Pilates Mermaid: Steps, Muscles and Common Mistakes

How to do the Mermaid

Sit on your mat with your legs folded to one side, resting your weight on your sitting bones as evenly as possible.

1. Reach the arm furthest from your feet straight up toward the ceiling.
2. Keep your opposite hand resting lightly on your mat or your shin for support.
3. Bend your spine sideways over your legs, reaching your raised arm in a long arc.
4. Keep both sitting bones anchored to the mat as you stretch.
5. Pause briefly to feel the opening along the side of your ribcage.
6. Use your core to pull your torso back upright to the starting position.
7. Lower your arm down to complete the movement before repeating.

• Breath. Teachers cue breathing differently, but you will often inhale as you reach up and over, and exhale as you return to the start. Some instructors prefer the opposite, so find the rhythm that helps you maintain a steady pace.
• Where you feel it. You should feel a deep stretch along the side of your ribs, waist, and back, with gentle effort in your obliques. You should not feel pinching in your lower back or strain in your neck.
• How many. 3 to 5 slow repetitions on each side

Common mistakes

• Lifting the hip. Keep both sitting bones firmly planted on the mat to ensure the stretch happens in your torso rather than shifting your pelvis.
• Collapsing the chest. Keep your chest open and facing forward instead of twisting toward the floor.
• Crunching the neck. Leave space between your shoulder and your ear, letting your head follow the natural curve of your spine.
• Pushing too hard. Move gently into the side bend without forcing the range of motion, letting your muscles lengthen naturally.

Make it easier or harder

Easier

• Sit cross-legged if folding your legs to one side is uncomfortable for your knees or hips.
• Sit on a folded towel or small cushion to help level your pelvis.
• Make the side bending motion smaller and keep your reaching arm slightly bent.

Harder

• Add a gentle spinal rotation at the deepest point of the side bend before returning to the start.
• Perform the movement with both arms reaching overhead to challenge your obliques further.

Who should be careful

• Side bending under load may need to be limited with osteoporosis or a recent back injury.

Related exercises

• Mermaid on the Reformer Beginner
• Bent Knee Fall Out Beginner
• Open Book Beginner
• Spine Twist Beginner
• Corkscrew Intermediate to advanced

This exercise is part of our pages on Pilates for Scoliosis, Pilates During Pregnancy, Pilates for Neck Pain, Pilates for Golfers, Pilates for Flexibility.

When to see a doctor or physical therapist

• Sharp or shooting pain in your lower back during the side bend.
• Pinching sensations in your hip joints or knees while sitting in the folded position.
• Numbness or tingling radiating down your arm or side.
• Sudden dizziness or lightheadedness when changing positions.

This page is general education, not a diagnosis or treatment plan. If you have a health condition, are pregnant or are recovering from an injury or surgery, check with your own clinician before trying new exercises.

How we put this page together. Exercise data (type, level, equipment and muscles) was compiled by our editors from the classical mat order in Joseph Pilates’ 1945 book and from commonly taught mat repertoire. Muscle lists are a general anatomy guide; cueing differs between teachers. Text drafted with AI assistance and checked by the Editorial Team. See our editorial policy. Last checked October 2026.