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  7. Knee Raise Step Jack

Exercise guide

Knee Raise Step Jack

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

The Knee Raise Step Jack is a dynamic, low-impact cardio movement that targets the lower body and core while improving coordination and heart rate. By combining a step-up with a high knee drive and overhead arm reach, it effectively engages the quadriceps, deltoids, and abdominals.

Reviewed by the Crucible team · Updated June 2026

Watch the Knee Raise Step Jack demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Calves
  • Quadriceps

Secondary

  • Obliques
  • Serratus anterior

Equipment

  • Body weight

Setup

  1. Stand facing a stable step or platform with feet hip-width apart.
  2. Position yourself close enough to the step so your entire foot can land firmly on the surface.
  3. Keep your arms relaxed at your sides and maintain an upright posture with a tight core.

How to do it

  1. Step your right foot onto the center of the platform, pressing through the heel to elevate your body.
  2. As you stand up, drive your left knee toward your chest while simultaneously swinging both arms overhead in a wide arc.
  3. Exhale sharply as the knee reaches its peak to maximize abdominal engagement.
  4. Step back down with the left foot followed by the right, then repeat the sequence starting with the left foot.

Form checklist

  • Keep your chest up and shoulders back throughout the movement.
  • Ensure the stepping foot is fully on the platform to prevent slipping.
  • Avoid leaning backward when driving the knee upward.
  • Land softly on the floor to minimize impact on the joints.

Pro tips

  • Focus on the mind-muscle connection by consciously crunching your abs at the top of the knee drive.
  • Maintain a brisk, rhythmic tempo to keep your heart rate in the aerobic zone.

Make it harder

  • Increase the step height to deepen the range of motion for the quadriceps and glutes.
  • Hold light dumbbells to increase the demand on the deltoids and core stability.

Frequently asked

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

Related exercises

  • Air Punches MarchBeginner · calves, pectorals, and quadriceps
  • Band DeadliftBeginner · calves, glutes, hamstrings, quadriceps, and trapezius
  • Barbell Hang Clean Below The KneesAdvanced · calves, glutes, hamstrings, quadriceps, and trapezius
  • Barbell Mixed Grip DeadliftIntermediate · calves, glutes, hamstrings, quadriceps, and trapezius

Train this with a plan, not guesswork

Crucible builds the knee raise step jack into a precise program around your body, equipment, location, and time.

Download on the App Store