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  1. Home
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  3. Exercises
  4. /
  5. Core & Abs
  6. /
  7. L Sit

Exercise guide

L Sit

  • Advanced
  • Compound
  • Timed hold
  • Upper legs
  • Waist

The L-sit is a premier isometric core exercise that builds exceptional abdominal strength, hip flexor endurance, and scapular stability. It challenges the upper body to maintain a rigid frame while the core and quads work to hold the weight of the legs against gravity.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the L Sit demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Deltoids
  • Obliques

Secondary

  • Glutes
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Position yourself between the bars of a dip station with your hands firmly gripping the handles.
  2. Depress your shoulders downward, pushing your body up so your neck is long and shoulders are away from your ears.
  3. Lock your elbows completely and engage your triceps to create a stable base.

How to do it

  1. Inhale to create core tension, then exhale as you slowly lift your legs straight out in front of you.
  2. Raise your legs until they are parallel to the floor, forming a 90-degree 'L' shape with your torso.
  3. Hold the position while maintaining shallow, controlled breaths and keeping the legs perfectly straight.
  4. Lower your legs with control back to the starting position once the hold duration is complete.

Form checklist

  • Keep elbows fully locked out throughout the entire hold.
  • Maintain active shoulder depression; do not let your ears sink toward your shoulders.
  • Keep your knees locked and toes pointed to engage the entire lower body.
  • Ensure your hips stay tucked between or slightly in front of your hands.

Pro tips

  • Focus on 'pushing the bars into the ground' to maximize serratus anterior activation and lift height.
  • Squeeze your quadriceps as hard as possible; this creates reciprocal inhibition that helps the hip flexors maintain the hold.
  • Lean slightly forward into the hold to better engage the deep abdominal wall.

Make it harder

  • Transition into a V-Sit by lifting your feet above hip level toward your face.
  • Perform the movement on floor parallettes or the ground to increase the requirement for shoulder depression.

Frequently asked

What muscles does the l sit work?
The l sit primarily targets the abs, deltoids, and obliques, and also works the glutes and hip flexors as secondary muscles.
What equipment do you need for the l sit?
The l sit requires no equipment — just your body weight.
Is the l sit good for beginners?
The l sit is rated advanced. 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
  • Alternate Single Leg Raise PlankIntermediate · abs, deltoids, hamstrings, and obliques
  • Barbell Sitted Alternate Leg RaiseAdvanced · abs, deltoids, and obliques
  • Bear Crawl Low HipIntermediate · abs, deltoids, 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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