more challenging because they provide less support. Your stabilizers have to work harder to control the movement.

Think of it this way: a heavy spring holds the carriage steady for you. A light spring says, “You figure it out.” The deep core muscles are the ones that figure it out.

This is also why working with a trained instructor matters. The wrong spring setting won’t just make an exercise less effective — it can shift the load into your hip flexors, your low back, or your neck. I’ve seen clients come from other studios frustrated because their neck always hurt during ab work. Nine times out of ten, it’s a spring issue — or a cueing issue. The exercise itself isn’t the problem. In our Alchemize classes, I’m constantly adjusting springs and cues to match each body in the room.

Core Strength Is Not Core Control — The Reformer Teaches Both

Strength is the ability to generate force. Control is the ability to manage it. You can be strong and still lack control. I see this all the time — strong athletes who can deadlift heavy but can’t stabilize a neutral pelvis on a moving carriage. The reformer doesn’t care how much you can lift. It cares about how precisely you can move.

This distinction is why reformer Pilates has become so important for rehabilitation and injury prevention. Physical therapists across Utah County and the Salt Lake Valley increasingly recommend it for clients with low back pain, diastasis recti, SI joint dysfunction, and postpartum recovery. The reformer creates a controlled environment where you can load the core progressively without the impact or compression of traditional strength training.

And that’s the beauty of the method. Whether you’re a postpartum mother in Sandy rebuilding her deep core, a skier in Park City wanting better trunk rotation, or someone in Draper who just wants to move without pain — the reformer meets you exactly where you are.

How Often Should You Practice Reformer Core Work?

In my experience, two to three sessions per week is the sweet spot for most people. That’s enough frequency for your neuromuscular system to build new patterns without overdoing it. Pilates — especially on the reformer — is designed to be sustainable. Joseph Pilates himself said, “In 10 sessions you’ll feel the difference, in 20 sessions you’ll see the difference, in 30 sessions you’ll have a whole new body.”

I’ve watched that timeline play out hundreds of times in my studio. The first few sessions are about learning the machine and the language of the work. By session ten, clients start noticing they’re standing taller, breathing deeper. By session twenty, the changes are visible. Waistlines shift. Posture transforms. And the core — that deep, quiet, powerful cylinder — becomes something they can actually feel and access throughout their day.

If you’re ready to experience this for yourself, I’d love to have you. You can book your first session here and feel the difference a reformer makes.

The Honest Truth About Pilates Core Exercises on a Reformer

I’ll be transparent. The reformer isn’t the only way to build a strong core. Yoga works. Strength training works. Even mat Pilates — done well, with good cueing and intention — works. I’m not here to tell you everything else is wrong.

But I will say this: in over a decade of teaching, I have never seen anything match the reformer’s ability to create core awareness. The feedback is immediate. The springs don’t lie. And when the deep stabilizers fire correctly — when the whole cylinder engages as a unit — you feel something you’ve never felt before. Not a burn. A connection. A quiet, anchored power that changes how you walk, how you sit, how you breathe.

That’s what pilates core exercises on a reformer offer. Not just a stronger midsection. A smarter one. A body that understands itself. And for my clients along the Wasatch Front — from Lehi to Salt Lake City — that understanding changes everything.

— Bianca

Bianca — Founder, Alchemize Pilates

Bianca is a certified Pilates instructor and the founder of Alchemize Pilates, a boutique reformer studio in Utah serving clients across the Wasatch Front. With over a decade of teaching experience and advanced training in classical and contemporary Pilates methods, she specializes in helping people build deep core strength, recover from injury, and move with more ease and intention. Book a session with Bianca →