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  7. Knee Raise

Exercise guide

Knee Raise

  • Intermediate
  • Compound
  • Timed hold
  • Waist

The standing knee raise targets the lower abdominals and hip flexors while improving unilateral balance and stability through the glutes and quadriceps of the standing leg. It is an effective functional movement for core activation and hip mobility.

Reviewed by the Crucible team · Updated June 2026

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

Muscles worked

Primary

  • Abs

Secondary

  • Hip flexors

Equipment

  • Body weight

Setup

  1. Stand tall with your feet hip-width apart and your arms at your sides or hands on your hips.
  2. Engage your core by pulling your navel toward your spine and maintain a neutral pelvis.
  3. Distribute your weight evenly across both feet to establish a stable base.

How to do it

  1. Exhale as you lift your right knee toward your chest until your thigh is at least parallel to the floor.
  2. Hold the peak contraction for a split second while keeping your torso upright and your standing leg strong.
  3. Inhale as you slowly lower your foot back to the starting position with controlled tempo.
  4. Repeat the movement with your left leg, alternating sides for the duration of the set.

Form checklist

  • Keep your chest lifted and avoid leaning backward as the knee rises.
  • Drive the heel of your standing foot into the ground to engage the glute for stability.
  • Ensure your hips remain level and do not tilt or 'hike' to one side.
  • Move with control rather than using momentum to swing the leg up.

Pro tips

  • Focus on 'crunching' your lower abs to pull the knee up rather than just using your hip flexors.
  • Maintain a slight, soft bend in the standing knee to protect the joint and increase muscle engagement.

Make it harder

  • Pause at the top of the movement for 3 seconds to challenge your balance and core endurance.
  • Perform the movement with your arms extended directly overhead to increase the demand on your core stabilizers.

Frequently asked

What muscles does the knee raise work?
The knee raise primarily targets the abs, and also works the hip flexors as secondary muscles.
What equipment do you need for the knee raise?
The knee raise requires no equipment — just your body weight.
Is the knee raise good for beginners?
The knee raise is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • 3/4 Sit-UpBeginner · abs and obliques
  • 45 Degree Bicycle Twisting CrunchIntermediate · abs and obliques
  • 45 Degree Lean Back Alternate Knee RaiseBeginner · abs and obliques
  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals

Train this with a plan, not guesswork

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

Download on the App Store