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  7. L Sit On Chair

Exercise guide

L Sit On Chair

  • Intermediate
  • Compound
  • Timed hold
  • Lower legs
  • Upper legs
  • Waist

The L-Sit on a chair is a demanding isometric hold that develops elite core compression strength, shoulder stability, and hip flexor endurance. It forces the triceps and deltoids to support the body weight while the abdominals and quadriceps work in unison to maintain a horizontal leg position.

Reviewed by the Crucible team · Updated June 2026

Watch the L Sit On Chair demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Deltoids
  • Obliques

Secondary

  • Erector spinae
  • Glutes
  • Hamstrings

Equipment

  • Body weight

Setup

  1. Place two sturdy, stable chairs side-by-side or use a single wide chair with hands on the edges.
  2. Sit on the edge of the seat with your palms flat next to your hips and fingers facing forward.
  3. Engage your core and pull your shoulder blades down and back to prepare for the lift.

How to do it

  1. Exhale and press firmly through your palms to lift your hips off the seat, locking your elbows completely.
  2. Extend your legs straight out in front of you until they are parallel to the floor, forming an 'L' shape with your body.
  3. Hold this position statically, maintaining a tall chest and shallow, controlled breathing.
  4. Lower your hips back to the seat with control once the set duration is complete.

Form checklist

  • Keep elbows fully locked out throughout the entire hold.
  • Actively depress your shoulders; do not let your ears sink toward your shoulders.
  • Keep your knees perfectly straight and toes pointed.
  • Maintain a 90-degree angle between your torso and your legs.

Pro tips

  • Think about 'pushing the chair away' to engage the serratus anterior and create more lift.
  • Squeeze your quads intensely to prevent your feet from sagging toward the floor.
  • Lean your torso slightly forward to help counterbalance the weight of your legs.

Make it harder

  • Lift your legs higher than parallel (V-Sit) to increase the demand on the lower abs and hip flexors.
  • Perform the movement on the floor to eliminate the extra clearance provided by the chair height.

Frequently asked

What muscles does the l sit on chair work?
The l sit on chair primarily targets the abs, deltoids, and obliques, and also works the erector spinae, glutes, and hamstrings as secondary muscles.
What equipment do you need for the l sit on chair?
The l sit on chair requires no equipment — just your body weight.
Is the l sit on chair good for beginners?
The l sit on chair 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
  • Alternate Single Leg Raise PlankIntermediate · abs, deltoids, hamstrings, and obliques
  • Bear Crawl Low HipIntermediate · abs, deltoids, and obliques
  • Bear Plank Floating Leg ExtensionIntermediate · abs, deltoids, hamstrings, and obliques

Train this with a plan, not guesswork

Crucible builds the l sit on chair into a precise program around your body, equipment, location, and time.

Download on the App Store