Seated Floor Crunch — how to, muscles worked, alternatives

How to do the Seated Floor Crunch

Sit with knees bent, heels on the floor, hands behind your head.
Lean back slightly, keeping your back straight and stomach tight.
Curl your torso forward, bringing your head toward your knees.
Slowly return to the leaned-back position, keeping your legs still.

Full technique — 6 steps

Sit on the floor with your knees bent and your heels on the floor in front of you.
Place your hands behind your head with elbows wide, without pulling on your neck.
Lean your torso back slightly, keeping your back straight and your stomach tight.
Exhale and curl your torso forward, bringing your ribs toward your pelvis.
Bring your chin slightly toward your chest as your upper back rounds toward your knees.
Return to the leaned-back position under control, keeping your legs still.

Common mistakes

Pulling the head with hands
Swinging the torso with momentum
Only moving at the hips
Lifting the feet off the floor
Dropping into the next rep

Form cues

Curl ribs toward pelvis
Exhale on the curl
Hands stay by head
Curl, don't yank up
Keep hips mostly still

Substitutes by equipment

Same muscles, same movement — pick the version you have the gear for.

Where to start and where to go next

Same muscles, same movement. Too hard for now — step down; once it gets easy — step up.

This exercise Seated Floor Crunch 15% of bodyweight
Harder Reverse Crunch 25% of bodyweight
Harder Ab Wheel Pass Crunch 30% of bodyweight

Quick answers

What muscles does the Seated Floor Crunch work?

Primary: Abs 9/10. Also works: Obliques 5/10, Lower back 3/10.

When should I do the Seated Floor Crunch in a workout?

Finisher. Goes last, once the heavy work is done. ≈ 5 min with rest.

How many sets and reps of the Seated Floor Crunch?

Strength: 3 sets of 10–15 reps, rest 1 min, 2 reps in reserve. Muscle growth: 3–4 sets of 12–20 reps, rest 1 min, 2–3 reps in reserve. Endurance: 2–3 sets of 20–30 reps, rest 40 s, 3–4 reps in reserve.

What can I do instead of the Seated Floor Crunch?

Barbell: Barbell Overhead Sit-Up. Resistance bands: Resistance Band Dead Bug, Lying Resistance Band Crunch. Weight plates: Plate Overhead Sit-Up. Suspension trainer: Suspension Trainer Mountain Climbers, Supine Suspension Trainer Knee Tuck.