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  7. Lying Legs Triangle Drop

Exercise guide

Lying Legs Triangle Drop

  • Intermediate
  • Isolation
  • Rep-based
  • Waist

The Lying Legs Triangle Drop is a dynamic core exercise that targets the lower abdominals and obliques by moving the legs in a controlled triangular path, enhancing rotational stability and hip flexor strength.

Reviewed by the Crucible team · Updated June 2026

Watch the Lying Legs Triangle Drop demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Glutes

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your arms extended by your sides or tucked slightly under your glutes for lower back support.
  2. Extend your legs straight up toward the ceiling, pressing your lower back firmly into the floor.
  3. Engage your core and point your toes to create tension throughout the lower body.

How to do it

  1. Inhale as you lower your straight legs diagonally toward the floor on one side, stopping just before your lower back lifts.
  2. Sweep your legs horizontally across the bottom, keeping them 2-3 inches above the floor, until they reach the opposite side.
  3. Exhale as you pull your legs back up to the starting vertical position to complete the triangle shape.
  4. Alternate the direction of the triangle for each repetition to ensure balanced engagement.

Form checklist

  • Keep your lower back pressed into the mat at all times to protect the spine.
  • Maintain straight legs to maximize the lever length and abdominal tension.
  • Move with control; avoid using momentum to swing the legs through the pattern.
  • Keep your head and neck relaxed on the floor unless performing an advanced variation.

Pro tips

  • Focus on 'pulling' with your obliques as you sweep the legs across the bottom and back up to center.
  • Slow down the tempo during the horizontal sweep to significantly increase time under tension for the lower abs.

Make it harder

  • Hold a light dumbbell or medicine ball between your feet to increase resistance.
  • Lift your head and shoulder blades slightly off the floor to maintain constant tension in the upper abdominals.

Frequently asked

What muscles does the lying legs triangle drop work?
The lying legs triangle drop primarily targets the abs and obliques, and also works the glutes as secondary muscles.
What equipment do you need for the lying legs triangle drop?
The lying legs triangle drop requires no equipment — just your body weight.
Is the lying legs triangle drop good for beginners?
The lying legs triangle drop is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • 3/4 Sit-UpBeginner · abs and obliques
  • 45 Degree Bicycle Twisting CrunchIntermediate · abs and obliques
  • 45 Degree Lean Back Alternate Knee RaiseBeginner · abs and obliques
  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals

Train this with a plan, not guesswork

Crucible builds the lying legs triangle drop into a precise program around your body, equipment, location, and time.

Download on the App Store