Flexion Leg Sit-Up

A sit-up variation where legs are held in a fixed flexed position. This isolates the upper abdominals and minimizes hip flexor involvement.

Exercise Details

Level: Beginner
Body Area: core
Type: core

Required Equipment

Bodyweight-only

Target Muscle Groups

Primary

Abs

Secondary

Quads

Setup

Lie on your back and lift your legs into a tabletop position (90-degree bend). Place hands behind your head or reach forward.

Instructions

1. Crunch and sit up toward your stationary legs.
2. Focus on curling the ribcage toward the pelvis.
3. Exhale at the top.
4. Lower back down slowly.
5. Keep the lower back grounded between reps.

Common Mistakes

1. Using leg momentum to sit up.
2. Pulling the neck.
3. Losing the 90-degree leg angle.

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