Twist Crunch (Legs Up)

Twist Crunch (Legs Up) Exercise Description

The Twist Crunch (Legs Up) is a bodyweight abdominal exercise that combines spinal flexion with controlled trunk rotation. Performed supine with the hips and knees flexed to about 90 degrees (shins parallel to the floor), it emphasizes the rectus abdominis while strongly engaging the external and internal obliques. Keeping the pelvis stable and the lower back gently in contact with the floor helps maintain alignment and reduces unwanted motion through the hips. The movement is small and precise: you lift the shoulder blades off the floor and rotate the rib cage toward the opposite thigh—shoulders move, not the elbows. This legs-up position encourages abdominal bracing, limits momentum, and focuses the effort on the torso rather than the legs.

Muscle Groups: Abs, Core, Waist
Target Muscles: Rectus Abdominis
Assisting Muscles: External Obliques, Internal Obliques
Stabilizing Muscles: Iliacus, Multifidus, Psoas Major, Transversus Abdominis
Body Area: Upper Body
Body Parts: Core, Torso
Body Surface: Front
Body Symmetry: Unilateral
Equipment: Bodyweight
Exercise Patterns: Other
Exercise Type: Strength
Functional Grouping: Trunk Flexors
Joint Involvement: Other
Muscle Location: Stomach
Movement Direction: Rotational
Muscle Position: Anterior
Gender: Male

How To Do The Twist Crunch (Legs Up) Exercise

‘- Lie on your back; bring hips and knees to 90°, shins parallel, feet relaxed.
– Lightly support your head with fingertips at your temples or behind ears; keep elbows wide.
– Set ribs down and posteriorly tilt the pelvis so the low back gently contacts the floor.
– Maintain a neutral neck with a soft chin tuck; eyes toward the ceiling.
– Inhale to prepare; brace the abdomen as if exhaling through a straw.
– Exhale as you curl the head and shoulder blades off the floor and rotate the rib cage to bring one shoulder toward the opposite knee.
– Keep elbows wide; avoid pulling on the head or leading with the elbows.
– Pause briefly at the top; keep the pelvis steady and legs quiet—no swinging.
– Inhale as you de-rotate and lower the shoulder blades to the floor under control.
– Repeat, rotating to the other side on the next repetition.
– Avoid: arching the lower back, jutting the chin, rushing the motion, or holding your breath.

Twist Crunch (Legs Up) Tips

‘- Start with hips and knees at about 90° and shins parallel to the floor, keeping the feet relaxed.
– Lightly support your head with fingertips at your temples or behind your ears and keep the elbows wide.
– Set the ribs down and posteriorly tilt the pelvis so the lower back gently contacts the floor before you move.
– Maintain a neutral neck with a soft chin tuck and keep your eyes toward the ceiling.
– Inhale to prepare, then brace the abdomen as if you were exhaling through a straw before starting the rep.
– As you exhale, curl the head and shoulder blades off the floor and rotate the rib cage to bring one shoulder toward the opposite knee.
– Focus on moving the shoulders, not the elbows, and avoid pulling on the head as you twist.
– Pause briefly at the top of the movement while keeping the pelvis steady and the legs quiet with no swinging.
– Inhale as you de-rotate and lower the shoulder blades back to the floor under control.
– Avoid arching the lower back at any point in the movement.
– Avoid jutting the chin forward as you curl and rotate.
– Use a controlled tempo instead of rushing through the motion.
– Keep breathing throughout the set rather than holding your breath.

Twist Crunch (Legs Up) Beginner Introduction

The Twist Crunch (Legs Up) is a bodyweight core move done on the floor with the legs lifted and bent in the air. It blends a small curl of the upper body with a gentle turn through the torso, placing strong emphasis on the abs and side abs. With the thighs and lower legs raised, the lower body contributes less, encouraging the mid-section to handle most of the work instead of the hips or legs.

This exercise highlights control, stability, and precise movement rather than large, sweeping motions. Only the upper back comes away from the floor as the chest turns toward the opposite thigh, while the lower back stays lightly connected to the ground. The twist comes from the ribcage and shoulders rather than from swinging the elbows or legs, which helps concentrate tension through the front and sides of the waist. Steady, deliberate breathing typically accompanies each repetition, reinforcing strong bracing through the core as the trunk curls and rotates, then returns smoothly to the starting position.