Pilates
Reformer Short Box Mermaid
The Reformer Short Box Mermaid is a seated side bend on a moving carriage. It trains controlled movement through your waist while challenging trunk stability.
- Intermediate
- Compound
- Moderate injury risk
- Rest 45 sec
How to do it
- Sit sideways on the short box with your knees bent and your feet supported on the carriage.
- Place the hand nearest the footbar on it, with your elbow slightly bent.
- Reach your free arm overhead.
- Press the carriage a short distance outward through your supporting hand.
- Bend sideways toward the footbar, reaching your raised arm over your head.
- Return your torso upright, allowing the carriage to glide home under control.
- Lower your raised arm to your side.
Form cues
- Keep both sitting bones heavy.
- Lengthen both sides of your waist.
- Exhale into the side bend.
Common mistakes
- Shrugging the supporting shoulderKeep space between your shoulder and ear as you press into the footbar.
- Turning the stretch into a twistKeep your chest facing forward rather than rotating toward the carriage.
- Collapsing over the footbarShorten the bend so your trunk stays supported rather than hanging from your arm.
Safety
Sitting on a raised box over a moving carriage creates a slip or fall risk if the box shifts or the springs pull you back abruptly. Forcing the bend can strain your back or supporting shoulder.
- Check that the footbar is locked and the box is positioned securely across the carriage.
- Use a spring setting appropriate for seated mermaid work; test a small carriage movement before reaching overhead.
- Keep the return slow enough that the carriage does not strike the stopper.
- End the set if you lose balance or cannot control the carriage.
Choose a floor-based version or get guidance from a physiotherapist first if back, hip, or shoulder pain prevents a comfortable seated side bend.
Muscles worked
Primary muscles
Secondary muscles
Equipment
- Pilates Reformer
- Pilates Sitting Box
Sets and reps
- Sets
- 1–2
- Target
- 6–8 reps per side
- Rest
- 45 sec
Start with a small range that you can repeat smoothly on both sides.