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  1. Home
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  3. Exercises
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  5. Core & Abs
  6. /
  7. Double Knee Drive

Exercise guide

Double Knee Drive

  • Beginner
  • Compound
  • Timed hold
  • Lower legs
  • Waist

The Double Knee Drive is a dynamic standing core exercise that builds hip flexor strength and abdominal definition while improving balance. It utilizes a repetitive 'standing crunch' motion to target the lower abs and obliques through explosive, unilateral movements.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Double Knee Drive demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Adductors
  • Glutes
  • Hamstrings

Equipment

  • Body weight

Setup

  1. Stand tall with your feet hip-width apart and your core tightly engaged.
  2. Raise both arms diagonally overhead or hold them at chest height with your elbows bent.
  3. Shift your weight slightly onto your left leg, keeping a soft bend in the knee to maintain stability.

How to do it

  1. Drive your right knee up toward your chest while simultaneously pulling your hands down toward your knee, exhaling sharply on the effort.
  2. Briefly tap your right toe back to the floor and immediately drive the same knee up a second time for the 'double' rep.
  3. Step back to the starting position and repeat the two-pulse sequence on the left leg.
  4. Continue alternating sides, maintaining a brisk and rhythmic tempo while inhaling as you reset between drives.

Form checklist

  • Keep your chest lifted and avoid rounding your upper back as you pull your arms down.
  • Focus on pulling your ribs toward your pelvis to engage the abdominals during the drive.
  • Maintain a slight bend in the standing leg to protect the joint and improve balance.
  • Land softly on the ball of your foot between reps to minimize impact.

Pro tips

  • Visualize a 'standing crunch'—the power should come from your core pulling the knee up, not just the hip flexor.
  • Squeeze the glute of your standing leg throughout the movement to create a rock-solid base of support.

Make it harder

  • Add a small hop on the standing leg during each knee drive to increase the plyometric intensity and heart rate.
  • Hold a light medicine ball or dumbbell to increase the resistance on the core and shoulders during the pull-down phase.

Frequently asked

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

Related exercises

  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals
  • 90 To 90Beginner · abs, glutes, obliques, and quadriceps
  • 90 To 90 SwitchIntermediate · abs, glutes, obliques, and quadriceps
  • Air BikeIntermediate · abs 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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