Core · Bodyweight
Straight Legs Lying Crunch
How to do the straight legs lying crunch, the muscles it works, and the mistakes to avoid. Pulled straight from the Kovo app's exercise library.
- Equipment
- Bodyweight
- Difficulty
- Beginner
- Logged as
- Weighted reps
- Movement
- Flexion
- Mechanic
- Isolation
How to do it
Lie on your back with your legs extended straight along the floor and your hands behind your head or across your chest. Curl your shoulders and upper back off the floor by contracting your abs, then lower under control. Keep your legs straight and your chin off your chest.
- 1Feel your upper abs squeeze to curl your shoulders up
- 2Keep the movement slow and controlled at the top
- 3Press your lower back gently into the floor as you crunch
Common mistakes
- Do not pull on your neck with your hands
- Avoid yanking up with momentum or jerking off the floor
- Do not let your legs lift or bend to swing you up
Muscles worked
The straight legs lying crunch mainly works the upper abs, with the lower abs, obliques, and hip flexors assisting.
- Upper AbsPrimary
- Lower AbsSupport
- ObliquesSupport
- Hip FlexorsSupport
Kovo programs the straight legs lying crunch for you and tracks it every session.
We build your whole program, drop the right lifts into each workout, and adjust your weights as you get stronger. Free on iOS and Android.
More abs & core exercises
- How to do the ab wheel rollout
- How to do the ankle tap plank
- How to do the ankle taps
- How to do the resistance band dead bugs
- How to do the resistance band pallof press
- How to do the rollout
Last reviewed June 2026.