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  3. Exercises
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  5. Core & Abs
  6. /
  7. Figure 4 Spinal Rotation

Exercise guide

Figure 4 Spinal Rotation

  • Beginner
  • Compound
  • Rep-based
  • Lower legs
  • Upper legs
  • Waist

This dynamic mobility exercise combines a glute stretch with spinal rotation to improve hip flexibility and core rotational control. It effectively targets the obliques and gluteus medius while releasing tension in the lower back.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Figure 4 Spinal Rotation demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Glutes
  • Obliques

Secondary

  • Abs
  • Hip flexors
  • Quadriceps

Equipment

  • Body weight

Setup

  1. Lie flat on your back with your knees bent and feet flat on the floor, hip-width apart.
  2. Cross your right ankle over your left knee, creating a '4' shape with your legs.
  3. Extend your arms out to the sides in a 'T' position with your palms facing down for stability.

How to do it

  1. Exhale as you slowly rotate your hips to the left, lowering the sole of your right foot and the side of your left knee toward the floor.
  2. Keep both shoulders pinned firmly to the ground throughout the rotation.
  3. Inhale as you engage your obliques to pull your legs back to the center starting position with control.
  4. Perform the desired number of repetitions on one side before switching leg positions.

Form checklist

  • Keep both shoulder blades in contact with the floor at all times.
  • Maintain the '4' shape by keeping the crossed ankle flexed and the knee pushed outward.
  • Move slowly and avoid using momentum to swing the legs.
  • Ensure the movement comes from the waist and hips, not the upper back.

Pro tips

  • Actively push your crossed knee away from your torso during the rotation to maximize the stretch in the outer glute.
  • Focus on using your abdominal muscles to 'pull' your lower body back to the start rather than pushing off the floor.

Make it harder

  • Hover the bottom foot an inch off the ground throughout the set to increase core stability demands.
  • Add a 5-second isometric hold at the bottom of the rotation to deepen the stretch and increase time under tension.

Frequently asked

What muscles does the figure 4 spinal rotation work?
The figure 4 spinal rotation primarily targets the glutes and obliques, and also works the abs, hip flexors, and quadriceps as secondary muscles.
What equipment do you need for the figure 4 spinal rotation?
The figure 4 spinal rotation requires no equipment — just your body weight.
Is the figure 4 spinal rotation good for beginners?
Yes. The figure 4 spinal rotation is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • 90 To 90Beginner · abs, glutes, obliques, and quadriceps
  • 90 To 90 SwitchIntermediate · abs, glutes, obliques, and quadriceps
  • Ardha Matsyendrasana Yoga PoseIntermediate · abs, glutes, obliques, and trapezius
  • Back Leg Lift JackBeginner · abs, glutes, hamstrings, and obliques

Train it with Crucible Fit.

Every movement in this library is in the app with video and instructions, ready for your own sessions on the days between Crucibles. Your first Crucible is on us.

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