Mechanics & specs
Pilates reformer springs explained
The short answer
Reformer springs provide resistance that increases as they stretch. Most machines carry four or five springs in two to four tension grades, color-coded by the manufacturer. There is no industry-standard color system, so a red spring on one machine may be a different resistance on another.
Color codes are brand-specific, not universal
This surprises people moving between studios. One manufacturer’s red might be its heaviest spring; another’s might be a light. There is no standard, and there is no reliable conversion between brands.
What is consistent is that manufacturers publish the tension grades for their own system. Learn your machine’s system rather than assuming a color means the same thing everywhere.
Why combinations matter more than count
A machine with five springs in four grades offers far more usable settings than one with five springs in two grades, even though both advertise "five springs". The number that matters is how many distinct resistance levels you can build.
For teaching, this decides whether you can place a client correctly or have to compromise. For a home practice, it decides how long before the machine stops offering an appropriate progression.
| Spec says | What to check | Why |
|---|---|---|
| "5 springs" | How many distinct tensions | Five identical springs give few useful combinations |
| "Color coded" | The manufacturer’s own key | No cross-brand standard exists |
| "Adjustable resistance" | Number of gradations | Marketing phrase with no fixed meaning |
| Spring rate in lb/in | Published or not | The only genuinely comparable figure |
Springs assist as often as they resist
On footwork the spring opposes you. On a supine roll-up with the carriage anchored, the same spring supports the movement. This dual role is why "more springs is harder" is wrong roughly half the time.
When a teacher adds a spring for a beginner, they are usually making the exercise easier, not harder — a point worth understanding before you self-program at home.
Reading a settings chart
Because color codes are brand-specific, a settings chart is only meaningful alongside the manufacturer’s own key. What is portable between machines is the spring rate in pounds per inch, and where a manufacturer publishes it you can compare directly across brands.
When moving between studios, the practical approach is to learn each machine’s system rather than trying to translate. Two red springs on one reformer may be substantially heavier or lighter than two red springs on another.
Typical settings by exercise
These are starting points rather than prescriptions — the right setting depends on the person, and on whether the spring is assisting or resisting in that particular exercise.
| Exercise | Typical springs | Spring role |
|---|---|---|
| Footwork | 3–4 | Resists |
| Bridging on the footbar | 2–3 | Resists |
| Leg circles in straps | 1 | Resists and assists |
| Short spine | 2 | Assists |
| Knee stretches | 2 | Resists |
| Long stretch | 2 | Resists |
| Seated arm pulls | 1 | Resists |
| Jumpboard | 3 | Resists and rebounds |
How springs fail, and what it feels like first
Fatigue is gradual and easy to miss. A spring that has permanently stretched sits longer at rest and delivers less resistance than the chart says, so the whole settings system quietly drifts. The first sign is usually a sense that an exercise has become easier without your having got stronger.
Corrosion is the other failure mode, and it matters more because it is a safety issue rather than a calibration one. Surface rust changes fatigue behavior, and a spring failing under load on a carriage a client is pushing against is a genuine incident.
Frequently asked questions
- How many springs should a reformer have?
- Four or five is standard. What matters more is how many distinct tension grades those springs represent — five springs in four grades is far more useful than five identical ones.
- Do heavier springs mean a harder workout?
- Not always. Where the spring assists the movement — many supine and roll-up exercises — a heavier spring makes it easier.
- How often should reformer springs be replaced?
- In studio use, every three to five years. Compare unloaded free length against the manufacturer spec; a spring that sits long has fatigued.
- Can I use springs from another manufacturer?
- Only if rate, free length and end fitting all match. Free length in particular changes resistance at the carriage home position, which is where most exercises begin.
- Why does the same setting feel different on another machine?
- Color codes are brand-specific, spring rates differ, and gear bar position changes the pre-stretch at the home position. Learn each machine rather than translating between them.