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Exercise guide

Sphinx

  • Beginner
  • Isolation
  • Timed hold
  • Back
  • Shoulders

The Sphinx is a foundational isometric hold that improves spinal mobility and strengthens the lower trapezius while providing a gentle stretch to the abdominal wall. It is highly effective for correcting rounded shoulders and improving postural awareness through scapular depression.

Reviewed by the Crucible team · Updated June 2026

Watch the Sphinx demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Erector spinae

Secondary

  • Obliques

Equipment

  • Body weight

Setup

  1. Lie face down on a mat with your legs extended straight behind you, hip-width apart.
  2. Place your forearms flat on the floor, parallel to each other, with your elbows positioned directly under your shoulders.
  3. Spread your fingers wide and press your palms and the tops of your feet firmly into the mat.

How to do it

  1. Inhale as you press through your forearms to lift your chest and head away from the floor, lengthening your spine.
  2. Actively pull your shoulder blades down and back, feeling the engagement in your trapezius and mid-back.
  3. Hold the position for 30-60 seconds, maintaining a steady, deep breathing pattern through the nose.
  4. Exhale as you slowly lower your chest back to the starting position with control.

Form checklist

  • Keep your neck long and gaze slightly forward to avoid crunching the back of the neck.
  • Maintain a firm press through the forearms to prevent 'sinking' into the shoulder joints.
  • Engage your glutes and core slightly to protect the lumbar spine from excessive pinching.
  • Ensure elbows stay stacked under the shoulders, not flared out to the sides.

Pro tips

  • Imagine pulling the floor toward your hips with your forearms to create more tension in the mid-back and open the chest further.
  • Focus on 'zipping up' your lower abdominals away from the mat to increase the stability of the pose.

Make it harder

  • Transition into a 'Seal' pose by straightening the arms and lifting the elbows, provided you have the spinal mobility.
  • Incorporate neck carousels by slowly rotating the head while maintaining the lifted chest position to challenge trap stability.

Frequently asked

What muscles does the sphinx work?
The sphinx primarily targets the erector spinae, and also works the obliques as secondary muscles.
What equipment do you need for the sphinx?
The sphinx requires no equipment — just your body weight.
Is the sphinx good for beginners?
Yes. The sphinx is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • Alternating SupermanBeginner · erector spinae, glutes, and hamstrings
  • Around The World SupermanIntermediate · erector spinae, glutes, hamstrings, and lats
  • Around The World Superman HoldIntermediate · erector spinae, glutes, hamstrings, lats, and trapezius
  • Back Bend Over Bench StretchIntermediate · erector spinae

Train this with a plan, not guesswork

Crucible builds the sphinx into a precise program around your body, equipment, location, and time.

Download on the App Store