What Muscles Does Reformer Pilates Work? Full Guide

What Muscles Does Reformer Pilates Work? A Full-Body Breakdown from a Utah Instructor

Every spring, every carriage slide, every breath — it all adds up to something remarkable.

If you’ve ever watched someone on a reformer and thought “that looks too elegant to be hard,” I need you to reconsider. One of the most common questions I hear from new clients walking into my studio along the Wasatch Front is: what muscles does reformer Pilates work? The honest answer surprises most people. It’s not just your abs. It’s not just your glutes. Reformer Pilates works your entire body — from the deep stabilizers wrapped around your spine to the muscles in your feet you’ve forgotten existed. And it does it in a way that’s intelligent, progressive, and unbelievably efficient.

I’ve been teaching reformer Pilates in Utah for years, and I still find myself marveling at how one machine can challenge a marathon runner and a total beginner in the same class. Let me walk you through exactly what’s happening in your body when you step onto the carriage.

What Muscles Does Reformer Pilates Work? The Short Answer

That’s the quick version. But “full body” is vague, and you deserve better than vague. Let me break this down muscle group by muscle group — the way I explain it to my clients in Salt Lake City, Sandy, and Draper when they first lie down on the reformer.

The Core: Your Deepest Layer of Strength

When people hear “Pilates,” they think “core.” And they’re right — but not in the way they expect.

Joseph Pilates, who developed this method in the 1920s, called the core the powerhouse. He wasn’t talking about a six-pack. He was talking about the deep, invisible muscles that stabilize your spine and pelvis: the transverse abdominis, the multifidus, the pelvic floor, and the diaphragm.

On the reformer, these muscles never get a break. The moving carriage creates an inherently unstable surface. Your body has to stabilize against the springs with every single movement. A footwork series might look like a simple leg press, but underneath, your deep core is firing constantly to keep your pelvis neutral and your spine steady.

Then we layer in exercises that directly target the superficial core: the rectus abdominis (your “six-pack” muscle), the internal and external obliques, and the erector spinae running along your back. Exercises like the Hundred, short spine, and coordination series light these up with a precision that crunches simply can’t replicate.

I see this with my clients who come to us after years of gym work — they’re strong in isolated movements, but the first time they try to control the carriage while holding a plank variation, they realize there’s a whole layer of strength they never built. If you’re curious how the reformer stacks up against traditional gym workouts, I wrote a detailed comparison of reformer Pilates vs. the gym that digs into this.

Glutes and Hips: Where Power Meets Stability

Your glutes — the gluteus maximus, medius, and minimus — are some of the biggest beneficiaries of reformer Pilates. And honestly? They’re some of the most neglected muscles in modern life.

If you sit at a desk in Lehi or commute down I-15 to Utah County every day, your glutes are likely underactive. The reformer wakes them up. Exercises like bridging with feet on the footbar, standing side splits, and single-leg pressing demand that your glutes not only produce force but also stabilize your hip joint and pelvis.

The hip flexors (particularly the psoas and iliacus) get both stretched and strengthened. The same goes for the hip adductors and abductors — the inner and outer thigh muscles that control lateral stability. Exercises on the reformer constantly challenge these muscles through their full range of motion, which is something I rarely see replicated on standard gym equipment.

One client of mine — a snowboarder from Park City — was floored by how much her hip stability improved after two months of consistent reformer work. She told me her turns felt more controlled than they had in years. That’s what happens when you build strength in the muscles that stabilize you, not just the ones that move you.

Legs: Quadriceps, Hamstrings, and Calves Under Spring Tension

The reformer is essentially a horizontal leg press with a twist: the resistance comes from springs, which create variable tension throughout the entire range of motion. This changes everything.

Your quadriceps fire during footwork, lunges on the platform, and any exercise that involves pressing the carriage away from the footbar. But unlike a standard leg press machine, the springs also demand eccentric control — meaning your muscles work just as hard (sometimes harder) on the return. This eccentric loading is where real strength and muscle resilience are built.

Your hamstrings are engaged in pulling movements, bridging variations, and single-leg work. They also act as stabilizers whenever your glutes are working, which on the reformer is almost always.

And don’t forget the calves — the gastrocnemius and soleus. We do heel raises, relevés on the footbar, and jumping board work that challenges the lower leg in ways that translate beautifully to running, hiking, and skiing. Living along the Wasatch Front, so many of my clients are active outdoors. The reformer makes their legs ready for whatever the mountains throw at them.

Upper Body: Shoulders, Arms, Chest, and Back

Here’s where people are most surprised. Yes, the reformer works your upper body — and it works it well.

The latissimus dorsi, rhomboids, and trapezius are engaged through pulling strap exercises. When you lie on the carriage and pull the ropes toward your hips or overhead, you’re building back strength that directly counters the rounded-shoulder posture so many of us carry from working on laptops and phones.

The deltoids and rotator cuff muscles are challenged through arm circles, overhead pressing, and plank-based work on the reformer. Because the springs provide resistance through the full range, the rotator cuff has to stabilize the shoulder joint the entire time — not just at the peak of a movement.

Your chest (pectoralis major and minor) is targeted through pushing movements — think pressing out from a kneeling position or performing chest expansion exercises. The triceps and biceps work as synergists in almost every upper-body exercise, building lean, functional arm strength.

In my studio, I often use the strap work as an opportunity to address muscular imbalances. Many of my clients in Sandy and Cottonwood Heights come in with one shoulder noticeably tighter or weaker than the other. The reformer lets us isolate, correct, and rebuild symmetry in a way that’s controlled and safe.

The Muscles You Can’t See: Stabilizers and Deep Postural Muscles

This might be the most important section of this entire post.

Reformer Pilates doesn’t just work the muscles you can see in the mirror. It works the invisible architecture that keeps you upright, balanced, and pain-free. The multifidus muscles along your spine. The deep cervical flexors in your neck. The serratus anterior that stabilizes your shoulder blades. The intrinsic foot muscles that support your arches.

These are the muscles that physical therapists obsess over. And they’re the muscles that the reformer trains beautifully — because the spring-based system demands constant stabilization, not just brute force.

This is also why reformer Pilates is so frequently recommended for injury rehabilitation, prenatal and postpartum fitness, and chronic pain management. It builds you from the inside out. If you’re brand new to the reformer and not sure what to expect, my beginner’s guide to your first reformer class will walk you through everything — from what to wear to what it actually feels like on the carriage.

Why the Reformer Works Muscles Differently Than Other Workouts

Let me be clear: I’m not anti-gym. I’m not anti-running. I’m not anti-anything that gets you moving. But the reformer works your muscles in a fundamentally different way, and it’s worth understanding why.

• Variable spring resistance means your muscles are loaded differently at different points in the movement, which builds strength through a complete range of motion.
• Eccentric emphasis — the controlled return of the carriage — strengthens muscles in their lengthened position, reducing injury risk and building flexibility alongside strength.
• Closed-chain and open-chain exercises are both possible on the reformer, meaning you can mimic everyday functional movements and isolate specific muscles in the same session.
• Low impact, high demand — the reformer challenges your muscles intensely without the joint stress of heavy lifting or high-impact cardio. This is especially valuable as we age or recover from injury.
• Whole-body integration — even “leg” exercises require core engagement, and “arm” exercises demand hip stability. Nothing works in isolation.

This is what makes reformer Pilates more than just another workout. It’s a practice. And it’s one I’ve watched transform bodies all across Utah — from college athletes in Provo to retirees in Draper who just want to pick up their grandkids without pain.

How Often Should You Do Reformer Pilates to See Results?

I recommend 2-3 sessions per week for most people. Consistency matters more than intensity. After about 6-8 weeks of regular practice, most of my clients notice significant changes: improved posture, stronger core engagement in everyday activities, less back pain, more defined muscles — especially in the glutes, legs, and arms.

Joseph Pilates himself said: “In 10 sessions you will feel the difference, in 20 you will see the difference, and in 30 you will have a whole new body.” In my experience teaching along the Wasatch Front, that timeline holds remarkably true.

If you’re ready to feel it for yourself, take a look at the class schedule at Alchemize Pilates. We keep our classes small so I can actually see you, cue you, and make sure every muscle that should be working is working.

The Bottom Line: What Muscles Does Reformer Pilates Work?

All of them. Genuinely.

When someone asks me what muscles does reformer Pilates work, my answer is always this: the reformer works every major muscle group in your body — your core, glutes, quads, hamstrings, calves, back, shoulders, chest, and arms — plus the deep stabilizer muscles that most workouts never touch. It builds strength, flexibility, balance, and body awareness simultaneously. It is, in my honest and experienced opinion, one of the most complete forms of exercise you can do.

And it’s waiting for you right here in Utah.

— Bianca

Bianca

Founder & Lead Instructor, Alchemize Pilates

Bianca is a certified Pilates instructor and the founder of Alchemize Pilates, a boutique reformer studio serving the Wasatch Front. With years of experience teaching clients of all levels — from total beginners to competitive athletes — she’s passionate about helping people build strength, heal their bodies, and move with confidence. She lives in Utah and can usually be found on a reformer, on a trail, or drinking an oat milk latte between classes.