Supine Arm Series: Steps, Muscles and Common Mistakes

How to do the Supine Arm Series

Lie on your back on the Reformer carriage in a neutral spine, holding the strap handles in your hands with your legs resting in a tabletop position.

1. Reach your arms straight up toward the ceiling with your palms facing the footbar.
2. Press your arms down toward the carriage until your hands rest right beside your hips.
3. Hold this position for a brief moment while maintaining a steady neutral spine.
4. Open your arms out to the sides in a wide arc.
5. Circle your arms back up to the starting position above your chest.
6. Reverse the direction by opening your arms wide first and then pressing them down to your hips.
7. Return your hands straight up to the ceiling to complete the sequence.

• Breath. Teachers cue breathing differently, but a common pattern is to exhale as you press the straps down and inhale as you circle your arms back up.
• Where you feel it. You should feel the work in the muscles of your chest, back, and the back of your upper arms, along with a deep engagement in your abdomen. You should not feel pinching in your shoulders or strain in your lower back.
• How many. 5 to 8 slow repetitions in each direction

Common mistakes

• Losing neutral spine. Focus on keeping your transversus abdominis engaged so your lower back does not arch away from the carriage.
• Bending the wrists. Keep your wrists long and straight as you pull the straps, rather than curling your hands inward.
• Shrugging the shoulders. Keep your shoulders relaxed and resting heavy on the carriage as your arms move.
• Rushing the circles. Move at a slow, controlled pace to ensure your muscles do the work instead of momentum.

Make it easier or harder

Easier

• Keep your feet resting flat on the footbar instead of holding them in the air.
• Use a lighter spring tension to reduce the resistance on your arms.
• Make your arm circles smaller to maintain better control of your torso.

Harder

• Extend your legs straight out at a low angle while you move your arms.
• Use a slightly heavier spring tension to challenge your upper body muscles.

Who should be careful

• After the first trimester of pregnancy, many guidelines advise against long periods lying flat on the back. A side-lying or propped version is an alternative.
• Reformer springs and the moving carriage add load and instability. Learn it with a qualified instructor, who can set the springs for your body and goals.

Related exercises

• Chest Expansion Beginner to intermediate
• Down Stretch Intermediate
• Pilates Push-Up Intermediate to advanced
• Coordination Intermediate
• Kneeling Arm Series Beginner to intermediate

When to see a doctor or physical therapist

• Sharp or shooting pain in your shoulder joints.
• Numbness or tingling traveling down your arms or into your hands.
• Sudden, localized pain in your lower back.

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 reformer 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.