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  3. Exercises
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  5. Core & Abs
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  7. Seated Alternate In Out Leg Raise Over Bench

Exercise guide

Seated Alternate In Out Leg Raise Over Bench

  • Intermediate
  • Compound
  • Rep-based
  • Upper legs
  • Waist

This intermediate core exercise isolates the lower abdominals and hip flexors through a lateral "rainbow" motion over a bench. It challenges trunk stability and oblique control by requiring alternating unilateral leg movement while maintaining a seated V-position.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Seated Alternate In Out Leg Raise Over Bench demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Hamstrings

Equipment

  • Body weight

Setup

  1. Sit at the end of a flat bench with your legs extended and hands gripping the sides of the bench behind your hips for balance.
  2. Lean your torso back slightly to create a V-shape with your body and lift your feet 2-3 inches off the floor.
  3. Position yourself so your legs are centered with the length of the bench.

How to do it

  1. Exhale as you lift one leg up and over the side of the bench in a controlled arc, then immediately bring it back to the center.
  2. Inhale as you stabilize, then repeat the out-and-in movement with the opposite leg.
  3. Maintain a steady, rhythmic tempo, ensuring neither foot touches the ground or the bench during the set.

Form checklist

  • Keep your chest lifted and avoid shrugging your shoulders toward your ears.
  • Engage your quads to keep your legs as straight as possible throughout the movement.
  • Minimize torso rotation; only your legs should move laterally while the spine stays neutral.
  • Keep your lower back supported by bracing your core, avoiding any excessive rounding.

Pro tips

  • Imagine there is a tall hurdle on the side of the bench to force a higher leg lift, maximizing lower ab recruitment.
  • Point your toes away from you to increase the lever length and tension on the hip flexors and quads.

Make it harder

  • Perform the movement with your hands off the bench and arms extended forward to remove upper body stability.
  • Wear ankle weights to increase the resistance on the hip flexors and abdominals.

Frequently asked

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

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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