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  1. Home
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  3. Exercises
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  5. Core & Abs
  6. /
  7. Lying Floor Single Leg Negative Dragon Flag

Exercise guide

Lying Floor Single Leg Negative Dragon Flag

  • Advanced
  • Compound
  • Rep-based
  • Waist

This advanced core exercise focuses on the eccentric (lowering) phase to build extreme abdominal strength and anti-extension control. By using a single-leg tuck, you reduce the lever length to master the tension required for a full dragon flag while heavily engaging the lats and triceps for stability.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Lying Floor Single Leg Negative Dragon Flag demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Lats
  • Obliques

Secondary

  • Erector spinae

Equipment

  • Body weight

Setup

  1. Lie on your back on the floor with your head positioned against a sturdy anchor point, such as a wall, heavy rack, or weighted bench.
  2. Reach overhead and grip the anchor point firmly with both hands, keeping your elbows tucked in.
  3. Lift your hips and legs vertically until your weight is supported by your upper back and shoulders, ensuring no pressure is on your neck.
  4. Tuck one knee tightly toward your chest while keeping the other leg fully extended and pointing toward the ceiling.

How to do it

  1. Inhale deeply and brace your entire core, creating a rigid line from your shoulders to the foot of the extended leg.
  2. Exhale slowly as you lower your torso and the extended leg toward the floor in a controlled, 3-5 second negative phase.
  3. Maintain a straight line through your hips and the extended leg, preventing any hinging at the waist.
  4. Stop just before your lower back or glutes touch the floor, then drop your hips to reset and switch legs for the next rep.

Form checklist

  • Keep your weight on your shoulder blades and upper back, never on your neck.
  • Pull hard on the anchor point to engage your lats and triceps, which stabilizes the upper body.
  • Ensure the lower back does not arch; if it does, stop the descent and reset.
  • Keep the tucked knee pulled as close to the chest as possible to maintain control.

Pro tips

  • Think of 'pulling' the anchor point toward your head to create maximum full-body tension and lat engagement.
  • Squeeze the glute of the extended leg to help maintain a neutral pelvis and prevent lower back strain.

Make it harder

  • Increase the eccentric duration to 8-10 seconds per repetition.
  • Slowly move the tucked knee further away from your chest to increase the lever length and difficulty.

Frequently asked

What muscles does the lying floor single leg negative dragon flag work?
The lying floor single leg negative dragon flag primarily targets the abs, lats, and obliques, and also works the erector spinae as secondary muscles.
What equipment do you need for the lying floor single leg negative dragon flag?
The lying floor single leg negative dragon flag requires no equipment — just your body weight.
Is the lying floor single leg negative dragon flag good for beginners?
The lying floor single leg negative dragon flag is rated advanced. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Back Steps PlankIntermediate · abs, lats, and obliques
  • Band Standing Single Arm Twist RowIntermediate · abs, lats, obliques, and trapezius
  • Barbell Diagonal Leg Lift RolloutAdvanced · abs, hamstrings, lats, and obliques
  • Barbell Hip Twist RolloutIntermediate · abs, lats, 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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