Side Splits: A Complete Guide
Quick Intro
Side Splits is a reformer Pilates exercise performed standing sideways on the reformer, one foot on the stationary platform and one on the moving carriage, pressing the carriage foot out to the side to widen the stance and drawing it back in. The stationary foot never moves, which means the exercise happens on a mixed surface: balance on one side, a spring-loaded press on the other.
Equipment Needed
A Pilates Reformer is required, with no substitute possible, since standing across the stationary platform and the moving carriage at once is the mechanism being trained. No further equipment is used.
Why It Matters
Widening the stance against spring resistance asks for inner-thigh flexibility, and standing across a stationary platform and a moving carriage at once takes leg endurance, balance and coordination. The inner thigh muscles (adductors) lengthen under control on the outward press and shorten to draw the legs together on the return, and a smaller glute muscle at the side of the hip (gluteus medius) helps control the hip as the legs split apart. The front of the thigh (quadriceps, rectus femoris) supports both legs through the stance. A band of connective tissue running down the outside of the thigh, along with its supporting hip muscle (IT band, TFL), stabilizes the standing leg, and a deep core muscle that wraps around the torso like a corset (transverse abdominis) keeps the torso upright and facing forward throughout.
When to Do It
Side Splits works well in the standing portion of a reformer session, usually placed among the other exercises performed balanced across the platform and carriage. Two to three sessions a week is a reasonable pace for building this standing balance-and-press control.
Anyone with a current hip, knee or ankle issue should get individual guidance before adding this exercise, since the standing leg bears sustained load while the carriage leg works against spring resistance.
Getting Ready
A few rounds of standing on the platform alone, without the carriage moving, preview the balance this exercise depends on. Pressing the carriage foot out just partway a few times checks how the stance feels before the full range is attempted.
Step-by-Step Instructions
1. The setup. Stand sideways on the reformer, one foot on the stationary platform, one foot on the carriage.
2. The press. Press the carriage foot out to the side, widening the stance.
3. The draw. Draw the carriage foot back in with control, resisting the spring the whole way.
4. The repeat. Continue pressing out and drawing in for the working set, keeping the pelvis level throughout.
How Many, How Often
Side Splits is dosed by reps, with each full press-out-and-return counting as one.
| Level | Where you’re at | What to do |
|---|---|---|
| Beginner | New to balancing across the platform and carriage | 2 sets of 5 to 6 reps per side, with a smaller press |
| Intermediate | The stance feels steady through a fuller press | 2 to 3 sets of 6 to 8 reps per side |
| Advanced | Comfortable with a full-range press under load | 3 sets of 8 to 10 reps per side |
The pelvis staying level and facing forward matters more here than how wide the stance opens, since hips that rotate open as the legs split is the clearest sign the pelvis has stopped controlling the movement.
Modifications and Variations
As an easier version, Side Splits — Lighter Spring reduces the spring tension, making the press easier to control while the standing balance is still being learned.
As a harder version, Side Splits — Single Leg Standing balances on the carriage leg without the stationary platform for support, removing the fixed base and asking that leg to manage the balance alone.
Common Mistakes to Avoid
Letting the hips rotate open as the legs split. Allowing the pelvis to turn or open toward the carriage side, without staying square to the front, breaks the side-to-side control this exercise depends on. The hips should stay level and facing forward through the entire range.
Letting the carriage snap back on the return. Allowing the spring to pull the leg back in unchecked wastes the control the legs are meant to build on the return. The return should feel just as deliberate as the press.
Leaning the torso to help balance rather than staying upright. Tipping the upper body toward the stationary side to compensate for a wobbly stance trades away the postural control this exercise is meant to train. Staying tall and centred, even if that means a smaller press, protects the balance benefit.
After Your Set
Standing and folding forward into a gentle straddle stretch, hands reaching toward the floor, releases the inner thighs after a set of repeated splits. A few slow ankle circles on the leg that worked the carriage ease out any tension the balancing left in the joint.
Going Deeper
This exercise tests balance across two different surfaces at once, since one foot stands on something fixed while the other manages a moving, spring-loaded carriage. As the stance widens, the hips tend to rotate open to make the reach feel easier, which takes the stretch off the inner thighs. Keeping the pelvis square at a narrower stance builds flexibility and control faster.
Someone new to this exercise generally manages a narrower, controlled split within a few sessions, then works toward a wider range over two to three weeks.
How to Know You’re Improving
- A pelvis that stays level and facing forward through the entire range
- A return that stays as controlled as the outward press
- A torso that stays upright and centred, without leaning to compensate
- A stance width that grows while the hips stay square
Hips that stay square during the split matter more than how wide the stance reaches.
Muscles Worked
- Adductors (the inner thigh muscles, lengthening under control on the way out and drawing the legs together on the return)
- Gluteus Medius (a smaller glute muscle at the side of the hip, controlling the hip as the legs split apart)
- Rectus Femoris (one of the quadriceps at the front of the thigh, supporting both legs as the stance widens and closes)
- IT Band and Tensor Fasciae Latae (a band of connective tissue down the outer thigh and the hip muscle that tensions it, stabilizing the standing leg)
- Transverse Abdominis (a deep core muscle that wraps around the torso like a corset, keeping the torso upright and facing forward)
FAQ
Why does one foot stay on a platform instead of both being on the carriage? The stationary platform gives one leg a fixed base while the other leg manages the moving carriage, which is what creates this exercise’s specific mix of standing balance and spring-loaded resistance.
Is it normal for one side to feel noticeably harder than the other? Yes, a difference in balance and control between the two sides is common, especially early on. Giving the weaker side equal training attention tends to even that difference out over time.
Is some inner-thigh or hip fatigue after this exercise normal? Yes, fatigue through the inner thighs and the outer hip after a full set on each side is expected. Sharp pain in the hip or knee calls for a different response: stop, ease off and check in with a doctor or physical therapist if it doesn’t settle.
Is a lighter spring a good idea if the standard load feels unstable? Yes, a lighter spring is a reasonable way to build the balance and the pattern before reaching for the full working load, and Side Splits — Lighter Spring is built that way.
How often should Side Splits be practiced? Two to three times a week, as part of the standing portion of a broader reformer session, suits most people building this balance and control.
Related to Side Splits — Lighter Spring as the easier version performed with reduced spring tension and Side Splits — Single Leg Standing as the harder version balanced on the carriage leg alone.