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  7. Alternate Leg Raise

Exercise guide

Alternate Leg Raise

  • Beginner
  • Isolation
  • Rep-based
  • Lower legs
  • Upper legs
  • Waist

The Alternate Leg Raise is a foundational core exercise that isolates the lower abdominals and hip flexors by moving one limb at a time to maintain pelvic stability. It is highly effective for building the deep core strength required to protect the lower back during more complex movements.

Reviewed by the Crucible team · Updated June 2026

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

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Erector spinae
  • Glutes

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your legs fully extended and feet together.
  2. Place your arms by your sides with palms facing down, or tuck your hands under your glutes for additional lower back support.
  3. Engage your core by pulling your belly button toward your spine and pressing your lower back firmly into the floor.

How to do it

  1. Exhale as you lift one leg toward the ceiling, keeping it as straight as possible, until it is roughly perpendicular to the floor.
  2. Inhale as you slowly lower the leg back down to the starting position with a controlled 2-second tempo.
  3. Immediately repeat the movement with the opposite leg, alternating sides for each repetition.
  4. Ensure the non-moving leg remains stationary and pressed into the floor (or hovering slightly for more challenge).

Form checklist

  • Keep your lower back in constant contact with the floor; do not let it arch.
  • Maintain a slight micro-bend in the knees if you have tight hamstrings, but keep the movement at the hip.
  • Keep your neck and shoulders relaxed on the mat to avoid unnecessary tension.
  • Control the descent of the leg rather than letting it drop quickly.

Pro tips

  • Focus on the mind-muscle connection by imagining your lower abs pulling your thigh upward rather than just swinging your leg.
  • Point your toes to create full-body tension, which helps stabilize the pelvis during the unilateral movement.

Make it harder

  • Keep both heels hovering 2-3 inches off the floor throughout the entire set instead of resting them between reps.
  • Slow the eccentric (lowering) phase to 4 seconds to increase time under tension for the rectus abdominis.

Frequently asked

What muscles does the alternate leg raise work?
The alternate leg raise primarily targets the abs and obliques, and also works the erector spinae and glutes as secondary muscles.
What equipment do you need for the alternate leg raise?
The alternate leg raise requires no equipment — just your body weight.
Is the alternate leg raise good for beginners?
Yes. The alternate leg raise 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 this with a plan, not guesswork

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

Download on the App Store