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  1. Home
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  3. Exercises
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  5. Core & Abs
  6. /
  7. Alternate Leg Raise With Head-Up

Exercise guide

Alternate Leg Raise With Head-Up

  • Beginner
  • Isolation
  • Rep-based
  • Waist

This exercise targets the lower abdominals and hip flexors while maintaining constant tension on the upper core by keeping the head and shoulders elevated. It is highly effective for building core stability and improving control of the pelvic tilt.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Alternate Leg Raise With Head-Up demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs

Secondary

  • Obliques

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your legs fully extended.
  2. Lift your head and shoulders slightly off the floor, tucking your chin to engage the upper abdominals.
  3. Place your hands flat by your sides or tucked slightly under your glutes for lower back support.

How to do it

  1. Exhale and lift one leg toward the ceiling, keeping it straight, until it reaches a 70-90 degree angle.
  2. Inhale as you lower the leg back down with control, stopping just before your heel touches the floor.
  3. Immediately repeat the movement with the opposite leg, alternating sides in a rhythmic fashion.
  4. Maintain a slow, controlled tempo (2 seconds up, 2 seconds down) to maximize time under tension.

Form checklist

  • Keep your lower back pressed firmly into the mat at all times.
  • Ensure the non-moving leg stays hovering or pinned to the floor without arching the back.
  • Keep your chin tucked and shoulders lifted to maintain upper abdominal engagement.
  • Keep your knees locked to fully engage the quadriceps and hip flexors.

Pro tips

  • Focus on the mind-muscle connection by imagining your lower abs pulling your leg up rather than just swinging the limb.
  • Point your toes to create full-body tension and prevent the leg from bending.

Make it harder

  • Keep both feet hovering 3 inches off the ground throughout the entire set to eliminate the rest phase.
  • Slow down the eccentric (lowering) phase to 4 seconds to increase the challenge to the lower abs.

Frequently asked

What muscles does the alternate leg raise with head-up work?
The alternate leg raise with head-up primarily targets the abs, and also works the obliques as secondary muscles.
What equipment do you need for the alternate leg raise with head-up?
The alternate leg raise with head-up requires no equipment — just your body weight.
Is the alternate leg raise with head-up good for beginners?
Yes. The alternate leg raise with head-up is a beginner-friendly movement and a strong foundation to build on.

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 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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