Pilates Reformer Springs Guide: Types, Resistance & How Many

Why Your Springs Feel Soft (and What to Do About It)

Last fall, a studio owner in New York emailed our factory. Her question was short: “Why do my springs feel softer than the day I bought them?”

She had run the same reformer for 18 months. Six classes a day, five days a week. The light spring on her favorite machine no longer felt light. It felt dead.

That email started a conversation we have almost every week. Most buyers choose a reformer for the frame, the wood, the price. Then they never think about the springs again. Until something feels off.

This guide covers what we tell those owners, and what we test on our own line every day: spring types, resistance levels, how many springs a machine ships with, and when to replace them.

Spring Types: Light, Medium, Heavy, Extra Heavy

Pilates reformer springs come in four standard resistance levels. Color coding varies by manufacturer, but the most common system looks like this:

• Light (red). The lowest resistance. Used for arm work, footwork warm-ups, rehab clients, and beginners who are still learning to control the carriage.
• Medium (blue). The workhorse of the machine. Most footwork and core exercises run on one medium spring, sometimes paired with a light.
• Heavy (green). For leg presses, lunges, and stronger clients. A heavy spring gives clear feedback on push-offs and lowers.
• Extra heavy (black). Maximum resistance. Reserved for advanced strength work and athletes who need a genuinely hard pull.

Resistance is measured at full stretch. A typical light spring pulls around 10 to 12 kg when fully extended. A heavy spring can reach 22 to 25 kg. The numbers vary between factories, which is why you should always test a machine before you buy it, not just read the sticker.

How Resistance Works: Count the Springs

There is no gearbox under a reformer. No dial, no button. The resistance is simply the number of springs you hook up.

One spring stretches and pulls back. Two springs double the pull. Three springs change the ride completely. The carriage stiffens, the glide shortens, and every push requires real intent.

Instructors use this in every class. Footwork often runs on two springs. Arms and upper-body work run lighter, sometimes on a single light spring. The system is purely additive, and that is why the springs matter more than any other part of the machine.

How Many Springs Does a Reformer Ship With?

A standard studio reformer ships with four springs: one light, one medium, one heavy, and one extra heavy. Many manufacturers, including us, ship five. The fifth is usually a second medium spring.

Why five? Because the most common combos are light plus medium for footwork, and medium plus heavy for leg work. A spare medium spring gives instructors more combinations without swapping hardware between classes.

Tower machines change the math. A reformer with a tower attachment carries extra springs for the push-through bar and the roll-down bar. Those units usually ship with six to eight springs in total. If you run a mixed studio, keep a spare set of each weight on the shelf.

Home users can trim the set. A foldable reformer for a spare room usually does fine with two or three springs, because home sessions run lighter and shorter. Studio machines are a different story: they get used from morning to night, so they need the full set plus spares.

Spring Aging: What Our Factory Test Bench Shows

Every spring that leaves our line goes through a cycle test. The rig pulls the spring to its rated stretch and holds it. Then it does it again. And again. Thousands of times.

A new spring snaps back with full force on cycle one, and it stays close to that for most of its working life. Then it fades. Springs do not break loudly. They weaken quietly.

We also run load tests far beyond studio conditions. Our bench can pull more than 500 kg on a single hook, far past anything a client will ever apply, to confirm the steel holds and the hooks stay true. That test finds weak coils before they reach your studio, and it tells us how long a properly built spring should last.

For a studio machine in daily use, plan on replacing springs every 18 to 24 months. Home machines can run three to four years. Watch for these signs:

• The carriage drifts back on its own when you release it. The spring has lost tension.
• One machine feels noticeably different from the same model next to it.
• You spot rust, kinks, or an uneven gap between coils.
• The spring sings a metallic “zing” at full stretch.

Any one of those means the spring needs to go. Do not wait for a visible break. A snap mid-exercise can injure a client, and it can scar a frame you paid real money for.

Factory Buying: What to Check Before You Order Springs

If you are sourcing reformers for a studio chain or a wholesale program, spring quality is where you win or lose. Cheap springs are drawn from lower-grade steel. They fade in months, not years.

Ask every supplier three questions:

1. What steel grade is used in the spring wire?
2. What load test do springs pass before shipping?
3. Can you supply replacement spring sets for the machines you sell?

OEM buyers go further. Many of our wholesale partners order springs with their own color coding, or custom resistance curves tuned to their training system. We set the production line to match, so every machine in their fleet pulls the same. Tell us your spec, and the springs leave the factory with your label on the set.

Here is the test we recommend before signing anything: put a brand-new machine on the bench and pull it against a unit that has seen five thousand workouts. The difference in spring feel tells you more than any spec sheet.

Frame choice changes spring feel too. A solid maple wood reformer pairs strong springs with a carriage that glides without binding. A lighter WT aluminum reformer responds faster underfoot, which some coaches prefer for speed work. What matters is that the spring, the carriage, and the rail are matched to each other. That match is the machine.

Maintenance That Keeps Springs Alive

Springs fail early when they are abused. A few habits change that:

• Wipe springs down after sweaty classes. Sweat is salt, and salt eats steel.
• Leave springs relaxed when the studio closes for the night.
• Check hooks and retaining pins weekly. A bent hook fails under load.
• Keep the carriage wheels and rail lubricated. Run springs dry.
• Rotate spring positions when you can, so one spring does not take all the wear.

Springs are the smallest part of a reformer and the easiest to overlook. They are also the part your clients feel on every single rep.

Choose the Right Springs, and the Machine Will Last

A reformer is a frame with springs underneath. That is the whole machine. The springs are the workout: the resistance, the feedback, the control.

Pick springs for what your clients actually do. Beginners and rehab clients need light and medium weights. Strength programs need heavy and extra heavy. And buy from a factory that tests springs the way a studio uses them: hard, and often.

If you are opening a studio, expanding a chain, or sourcing OEM machines for wholesale, our factory team can spec the spring set around your training style. We build reformers for studios across North America, Europe, and Australia, and every unit is tested before it ships.