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

Exercise guide

Knee Drive

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

The Knee Drive is a dynamic bodyweight exercise that builds core stability and hip flexor strength while improving balance. It targets the lower abs and obliques through explosive hip flexion and controlled stabilization.

Reviewed by the Crucible Fit team · Updated June 2026

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

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Glutes

Equipment

  • Body weight

Setup

  1. Stand tall with feet hip-width apart and a slight bend in your knees.
  2. Engage your core and shift your weight slightly onto your standing leg.
  3. Position your arms in a 'runner's stance' with elbows bent at 90 degrees.

How to do it

  1. Drive your active knee upward toward your chest explosively while exhaling.
  2. Simultaneously swing the opposite arm forward to maintain balance and momentum.
  3. Lower the foot back to the starting position with control while inhaling.
  4. Switch legs and repeat the movement in an alternating fashion.

Form checklist

  • Keep your torso upright and avoid leaning backward as the knee rises.
  • Drive the knee straight up toward the chest, not out to the side.
  • Keep the standing leg stable with a soft knee to absorb impact.
  • Maintain a tight core throughout the movement to protect the lower back.

Pro tips

  • Imagine pulling your belly button toward your spine as the knee rises to maximize lower abdominal engagement.
  • Focus on a quick, powerful 'drive' phase followed by a slow, controlled descent to increase time under tension.

Make it harder

  • Incorporate a small hop on the standing leg at the peak of the drive to increase power and heart rate.
  • Hold a medicine ball or light weight at chest height to increase the demand on the core and shoulders.

Frequently asked

What muscles does the knee drive work?
The knee drive primarily targets the abs and obliques, and also works the glutes as secondary muscles.
What equipment do you need for the knee drive?
The knee drive requires no equipment — just your body weight.
Is the knee drive good for beginners?
Yes. The 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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