Reverse Crunch Advanced with Straight Leg
Reverse crunch advanced with straight leg is a demanding bodyweight core exercise targeting the abs. Keeping the legs straight throughout the movement significantly increases the lever arm, intensifying the challenge on the lower abs and hip flexors.
How to do it
- Lie flat on your back with arms at your sides and legs straight, raised slightly off the floor.
- Without bending your knees, curl your hips off the floor and raise your straight legs toward the ceiling.
- Continue lifting until your legs are perpendicular to the floor or beyond.
- Hold briefly, then slowly lower your straight legs back to the starting position without touching the floor.
- Repeat for the desired number of repetitions.
Form cues
- Keep your legs completely straight throughout the entire movement.
- Press your lower back firmly into the floor before you begin.
- Use your lower abdominal muscles to lift your hips, not momentum.
- Lower your legs slowly and with control without touching the floor.
Breathing: Exhale as you lift your hips and legs toward the ceiling, and inhale slowly as you lower them back down.
Common mistakes
- Swinging your legs up using momentum, which takes the work away from your abs.
- Arching your lower back off the floor, which can cause strain and discomfort.
- Bending your knees to make the movement easier instead of choosing a regression.
Muscles worked
Primary: abs. Secondary: hip flexors, quads.
Suggested sets & reps
Get fitter
3 sets x 10-12 reps, rest 60 s
Lose weight
3 sets x 10-15 reps, rest 45 s
Build muscle
3 sets x 8-12 reps, rest 60 s
Easier, harder & alternatives
Make it easier
Make it harder
Take care if…
- If you feel lower back discomfort, ease off and choose a gentler regression.
- Stop immediately if you experience any sharp pain during the movement.
General educational guidance, not medical advice. Stop on sharp pain and check with a qualified professional if unsure.
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Start free →Frequently asked questions
Why do I feel this exercise in my hip flexors instead of my abs?
Keeping your legs straight significantly increases the load on your hip flexors. If it feels overwhelming, try a bent-knee regression to focus more on your abdominal muscles.
How can I stop my lower back from lifting off the floor?
Focus on pressing your lower back into the ground before starting each rep, and reduce your range of motion if your hips start to arch away from the floor.
How many times a week should I do this exercise?
You can safely include core exercises like this 2 to 3 times per week, allowing adequate rest days between sessions.