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  3. Exercises
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  5. Legs
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  7. Standing Bent Knee Figure 8

Exercise guide

Standing Bent Knee Figure 8

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

This dynamic mobility exercise enhances hip joint health and core stability by moving the femur through a full range of rotation. It effectively engages the hip flexors and adductors while forcing the standing leg's glutes and core to stabilize the body.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Standing Bent Knee Figure 8 demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Adductors
  • Glutes
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Stand tall with feet hip-width apart and engage your core.
  2. Shift your weight onto your standing leg, maintaining a soft bend in the knee.
  3. Lift the opposite knee until the thigh is roughly parallel to the floor with the foot flexed.

How to do it

  1. Lead with the lifted knee to draw a horizontal '8' (infinity symbol) in the air, moving the knee out to the side then across the midline.
  2. Exhale as you pull the knee across your body and inhale as you open the hip outward.
  3. Maintain a slow, controlled tempo, focusing on the fluidity of the hip rotation throughout the entire pattern.

Form checklist

  • Keep your pelvis level and avoid 'hiking' the hip of the moving leg.
  • Maintain an upright torso; do not lean to the side to compensate for range of motion.
  • Keep the standing foot rooted firmly into the ground with weight distributed evenly.
  • Ensure the movement is coming from the hip joint rather than just swinging the lower leg.

Pro tips

  • Focus on the mind-muscle connection with your deep hip rotators and adductors to ensure the movement is smooth and deliberate.
  • Keep the core braced as if preparing for a light impact to prevent the lower back from arching during the rotation.

Make it harder

  • Perform the exercise while standing on an unstable surface like a foam pad to further challenge proprioception.
  • Increase the size of the figure-8 to the maximum range of motion your hip allows without tilting your pelvis.

Frequently asked

What muscles does the standing bent knee figure 8 work?
The standing bent knee figure 8 primarily targets the abs, adductors, glutes, and hip flexors.
What equipment do you need for the standing bent knee figure 8?
The standing bent knee figure 8 requires no equipment — just your body weight.
Is the standing bent knee figure 8 good for beginners?
Yes. The standing bent knee figure 8 is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • Kneeling Forward Hip CirclesBeginner · abs, adductors, erector spinae, glutes, hip flexors, and obliques
  • Down To Upward DogIntermediate · abs, erector spinae, glutes, hip flexors, obliques, and quadriceps
  • Hip Circles StretchBeginner · adductors, glutes, hip flexors, and obliques
  • Medicine Ball Single Leg Balance ThrowAdvanced · abs, glutes, hip flexors, obliques, and quadriceps

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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